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Comparison of external morphological and movement patterns between Schistosoma japonicum and S. sinensis cercariae SONG Jing, ZHANG Zongya, SHEN Meifen, ZHOU Jihua, LI Chunying, YANG Zaogai, DONG Yi, DU Chunhong Chinese Journal of Schistosomiasis Control    2024, 36 (4): 384-387.   Abstract （474）      PDF（pc） （1203KB）（361）       Knowledge map    Save Objective　To compare the external morphological characteristics and movement patterns between Schistosoma japonicum and S. sinensis cercariae. Methods　S. japonicum and S. sinensis cercariae were heat⁃fixed, and well⁃extended cercariae, of 50 each species, were randomly selected for measurement of body length, body width, tail stem length, and tail fork length. The external morphological characteristics of S. japonicum and S. sinensis cercariae were compared. In addition, S. japonicum⁃infected Oncomelania snails and S. sinensis⁃infected Tricula snails were observed under a microscope and the movement patterns of S. japonicum and S. sinensis cercariae were compared. Results　The mean body length, body width, tail stem length, and tail fork length were (0.16 ± 0.01), (0.05 ± 0.01), (0.14 ± 0.01) mm and (0.06 ± 0.01) mm for S. japonicum cercariae, and (0.13 ± 0.01), (0.05 ± 0.01), (0.13 ± 0.01) mm and (0.06 ± 0.01) mm for S. sinensis cercariae, respectively, and there were significant differences in terms of cercaria body length (t = 14.583, P < 0.05) and tail stem length (t = 3.861, P < 0.05), while no significant differences were seen in terms of body width (t = 0.896, P > 0.05) or tail fork length (t = -0.454, P > 0.05). Microscopy revealed that the tails of both S. japonicum and S. sinensis cercariae swung from side to side and there was no significant difference in their movement pattern. Conclusion　S. sinensis and S. japonicum cercariae share highly similar external external morphological characteristics and movement patterns. Related Articles | Metrics | Comments（0）

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Analysis and forecast of the disease burden of schistosomiasis in China from 1992 to 2030 LIN Kai, ZHANG Chenhuan, XU Zhendong, LI Xuemei, HUANG Renzhan, LIU Yawen, YU Haihang, GU Lisi Chinese Journal of Schistosomiasis Control    2025, 37 (1): 24-34.   Abstract （404）      PDF（pc） （2297KB）（446）       Knowledge map    Save Objective　To analyze the trends in the disease burden of schistosomiasis in China from 1992 to 2021, and to project the disease burden of schistosomiasis in China from 2022 to 2030, so as to provide insights into the elimination of schistosomiasis in China.  Methods　The prevalence, age⁃standardized prevalence, disability⁃adjusted life year (DALYs) rate and age⁃standardized DALYs rate of schistosomiasis, as well as the years lost due to disability (YLDs) rate and age⁃standardized YLDs rate of anemia attributable to Schistosoma infections in China, the world and different socio⁃demographic index (SDI) regions were captured from the Global Burden of Disease Study 2021 (GBD 2021) data resources, and the trends in the disease burden due to schistosomiasis were evaluated with estimated annual percentage change (EAPC) and its 95% confidence interval (CI). In addition, the age, period and cohort effects on the prevalence of schistosomiasis were examined in China using an age⁃period⁃cohort (APC) model, and the disease burden of schistosomiasis was predicted in China from 2022 to 2030 using a Bayesian age⁃period⁃cohort (BAPC) model.  Results　The age⁃standardized prevalence and DALYs rate of schistosomiasis, and the age⁃standardized YLDs rate of anemia attributable to Schistosoma infections were 761.32/105, 5.55/105 and 0.38/105 in China in 2021. These rates were all lower than the global levels (1 914.30/105, 21.90/105 and 3.36/105, respectively), as well as those in the medium SDI regions (1 413.61/105, 12.10/105 and 1.93/105, respectively), low⁃medium SDI regions (2 461.03/105, 26.81/105 and 4.48/105, respectively), and low SDI regions (5 832.77/105, 94.48/105 and 10.65/105, respectively), but higher than those in the high SDI regions (59.47/105, 0.49/105 and 0.05/105, respectively) and high⁃medium SDI regions (123.11/105, 1.20/105 and 0.12/105, respectively). The prevalence and DALYs rate of schistosomiasis were higher among men (820.79/105 and 5.86/105, respectively) than among women (697.96/105 and 5.23/105, respectively) in China in 2021, while the YLDs rate of anemia attributable to Schistosoma infections was higher among women (0.66/105) than among men (0.12/105). The prevalence of schistosomiasis peaked at ages of 30 to 34 years among both men and women, while the DALYs rate of schistosomiasis peaked among men at ages of 15 to 19 years and among women at ages of 20 to 24 years. The age⁃standardized prevalence of schistosomiasis showed a moderate decline in China from 1992 to 2021 relative to different SDI regions [EAPC = -1.51%, 95% CI: (-1.65%, -1.38%)], while the age⁃standardized DALYs rate [EAPC = -3.61%, 95% CI: (-3.90%, -3.33%)] and age⁃standardized YLDs rate of anemia attributable to Schistosoma infections [EAPC = -4.16%, 95% CI: (-4.38%, -3.94%)] appeared the fastest decline in China from1992 to 2021 relative to different SDI regions. APC modeling showed age, period, and cohort effects on the trends in the prevalence of schistosomiasis in China from 1992 to 2021, and the prevalence of schistosomiasis appeared a rise followed by decline with age, and reduced with period and cohort. BAPC modeling revealed that the age⁃standardized prevalence and age⁃standardized DALYs rate of schistosomiasis, and age⁃standardized YLDs rate of anemia attributable to Schistosoma infections all appeared a tendency towards a decline in China from 2022 to 2030, which reduced to 722.72/105 [95% CI: (538.74/105, 906.68/105)], 5.19/105 [95% CI: (3.54/105, 6.84/105)] and 0.30/105 [95% CI: (0.21/105, 0.39/105)] in 2030, respectively. Conclusions　The disease burden of schistosomiasis appeared a tendency towards a decline in China from 1992 to 2021, and is projected to appear a tendency towards a decline from 2022 to 2030. There are age, period and cohort effects on the prevalence of schistosomiasis in China. Precision schistosomiasis control is required with adaptations to current prevalence and elimination needs.   Related Articles | Metrics | Comments（0）

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Application of artificial intelligence in parasitic diseases and parasitology ZHOU Yibiao Chinese Journal of Schistosomiasis Control    2024, 36 (6): 551-554.   Abstract （391）      PDF（pc） （4619KB）（338）       Knowledge map    Save The rapid development of artificial intelligence poses a huge impact on health and has become a core driving force for the new generation of the scientific and technological revolution in the field of healthcare. Recently, artificial intelligence has been gradually applied in the field of parasitic diseases and parasitology, including disease diagnosis, prognosis prediction, prediction of transmission risk, intelligent identification of vectors and intermediate hosts, and disease prevention and control, which facilitates the progress towards elimination of parasitic diseases. In addition, artificial intelligence provides highly efficient tools and approaches for healthcare workers and researchers. This comment mainly reviews the application of artificial intelligence in the fields of parasitic diseases and parasitology. Related Articles | Metrics | Comments（0）

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Establishment and application of an artificial intelligence⁃assisted platform for detection of parasite eggs ZHU Huiyin, LI Yuting, ZHU Daiqian, WANG Yaqian, ZHANG Jinhong, CHEN Shaoxuan, MA Xiaoyuan, WANG Huidi, LI Hongjun, LI Jian Chinese Journal of Schistosomiasis Control    2024, 36 (6): 643-648.   Abstract （364）      PDF（pc） （5473KB）（188）       Knowledge map    Save Objective　To establish an artificial intelligence (AI)⁃assisted platform for detection of parasite eggs, and to evaluate its detection efficiency and accuracy, so as to provide technical supports for elimination of parasitic diseases.  Methods　A total of 1 003 slides of Enterobius vermicularis, horkworm, Trichuris trichiura, Clonorchis sinensis, Taenia, Ascaris lumbricoides, Schistosoma japonicum, Paragonimus westermani and Fasciolopsis buski eggs were collected, and converted into digital images with an automatated scanning microscope to create a dataset. Based on the Object Detection platform on the Baidu Easy DL model, an AI⁃assisted platform for detection of parasite eggs was created through procedures of uploading, labeling, training, evaluation and optimization. Then, 70% of the datasets were randomly selected for model training, and the precision, recall and average accuracy were calculated to evaluate the effectiveness of platform for recognition of parasite eggs. In addition, the platform was deployed on the computer and smart phone terminals for use. Results　An AI⁃assisted platform for detection of parasite eggs was successfully created. If the platform was deployed using the public cloud application programming interface (API), the average accuracy, precision and recall of the platform were 93.42%, 92.55% and 89.32% for recognition of parasite eggs. If the platform was deployed using the offline software development kit (SDK), the average accuracy, precision and recall of the platform were 92.97%, 94.78% and 87.63% for recognition of parasite eggs. In addition, the precision of the platform was 97.00% and 96.23% for identification of Taenia and C. sinensis eggs, respectively. Conclusions　The AI⁃assisted platform for detection of parasite eggs has been successfully created, which is high in the accuracy for recognition of parasite eggs and convenient in use. This platform may provide a powerful technical support for parasitic disease diagnosis.  Related Articles | Metrics | Comments（0）

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Progress of researches on toxoplasmosis vaccines based on the CRISPR/Cas9 technology WU Yan, ZHANG Xin, LI Jin, XIE Jinjing, WANG Longjiang, SUN Hui Chinese Journal of Schistosomiasis Control    2024, 36 (5): 542-547.   Abstract （333）      PDF（pc） （953KB）（230）       Knowledge map    Save Toxoplasma gondii is an obligatory intracellular parasite which infects a variety of warm⁃blooded animals and causes toxoplasmosis. Toxoplasmosis seriously endangers human health and animal husbandry production. As one of the effective gene editing tools, the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR⁃associated proteins (Cas) system has been widely used for knockout of genes in T. gondii. This review summarizes the applications of the CRISPR/Cas9 technology in vaccines against single⁃ and double⁃gene deletion strains of T. gondii, so as to provide insights into development of toxoplasmosis vaccines. Related Articles | Metrics | Comments（0）

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Current status and challenges of zoonosis prevention and control: a One Health perspective LI Cihuai, CHEN Feng, LÜ Shan Chinese Journal of Schistosomiasis Control    2025, 37 (1): 98-103.   Abstract （322）      PDF（pc） （1059KB）（1198）       Knowledge map    Save Zoonosis prevention and control is a complex public health concern, which requires the collaboration of multiple regions, disciplines, and departments to enhance the effectiveness. The One Health concept aims to achieve the joint health security of humans, animals and environments through cross⁃disciplinary, cross⁃sector and cross⁃field collaborations. This review summarizes the development of One Health and the successful practices in the prevention and control of echinococcosis, rabies, COVID⁃19 and schistosomiasis, as well as explores the challenges faced in applying this concept to the prevention and control of zoonoses, so as to provide insights into formulation of the integrated zoonoses control strategy and implementation of zoonoses control interventions at the human⁃animal⁃environment interface. Related Articles | Metrics | Comments（0）

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Molluscicidal effect of spraying different formulations of niclosamide ethanolamine salt with drones against Oncomelania hupensis in ditches ZHU Zelin, ZHANG Xia, HE Junyi, CHEN Ying, WANG Weisi, HU Hehua, CAO Chunli, BAO Ziping, GUO Suying, DUAN Liping, YUAN Yi, XU Jing, LI Shizhu, ZHOU Xiaonong Chinese Journal of Schistosomiasis Control    2024, 36 (5): 527-530,541.   Abstract （312）      PDF（pc） （978KB）（239）       Knowledge map    Save Objective　To evaluate the molluscicidal effect of spraying different formulations of niclosamide ethanolamine salt with drones against Oncomelania hupensis in ditches. Methods　A semi⁃dry and semi⁃wet ditch with O. hupensis snails was selected in the second branch field of Jiangbei Farm, Jiangling County, Hubei Province in May 2023, and divided into 4 experimental areas, named groups A1, A2, B1 and B2. Environmental cleaning was performed in groups A1 and B2, and was not conducted in groups A2 or B2. Then, 50% wettable powder of niclosamide ethanolamine salt was sprayed with drones at a dose of 2 g/m2 in groups A1 and A2, and 5% niclosamide ethanolamine salt granule was sprayed with drones at an effective dose of 2 g/m2 in groups B1 and B2. O. hupensis snails were surveyed using the systematic sampling method 1, 3, 5, 7, 14 days after spraying, and the natural mortality and corrected mortality of O. hupensis snails were calculated. Results　The occurrence of frames with living snails, mean density of living snails and natural mortality of snails were 97.50% (117/120), 6.30 snails/0.1 m2 and 1.18% (9/765) in the test ditch before spraying, respectively. There were significant differences in the mortality of snails among four groups 1, 3, 5, 7 and 14 days after spraying niclosamide formulations with drones ([χ2] = 17.230, 51.707, 65.184, 204.050 and 34.435, all P values < 0.01). The overall mortality rates of snails were 94.51% (1 051/1 112), 79.44% (908/1 143), 96.54% (977/1 012) and 88.55% (1 021/1 153) in groups A1, A2, B1 and B2 ([χ2] = 207.773, P < 0.05), respectively. In addition, there was no significant difference in the overall snail mortality between groups A1 and B1 (P > 0.05), and the snail mortality in groups A1 and B1 were both statistically different from that in groups A2 and B2 (all P values < 0.05). Conclusion　Both 50% wettlable powder of niclosamide ethanolamine salt and 5% niclosamide ethanolamine salt granule sprayed with drones are active against O. hupensis snails in ditches, and environmental cleaning may improve the molluscicidal effect.  Related Articles | Metrics | Comments（0）

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Molluscicidal effect and costs of spraying pyriclobenzuron with drones against Pomacea canaliculata ZHAO Xiaolin, CHEN Ying, HU Yanyue, XU Yanggeng, WANG Youqi, LÜ Dan, WAN Chuanxu, SUN Yang, DUAN Liping, WANG Weisi, HUANG Shuijin Chinese Journal of Schistosomiasis Control    2024, 36 (5): 441-449.   Abstract （308）      PDF（pc） （2459KB）（419）       Knowledge map    Save Objective　To evaluate the molluscicidal effects and costs of spraying 20% suspension concentrate of pyriclobenzuron sulphate (SCPS) with drones against Pomacea canaliculata in paddy environments, so as to provide insights into the extensive applications of pyriclobenzuron against P. canaliculata. Methods　On July 2022, a paddy field was selected from Nanchang City, Jiangxi Province as the study area, and 72 independent rectangular plots measuring 2 m × 1 m were allocated in the study area, with 1 m interval between each plot, and 20 P. canaliculata snails gently placed in each plot. The activity of 25% wettable powder of pyriclobenzuron sulphate (WPPS) by manual spraying at doses of 0.50, 1.00, 2.00 g/m2 and 4.00 g/m2 against P. canaliculata was tested in 54 plots, and manual spraying of 50% wettable powder of niclosamide ethanolamine salt (WPNES) at a dose of 0.10 g/m2 served as a chemical control, while manual spraying of the same volume of clean water served as a blank control, with 9 plots in each group. The activity of SCPS against P. canaliculata was tested in the remaining 18 plots. Based on the molluscicidal tests of WPPS, the molluscicidal effect of SCPS by manual spraying at doses of 0.20, 0.30, 0.40 g/m2 and 0.50 g/m2 against P. canaliculata was evaluated, and manual spraying of WPNES at a dose of 0.10 g/m2 served as a chemical control, while manual spraying of the same volume of clean water served as a blank control, with three plots in each group. On July 2023, 14 paddy fields with a mean living P. canaliculata density of > 5 snails/m2 were selected from Yujiang District, Yingtan City, Jiangxi Province for molluscicidal tests. Based on the molluscicidal effect of pyriclobenzuron against P. canaliculata in plots, the molluscicidal effects of WPPS by manual spraying at doses of 0.25, 0.50 g/m2 and 1.00 g/m2 and manual applications of WPPS at dose of 0.25, 0.50, 1.00 g/m2 and 2.00 g/m2 mixed with soil were tested, and manual spraying of 0.10 g/m2 WPNES served as a chemical control group, while manual spraying of the same volume of clean water served as a blank control, with one paddy field in each group. Based on the effect of pyriclobenzuron against P. canaliculata in plots, the activity of SCPS sprayed with drones at doses of 0.25 g/m2 and 0.50 g/m2 mixed in water at 2 kg/667 m2 and 4 kg/667 m2 was tested against P. canaliculata, and spraying of the same volume of clean water with drones served as a blank control. All P. canaliculata snails were captured 3 days and 7 days following chemical treatment in plots and paddy fields and identified for survival, and the mortality and corrected mortality of P. canaliculata snails were estimated. In addition, the areas of chemical treatment, amount of molluscicide use and labor costs of chemical treatment were estimated in molluscicidal tests in paddy fields, and the costs of chemical treatment for an area covering 667 m2 by drones and manual applications were calculated. Results　The mortality of P. canaliculata snails was all 100% in plots 3 days and 7 days following spraying WPPS at doses of 0.50, 1.00, 2.00 g/m2 and 4.00 g/m2, and the mortality rates of P. canaliculata snails were 66.67% to 100.00% 3 days post⁃treatment with SCPS at various doses ([χ2] = 277.897, P < 0.05) and 76.67% to 100.00% 7 days post⁃treatment ([χ2] = 274.206, P < 0.05). The mortality rates of P. canaliculata snails were 98.19% to 100.00% 3 days post⁃treatment with WPPS at various doses in paddy fields. There was a significant difference in the mortality of P. canaliculata snails among WPPS treatment groups and controls ([χ2] = 270.778, P < 0.05), and there were no significant differences between WPPS treatment groups and the chemical control group (all P values > 0.05), while there were significant differences in the mortality of P. canaliculata snails between WPPS treatment groups and the blank control group (all P values < 0.05). The mortality rates of P. canaliculata snails were 89.83% to 95.31% 3 days post⁃treatment with SCPS at various doses sprayed with drones, and there was a significant difference in the mortality of P. canaliculata snails among SCPS treatment groups and the blank control group ([χ2] = 1 132.892, P < 0.05). There were no significant differences in the mortality of P. canaliculata snails among SCPS treatment groups or water mixture groups (all P values > 0.05), and there were significant differences in the mortality of P. canaliculata snails between SCPS treatment groups and the blank control group (all P values < 0.05). The mortality rates of P. canaliculata snails were 94.62% to 100.00% 7 days post⁃treatment with SCPS at various doses sprayed with drones, and there was a significant difference in the mortality of P. canaliculata snails among SCPS treatment groups and the blank control group ([χ2] = 1 266.932, P < 0.05), with the highest mortality found following spraying 0.50 g/m2 SCPS mixed in 2 kg/667 m2 water with drones (P < 0.05). The costs of P. canaliculata snail control by drones and manually were 35.85 Yuan/667 m2 and 43.33 Yuan/667 m2; however, the snail control efficiency was 6.67 times higher by drones than by manual applications. Conclusions　SCPS sprayed with drones is highly active against P. canaliculata snails in paddy fields. SCPS sprayed with drones is highly efficient and low in cost for P. canaliculata snail control in paddy fields, beaches and river courses. Related Articles | Metrics | Comments（0）

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Optimization of the control strategy and research priorities to combat the resurgence of visceral leishmaniasis in China ZHOU Xiaonong, LI Shizhu, CHEN Junhu, ZHANG Yi Chinese Journal of Schistosomiasis Control    2024, 36 (4): 329-333.   Abstract （299）      PDF（pc） （516KB）（411）       Knowledge map    Save Leishmaniasis is a zoonotic parasitic disease caused by Leishmania infection and transmitted by sandflies. There are three main forms of leishmaniasis, including cutaneous leishmaniasis, visceral leishmaniasis and mucocutaneous leishmaniasis. China is mainly endemic for visceral leishmaniasis, which is a class C notifiable infectious disease in the country. Following concerted efforts, the transmission of visceral leishmaniasis had been controlled in most endemic foci of China by the end of 1958, with a few cases reported in western China. Due to global climate changes and population mobility, resurgence of visceral leishmaniasis has recently occurred in historical endemic areas of central and western China, which is characterized by gradual expansion of endemic areas and remarkable rebounding epidemics. Hereby, we summarize the national and global epidemiology and control strategy of visceral leishmaniasis, propose 8 key research areas and 12 key research topics for visceral leishmaniasis control, and recommend the establishment of the joint prevention and control mechanism of "human⁃animals⁃vectors" and the working mechanism of animal prevention for human diseases based on the One Health approach, so as to combat the resurgence of visceral leishmaniasis in China. Related Articles | Metrics | Comments（0）

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Advances in detection methods for fish⁃borne parasites in aquatic products ZHANG Yaoguang, WANG Zhenyu, CHEN Jian, YU Qing Chinese Journal of Schistosomiasis Control    2024, 36 (4): 428-434,438.   Abstract （292）      PDF（pc） （1021KB）（1351）       Knowledge map    Save Consumption of raw and semi⁃raw aquatic products is strongly associated with the development of fish⁃borne parasitic diseases. Detection of fish⁃borne parasites in aquatic products is of great significance for the prevention and control of fish⁃borne parasitic diseases. This review describes the advances in the application of etiological, molecular biological and immunological techniques alone and in combinations for detection of fish⁃borne parasites, so as to provide insights into detection of fish⁃borne parasites. Related Articles | Metrics | Comments（0）

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Application of drones in Oncomelania hupensis snail control with molluscicides HUANG Yixin Chinese Journal of Schistosomiasis Control    2024, 36 (5): 439-440,449.   Abstract （287）      PDF（pc） （1007KB）（522）       Knowledge map    Save Oncomelania hupensis snail control by chemical treatment is an important approach for control and elimination of snails, and an appropriate apparatus for spraying chemicals is an important support to molluscicidal effects. Nevertheless, the research and evaluation of molluscicidal apparatuses have not been paid high attention in the schistosomiasis control programme for a long period of time. Currently, agricultural plant⁃protective apparatuses have been widely used for chemical treatment. This comment provides a short overview of the application of drones in O. hupensis snail control by chemical treatment, and proposes suggestions for solving the problems of use of drones in O. hupensis snail control by chemical treatment in China. Related Articles | Metrics | Comments（0）

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First overseas imported case of schistosomiasis haematobia in Xihu District, Hangzhou City   ZHANG Huami, SU Xing, ZHANG Jianfeng, ZHANG Yingyi Chinese Journal of Schistosomiasis Control    2024, 36 (5): 548-550.   Abstract （282）      PDF（pc） （1055KB）（238）       Knowledge map    Save This paper reports the diagnosis and treatment of the first imported case of schistosomiasis haematobia in Xihu District of Hangzhou. The patient was an international student from Zimbabwe, and experienced repeated gross hematuria without obvious motivation. Cystoscopy displayed bladder masses, and a large number of fresh or calcified parasite eggs were found in pathological sections. In addition, urine microscopy identified Schistosoma haematobium eggs. The case was therefore definitively diagnosed as overseas imported case of imported schistosomiasis haematobia. Another case of schistosomiasis mansoni was identified among international students in the same school with the patient above by indirect haemagglutination test and urine and stool etiology examination. It is recommended to intensify health education and monitoring among overseas floating populations and improve the diagnostic skills of overseas imported schistosomiasis among professionals working in medical and disease control and prevention institutions, in order to prevent misdiagnosis and mistreatment.  Related Articles | Metrics | Comments（0）

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Risk factors of visceral leishmaniasis in the world: a review CHEN Xi, SHI Yue, ZHOU Sheng, GENG Mengjie, TU Hong, SONG Jiandong, ZHENG Canjun, SUN Junling Chinese Journal of Schistosomiasis Control    2024, 36 (4): 412-421,427.   Abstract （262）      PDF（pc） （1023KB）（1661）       Knowledge map    Save Visceral leishmaniasis is a zoonotic parasitic disease caused by viscerotropic Leishmania species and transmitted by bites of infected phlebotomine sandflies, which is predominantly prevalent in the Indian subcontinent, eastern Africa and South America. Currently, visceral leishmaniasis is the second most fatal parasitic disease in the world. Because of climate changes, urban development and individual conditions, there are changes in the density of visceral leishmaniasis vector sandflies and the likelihood of contact with humans, resulting in a visceral leishmaniasis transmission risk. The review summarizes natural, social and biological factors affecting the transmission of visceral leishmaniasis, so as to provide insights into formulation of targeted control measures for visceral leishmaniasis. Related Articles | Metrics | Comments（0）

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Cost⁃effectiveness analysis of chemical treatment with drones for snail control in marshland and lake areas CHEN Yong, XU Xiaojuan, WEN Daolong, DAI Bo, GAO Lan, ZHANG Rong, HUANG Qingqing, LI Linlin, ZHA Fan, FANG Liang, ZHANG Ping, ZHANG Shiqing, CAO Chunli Chinese Journal of Schistosomiasis Control    2024, 36 (5): 502-506.   Abstract （257）      PDF（pc） （984KB）（173）       Knowledge map    Save Objective　To evaluate the molluscicidal effect and cost of spraying molluscicides with drones against Oncomelania hupensis snails in marshland and lake areas, so as to provide new insights into field snail control in China. Methods　A marshland and lake setting measuring approximately 12 000 m2 was selected in Wanzhi District, Wuhu City on June 2023 as the test field, and assigned to four groups, of 3 000 m2 in each group. Environmental cleaning was not conducted in groups A or B, which were given 5% niclosamide ethanolamine salt granules sprayed with knapsack⁃type sprayers and drones at a dose of 40 g/m2, and environmental cleaning was conducted in groups C and D, which were given 5% niclosamide ethanolamine salt granules sprayed with drones and knapsack⁃type sprayers at a dose of 40 g/m2, respectively. O. hupensis snails were surveyed before chemical treatment and 1, 3, 5, 7, 14 days post⁃treatment. The uniformity of chemicals was determined on the day of treatment, and the snail mortality, corrected snail mortality and density of living snails were calculated and compared among groups. The cost of molluscicides, labor fees of environmental cleaning and chemical treatment and cost of equipment were calculated, and the cost for a 1% reduction in the mean density of living snails was calculated 14 days post⁃treatment. Results　The mean densities of living snails and mortality rates of snails were 1.82 to 2.85 snails/0.1 m2 and 1.41% to 2.94% in groups A, B, C and D before chemical treatment, and the mortality and corrected mortality of snails were 55.75%, 49.32%, 85.94% and 87.50%, and 55.00%, 48.47%, 85.70% and 87.29% in groups A, B, C and D 14 days post⁃treatment. There was a significant difference in the mortality of snails among the four groups 14 days post⁃treatment ([χ2]  = 38.735, P < 0.005), and there was a higher snail mortality in Group D than in Group A ([χ2]  = 16.876, P < 0.005), and higher in Group C than in Group B ([χ2]  = 20.508, P < 0.005). The density of living snails reduced by 55.00%, 43.94%, 90.43% and 87.14% 14 days post⁃treatment relative to pre⁃treatment in groups A, B, C and D, respectively. The test for uniformity of chemicals showed that the mean dose of molluscicides were 57.34, 55.21, 40.19 g/m2 and 32.37 g/m2 in groups A, B, C and D, respectively, and the minimal standard deviation (7.07) and coefficient of variation (0.18) of mean doses were seen in Group C. The costs for chemical treatment were 0.33 Yuan in groups A and B and 1.53 Yuan in groups C and D, respectively. The costs for a 1% reduction in the mean density of living snails were 17.82, 22.47, 50.73 Yuan and 52.56 Yuan in groups A, B, C, and D 14 days post⁃treatment, respectively.  Conclusions　The molluscicidal effect and cost of spraying 5% niclosamide ethanolamine salt granules with drones are comparable to manual spraying, and chemical treatment with drones are high in uniformity of molluscicides, time⁃ and labor⁃saving, and feasible for applications in complex environments, which deserves widespread applications in the field of snail control. Related Articles | Metrics | Comments（0）

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Malaria elimination strategy and joint prevention and control of malaria across China⁃Myanmar border areas: an overview WEI Chun, LIN Zurui, YANG Zhonghua, ZHOU Hongning, ZHOU Xingwu, YANG Rui Chinese Journal of Schistosomiasis Control    2025, 37 (1): 19-23,54.   Abstract （252）      PDF（pc） （1100KB）（359）       Knowledge map    Save Yunnan Province borders with Myanmar, Vietnam, and Laos, the China⁃Myanmar border area is the key area for prevention of re⁃establishment from imported malaria after the disease was eliminated in China. Since the malaria elimination action plan was launched in Yunnan Province in 2011, 129 counties (cities, districts) were classified into three categories according to malaria incidence and transmission risk, and different technical strategies and measures were implemented with adaptations to local circumstances. A total of 68 malaria consultation service stations were established on the Chinese side of the China⁃Myanmar border and 80 malaria prevention and control stations were established on the Myanmar side by Yunnan Province in 2014. Then, the ''Three Lines of Defense'' strategy was implemented for malaria elimination in the China⁃Myanmar border area in Yunnan Province during the period from 2015 to 2018, and this strategy was further refined and adjusted to the ''3 + 1'' strategy for prevention of re⁃establishment from imported malaria in 2019. Through decades of multifaceted efforts, the malaria elimination goal was achieved in Yunnan Province in June 2021. However, the number of imported malaria cases appeared a tendency towards a rise in Yunnan Province in 2023 and 2024, due to changes in the situation in Myanmar and the gradual resumption of international travel and border crossings following the adjustment of the COVID⁃19 prevention and control policy in China. The joint malaria prevention and control cooperation between China and Myanmar was initiated with the pilot project for joint malaria prevention and control in the China⁃Myanmar border area in 2005, and this project was progressed into the joint malaria and dengue fever prevention and control project in parts of the Greater Mekong Subregion border areas in 2010. The threat of overseas malaria epidemics to border areas in Yunnan Province was effectively reduced through implementation of coordination meetings with Myanmar health departments, establishment of efficient information exchange mechanisms, establishment of overseas surveillance sentinel sites, technical training, provision of material supports, joint propagation activities and joint responses to malaria epidemics. This project was incorporated into the Five⁃Year Plan of Action on Lancang⁃Mekong Cooperation (2018—2022) in China in 2018, with 5 liaison offices and 20 liaison workstations established in Myanmar, Laos, Vietnam, Cambodia, and Thailand, and 21 cross⁃border malaria surveillance sites assigned in border areas of Myanmar, Laos and Vietnam, and a long⁃term malaria prevention and control cooperation mechanisms was established through meetings, training, propagation, and joint investigations. Currently, Yunnan Province is poised to engage in more extensive and in⁃depth cooperation with neighboring countries, including malaria diagnosis and treatment techniques, drug and vaccine research and development, talent cultivation, information sharing, cross⁃border human health services, and health promotion, under the guidance of the Five⁃Year Plan of Action on Lancang⁃Mekong Cooperation (2023—2027). Related Articles | Metrics | Comments（0）

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Surveillance of the population density of adult Aedes albopictus in Guangdong Province from 2018 to 2023 LU Ruipeng, CHENG Mingji, LUO Ao, CHEN Yating, LUO Min, DUAN Jinhua, CHEN Zongjing, ZHONG Yuwen, HU Shengjun, DENG Hui Chinese Journal of Schistosomiasis Control    2024, 36 (6): 591-597.   Abstract （250）      PDF（pc） （7274KB）（155）       Knowledge map    Save Objective　To investigate the fluctuations in the population density of Aedes albopictus and changes in the population density of Ae. albopictus in different geographical areas and different breeding habitats in Guangdong Province from 2018 to 2023, so as to provide insights into prevention and control of mosquito⁃borne infectious diseases in the province. Methods　Ae. albopictus surveillance sites were assigned in 1 609 townships (streets) from 121 districts (counties) of 21 cities in Guangdong Province during the period between March and November from 2018 to 2023. The surveillance of the population density of Ae. albopictus was performed once a month in each surveillance site, and once a month in specific settings in cities where dengue were highly prevalent in Guangdong Province from December to February of the next year during the period from 2018 through 2023. Four streets (villages) were selected in each surveillance site according to the geographic orientation, and mosquito ovitraps were assigned in gardens, rooftops or public green belts at residential areas, parks, hospitals and construction sites. All mosquito ovitraps were collected, and the mosquito ovitrap index (MOI) was calculated. The population density of Ae. albopictus was classified into four grades in each surveillance site according to MOI, including no risk, low risk, medium risk and high risk. The risk classification of the Ae. albopictus density was analyzed in each surveillance site each year from 2018 to 2023, and the population density of Ae. albopictus was analyzed at different months and in different geographical areas and breeding habitats.  Results　A total of 118 241 Ae. albopictus surveillance sites were assigned in 21 cities of Guangdong Province from 2018 to 2023, and there were 68.26% of the surveillance sites with the population density of Ae. albopictus that met the requirements for dengue prevention and control, among which low, medium and high risk surveillance sites accounted for 23.61%, 6.67% and 1.47%. The risk classification of the Ae. albopictus density increased rapidly in Guangdong Province since April to May each year from 2018 to 2023, and then gradually reduced since September to October, with the peak during the period between May and July. The mean MOI was 4.21 at each surveillance site in Guangdong Province during the period from 2018 to 2023, with 4.69, 4.80, 4.38, 3.82, 3.38, and 4.33 from 2018 to 2023, respectively. The MOI was 4.35, 4.43, 3.53 and 3.58 in the Pearl River Delta region, and eastern, western, and northern Guangdong Province, respectively, and was 4.18, 5.44, 4.75, 3.24, 4.27 and 3.70 in residential areas, parks, construction sites, hospitals, waste collection stations, and other breeding habitats, respectively. Conclusions　The population density of adult Ae. albopictus peaked in Guangdong Province during the period between May and July from 2018 to 2023, with a high density of Ae. albopictus in the Pearl River Delta region and eastern Guangdong Province. Targeted Ae. albopictus control measures are recommended to be implemented prior to the peak of the Ae. albopictus population density to reduce the development of mosquito⁃borne infectious diseases. Related Articles | Metrics | Comments（0）

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Trends in areas of Oncomelania hupensis snail habitats in Anhui Province from 2004 to 2023 based on the Mann⁃Kendall test GAO Fenghua, ZHANG Shiqing, DING Songjun, XU Xiaojuan, WANG Tianping, DAI Bo Chinese Journal of Schistosomiasis Control    2024, 36 (5): 460-465.   Abstract （249）      PDF（pc） （1527KB）（722）       Knowledge map    Save Objective　To investigate the trends in areas of Oncomelania hupensis snail habitats in Anhui Province from 2004 to 2023, so as to provide insights into facilitating the progress of schistosomiasis elimination in the province.  Methods　Areas of O. hupensis snail habitats in Anhui Province from 2004 to 2023 were collected, and the trends in and mutations of O. hupensis snail habitats in Anhui Province, and the trends in O. hupensis snail habitats in different types of schistosomiasis⁃endemic foci and in different cities of Anhui Province from 2004 to 2023 were analyzed using Mann⁃Kendall test. Results　The areas of O. hupensis snail habitats reduced by 12.62% in Anhui Province in 2023 relative to in 2004. Mann⁃Kendall trend test showed that the areas of O. hupensis snail habitats appeared a tendency towards a decline in Anhui Province from 2004 to 2023 (Z = -3.926, P < 0.001, β = -215.66), with an annual average reduction of 215.66 hm2. Mann⁃Kendall mutation test showed that the areas of O. hupensis snail habitats appeared a tendency towards a decline in Anhui Province since 2015 (|Z| > U0.05, P < 0.05). The areas of O. hupensis snail habitats appeared a tendency towards a decline in marshland and lake regions (Z = -4.899, P < 0.001, β = -260.13), and a tendency towards a rise in hilly regions of Anhui Province from 2004 to 2023 (Z = 2.758, P < 0.01, β = 44.55). Among 9 cities endemic for schistosomiasis in Anhui Province, the areas of O. hupensis snail habitats appeared a tendency towards a decline in 5 cities of Ma'anshan, Tongling, Anqing, Huangshan and Chizhou (Z = -4.056 to -2.109, all P values < 0.05, β = -92.12 to -0.45). The average constituent ratios of areas of O. hupensis snail habitats were 88.19% and 11.81% in marshland and lake regions and hilly regions of Anhui Province from 2004 to 2023, respectively, and the ratio of areas of O. hupensis snail habitats in marshland and lake regions to areas of snail habitats in hilly regions reduced from 9.23∶1 in 2004 to 5.74∶1 in 2023 in Anhui Province, with the ratio appearing a tendency towards a decline (Z = -4.477, P < 0.001, β = -0.16). Conclusions　The areas of O. hupensis snail habitats appeared a tendency towards a decline in Anhui Province from 2004 to 2023, with a reduction in areas of O. hupensis snail habitats in marshland and lake regions and a rise in hilly regions. Targeted O. hupensis snail control interventions are required tailored to real snail status.  Related Articles | Metrics | Comments（0）

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Nippostrongylus brasiliensis alleviates dextran sulfate sodium salt⁃induced ulcerative colitis in mice: a preliminary study  ZHANG Yingshu, YUAN Caiyi, WANG Qiang, DING Xin, YAO Jiakai, ZHANG Bei, QIAO Shumiao, DAI Yang Chinese Journal of Schistosomiasis Control    2024, 36 (5): 450-459,473.   Abstract （247）      PDF（pc） （3112KB）（464）       Knowledge map    Save Objective　To investigate the alleviation of Nippostrongylus brasiliensis infection on dextran sulfate sodium salt (DSS)⁃induced ulcerative colitis in mice, and to explore the underlying mechanism. Methods　Thirty male C57BL/6J mice of the SPF grade, each weighing approximately 25 g, were randomly divided into three groups, including the blank control group (NC group), DSS modeling group (DSS group), and N. brasiliensis treatment group (Nb + DSS group), of 10 mice in each group. Mice in the DSS group were orally administered with 3.5% DSS daily since day 1 (D0) for 6 successive days, and given normal drinking water since D6, and animals in the Nb + DSS group were subcutaneously injected with the third⁃stage larvae of N. brasiliensis at a dose of 500 larvae per mice 5 days prior to D0, followed by oral administration with 3.5% DSS daily since D0 for 6 successive days and normal drinking water since D6, while mice in the NC group were given normal drinking water. Mouse body weight and stool were observed and the disease activity index (DAI) was scored in each group during the study period. All mice were sacrificed on D9. The mouse colon length was measured, and mouse colon specimens were subjected to hematoxylin⁃eosin (HE) staining and histopathological scoring. In addition, the mRNA and protein expression of interleukin (IL)⁃1β and IL⁃10 was quantified in mouse colon specimens using quantitative fluorescent real⁃time PCR (qPCR) assay and enzyme⁃linked immunosorbent assay (ELISA), and the mRNA and protein expression of mucosal repair⁃associated molecules zonula occludens⁃1 (ZO⁃1), mucin 2 (MUC2) and claudin⁃1 was detected in mouse colon specimens using qPCR assay and immunofluorescence assay. Results　The mice body weights, DAI scores and colon lengths were (26.26 ± 1.93), (22.39 ± 1.65), (25.00 ± 1.58) g (F = 8.06, P < 0.01); (1.89 ± 0.34), (0.47 ± 0.39), 0 points (F = 57.61, P < 0.000 1); and (42.50 ± 5.75), (56.20 ± 5.96) mm and (61.17 ± 7.88) mm (F = 13.72, P < 0.001) in the NC, DSS and Nb + DSS groups on D9, respectively, and elevated mouse body weight (P < 0.05), reduced DAI score (P < 0.000 1) and increased colon length (P < 0.01) were observed in the Nb + DSS group relative to the DSS group on D9. Pathological examinations showed that the colonic crypts were relatively intact and the inflammatory cell infiltration was lower in the mouse colon specimens in the Nb + DSS group than in DSS the group. There was a significant difference in the histopathological scores of mouse colon specimens among the NC group (0 point), the DSS group [(2.00 ± 1.22) points] and the Nb + DSS group [(0.20 ± 0.45) points] (F = 10.71, P < 0.01), respectively, and the histopathological score of mouse colon specimens was significantly higher in the DSS group than in the NC and Nb + DSS groups (both P values < 0.01). qPCR assay quantified that the relative IL⁃10 and IL⁃1β mRNA expression was 1.25 ± 0.08, 0.44 ± 0.14 and 1.30 ± 0.45 (F = 10.66, P < 0.01), and 0.22 ± 0.13, 1.14 ± 0.31 and 0.41 ± 0.19 (F = 16.89, P < 0.001) in mouse colon specimens in the NC, DSS and Nb + DSS groups, respectively, and higher IL⁃10 mRNA expression and lower IL⁃1β mRNA expression were found in mouse colon specimens in the Nb + DSS group than in the DSS group (both P values < 0.01). The relative MUC2, claudin⁃1 and ZO⁃1 mRNA expression was 0.87 ± 0.25, 0.34 ± 0.26 and 4.21 ± 0.55 (F = 121.60, P < 0.000 1), 1.05 ± 0.41, 0.16 ± 0.09 and 0.22 ± 0.11 (F = 14.00, P < 0.01), and 1.03 ± 0.10, 0.60 ± 0.11 and 1.64 ± 0.28 (F = 32.16, P < 0.000 1) in mouse colon specimens in the NC, DSS and Nb + DSS groups, respectively, and significantly higher MUC2 and ZO⁃1 mRNA expression was quantified in mouse colon specimens in the Nb + DSS group than in the DSS group (both P values < 0.05). The mean fluorescence intensities of ZO⁃1 and claudin⁃1 were 17.18 ± 2.08, 12.38 ± 1.21 and 18.06 ± 2.59 (F = 8.95, P < 0.01) and 13.50 ± 1.63, 9.66 ± 2.03 and 13.61 ± 0.97 (F = 6.96, P < 0.05) in mouse colon specimens in the NC, DSS and Nb + DSS groups, respectively, and the mean fluorescence intensities of ZO⁃1 and claudin⁃1 were significantly greater in mouse colon specimens in the Nb + DSS group than in the DSS group (both P values < 0.05).  Conclusion　N. brasiliensis infection may remarkably alleviate DSS⁃induced ulcerative colitis in mice through promoting expression of anti⁃inflammatory cytokines, inhibiting expression of pro⁃inflammatory cytokines and facilitating mucosal repair in colon tissues. Related Articles | Metrics | Comments（0）

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Epidemiological and spatial distribution characteristics of Clonorchis sinensis human infections in Guangdong Province from 2016 to 2022 ZHANG Guanting, ZHANG Qiming, FANG Yueyi, PEI Fuquan, MAO Qiang, LIU Jiahui, DENG Zhuohui, WU De, LU Wencheng, LIU Jun, LIAO Yuhuang, ZHANG Jiayi, CHEN Jingdiao Chinese Journal of Schistosomiasis Control    2024, 36 (6): 584-590.   Abstract （246）      PDF（pc） （6803KB）（215）       Knowledge map    Save Objective　To investigate the epidemiological characteristics and spatial distribution characteristics of Clonorchis sinensis human infections in Guangdong Province from 2016 to 2022, so as to provide insights into formulation of the clonorchiasis control measures in the province.  Methods  Xinhui District of Jiangmen City, Longmen County of Huizhou City and Wengyuan County of Shaoguan City in Guangdong Province were selected as fixed surveillance sites for human clonorchiasis from 2016 to 2022, and additional 10% to 15% counties (districts) endemic for clonorchiasis were sampled from Guangdong Province as mobile surveillance sites each year from 2016 to 2022. A village (community) was randomly selected from each surveillance site according to the geographical orientations of east, west, south, north and middle, and subjects were randomly sampled from each village (community). C. sinensis eggs were detected in subjects' stool samples using the Kato⁃Katz technique, and the prevalence and intensity of C. sinensis infections were calculated. In addition, subjects' gender, age, ethnicity, educational level and occupation were collected. The Guangdong Provincial 1∶1 million electronic map in vector format was downloaded from the National Geomatics Center of China, and kernel density analysis and spatial autocorrelation analysis of C. sinensis human infections in Guangdong Province from 2016 to 2022 were performed using the software ArcGIS 10.7.  Results　A total of 153 188 residents were tested for C. sinensis infections in Guangdong Province from 2016 to 2022, including 75 596 men (49.35%) and 77 592 women (50.65%), and there were 5 369 residents infected with C. sinensis, with 3.50% overall prevalence of infections. The prevalence rates of severe, moderate and mild C. sinensis infections were 0.76%, 7.26% and 91.97% among C. sinensis⁃infected residents in Guangdong Province from 2016 to 2022, and there were age⁃, gender⁃, ethnicity⁃, occupation⁃ and educational level⁃specific prevalence of C. sinensis human infections ([χ2] = 2 578.31, 637.33, 52.22, 2 893.28 and 1 139.33, all P values < 0.05). Global spatial autocorrelation analysis showed a cluster in the prevalence of C. sinensis human infections in Guangdong Province (Moran's I = 0.63, Z = 27.31，P < 0.05). Kernel density analysis showed that the prevalence of C. sinensis human infections with a high kernel density in Guangdong Province was mainly distributed along the Zhujiang River basin in Pearl River Delta areas, followed by in eastern and northern Guangdong Province. In addition, local spatial autocorrelation analysis identified 73 high⁃high clusters of the prevalence of C. sinensis human infections in Guangdong Province. Conclusions　The prevalence of C. sinensis human infections was high in Guangdong Province from 2016 to 2022, and mild infection was predominant among all clonorchiasis cases, with spatial clusters identified in the prevalence of C. sinensis human infections. Targeted clonorchiasis control measures are required among high⁃risk populations and areas.  Related Articles | Metrics | Comments（0）

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Application of machine learning models in schistosomiasis control: a review ZHOU Yu, TONG Yixin, ZHOU Yibiao Chinese Journal of Schistosomiasis Control    2024, 36 (5): 535-541.   Abstract （245）      PDF（pc） （975KB）（360）       Knowledge map    Save Schistosomiasis is a major public health concern in the world, and precision control is crucial to combating this disease. Due to the complex and diverse transmission route of schistosomiasis, conventional statistical models have significant limitations for precision control of schistosomiasis. As an important branch of artificial intelligence, machine learning has shown remarkable advantages in schistosomiasis control and research. It has been shown that machine learning is highly effective for disease prediction and risk assessment, so as to optimize the disease control strategy and resource allocation and achieve the precision control target. This review summarizes the characteristics of machine learning models and their applications in the research of intermediate host snails and schistosomiasis. Related Articles | Metrics | Comments（0）

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Evaluation of the performance of the artificial intelligence⁃enabled snail identification system for recognition of Oncomelania hupensis robertsoni and Tricula ZHOU Jihua, BAI Shaowen, SHI Liang, ZHANG Jianfeng, DU Chunhong, SONG Jing, ZHANG Zongya, YAN Jiaqi, WU Andong, DONG Yi, YANG Kun Chinese Journal of Schistosomiasis Control    2025, 37 (1): 55-60,68.   Abstract （241）      PDF（pc） （2014KB）（278）       Knowledge map    Save Objective　To evaluate the performance of the artificial intelligence (AI)⁃enabled snail identification system for recognition of Oncomelania hupensis robertsoni and Tricula in schistosomiasis⁃endemic areas of Yunnan Province. Methods　Fifty O. hupensis robertsoni and 50 Tricula samples were collected from Yongbei Township, Yongsheng County, Lijiang City, a schistosomiasis⁃endemic area in Yunnan Province in May 2024. A total of 100 snail sample images were captured with smartphones, including front⁃view images of 25 O. hupensis robertsoni and 25 Tricula samples (upward shell opening) and back⁃view images of 25 O. hupensis robertsoni and 25 Tricula samples (downward shell opening). Snail samples were identified as O. hupensis robertsoni or Tricula by schistosomiasis control experts with a deputy senior professional title and above according to image quality and morphological characteristics. A standard dataset for snail image classification was created, and served as a gold standard for recognition of snail samples. A total of 100 snail sample images were recognized with the AI⁃enabled intelligent snail identification system based on a WeChat mini program in smartphones. Schistosomiasis control professionals were randomly sampled from stations of schistosomisis prevention and control and centers for disease control and prevention in 18 schistosomiasis⁃endemic counties (districts, cities) of Yunnan Province, for artificial identification of 100 snail sample images. All professionals are assigned to two groups according the median years of snail survey experiences, and the effect of years of snail survey experiences on O. hupensis robertsoni sample image recognition was evaluated. A receiver operating characteristic (ROC) curve was plotted, and the sensitivity, specificity, accuracy, Youden's index and the area under the curve (AUC) of the AI⁃enabled intelligent snail identification system and artificial identification were calculated for recognition of snail sample images. The snail sample image recognition results of AI⁃enabled intelligent snail identification system and artificial identification were compared with the gold standard, and the internal consistency of artificial identification results was evaluated with the Cronbach's coefficient alpha. Results　A total of 54 schistosomiasis control professionals were sampled for artificial identification of snail sample image recognition, with a response rate of 100% (54/54), and the accuracy, sensitivity, specificity, Youden's index, and AUC of artificial identification were 90%, 86%, 94%, 0.80 and 0.90 for recognition of snail sample images, respectively. The overall Cronbach's coefficient alpha of artificial identification was 0.768 for recognition of snail sample images, and the Cronbach's coefficient alpha was 0.916 for recognition of O. hupensis robertsoni snail sample images and 0.925 for recognition of Tricula snail sample images. The overall accuracy of artificial identification was 90% for recognition of snail sample images, and there was no significant difference in the accuracy of artificial identification for recognition of O. hupensis robertsoni (86%) and Tricula snail sample images (94%) ([χ2] = 1.778, P > 0.05). There was no significant difference in the accuracy of artificial identification for recognition of snail sample images with upward (88%) and downward shell openings (92%) ([χ2] = 0.444, P > 0.05), and there was a significant difference in the accuracy of artificial identification for recognition of snail sample images between schistosomiasis control professionals with snail survey experiences of 6 years and less (75%) and more than 6 years (90%) ([χ2] = 7.792, P < 0.05). The accuracy, sensitivity, specificity and AUC of the AI⁃enabled intelligent snail identification system were 88%, 100%, 76% and 0.88 for recognition of O. hupensis robertsoni snail sample images, and there was no significant difference in the accuracy of recognition of O. hupensis robertsoni snail sample images between the AI⁃enabled intelligent snail identification system and artificial identification ([χ2] = 0.204, P > 0.05). In addition, there was no significant difference in the accuracy of artificial identification for recognition of snail sample images with upward (90%) and downward shell openings (86%) ([χ2] = 0.379, P > 0.05), and there was a significant difference in the accuracy of artificial identification for recognition of snail sample images between schistosomiasis control professionals with snail survey experiences of 6 years and less and more than 6 years ([χ2] = 5.604, P < 0.025). Conclusions　The accuracy of recognition of snail sample images is comparable between the AI⁃enabled intelligent snail identification system and artificial identification by schistosomiasis control professionals, and the AI⁃enabled intelligent snail identification system is feasible for recognition of O. hupensis robertsoni and Tricula in Yunnan Province. Related Articles | Metrics | Comments（0）

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China's participation in schistosomiasis control in Africa: value and practice of the trinity model HE Jian, WANG Xinyao, HUANG Yuzheng, Saleh JUMA, Mayassa ALLY, ZHOU Xiaonong, YANG Kun Chinese Journal of Schistosomiasis Control    2025, 37 (1): 1-7,13.   Abstract （236）      PDF（pc） （1407KB）（462）       Knowledge map    Save As a neglected tropical disease, schistosomiasis remains a major public health challenge in underdeveloped areas, notably Africa. Currently, the national schistosomiasis control programmes in Africa mainly depend on foreign aids; however, conventional international aid models have multiple limitations. To enhance the effectiveness and sustainability of global schistosomiasis control programmes, this article proposes a trinity collaboration model based on international rules, China's experiences and local needs, which is explained with China aid project of schistosomiasis control in Zanzibar as an example. Based on the successful experiences from the national schistosomiasis control programme in China, this model emphasizes the compliance with World Health Organization guidelines and fully considers local actual needs to promote the effectiveness and sustainability of the schistosomiasis control programme through integrating international resources and promoting China's experience to meet local needs. The successful practice of the China aid project of schistosomiasis control in Zanzibar provides strong evidence that the model is of great theoretical significance and practical value to improve the efficiency of multilateral collaboration and promote global health governance. Related Articles | Metrics | Comments（0）

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Development and preliminary application of a multiplex PCR assay for simultaneous detection of four intestinal parasites in goats LI Yilong, MU Xuanru, XU Hui, LUO Xiaoping, YU Runzi, XU Xinyi, YANG Linlin, YU Xingang, HONG Yang Chinese Journal of Schistosomiasis Control    2024, 36 (4): 376-383.   Abstract （231）      PDF（pc） （1227KB）（407）       Knowledge map    Save Objective　To develop a multiplex PCR assay for simultaneous detection of four intestinal parasites, including Giardia duodenalis, Cryptosporidium parvum, Enterocytozoon bieneusi and Moniezia, and to preliminarily evaluate its detection efficiency. Methods　Four pairs of specific primers were designed based on the conserved sequences of the corresponding genes of G. duodenalis (GenBank accession number: XM_001710026.2), C. parvum (GenBank accession number: XM_626998.1), E. bieneusi (GenBank accession number: KJ719492.1) and Moniezia (GenBank accession number: OM296991.1) retrieved from the GenBank database, and a multiplex PCR assay for simultaneous detection of G. duodenalis, C. parvum, E. bieneusi and Moniezia was developed and optimized. A total of 116 fresh goat stool samples were collected from four goat farms in Zhanjiang City, Guangdong Province during the period from October to December 2022, including 96 samples used for evaluating the detection efficacy of the multiplex PCR assay, and 20 samples as baseline controls for sample testing. Genomic DNA extracted from 96 goat stool samples was tested using the single⁃target PCR assay and the developed multiplex PCR assay, and the sensitivity, specificity, positive predictive value, and negative predictive value of the multiplex PCR assay were evaluated for detection of G. duodenalis, C. parvum, E. bieneusi and Moniezia DNA in goat stool samples with the single⁃target PCR assay as the gold standard. Results　The multiplex PCR assay developed in this study allowed simultaneous amplification of specific gene fragments of G. duodenalis, C. parvum, E. bieneusi and Moniezia, with 1 400, 755, 314 bp and 585 bp in sizes, respectively, and the detection limit was 102 and higher copies of parasite DNA clones, while the multiplex PCR assay was negative for gene amplification of Schistosoma japonicum, Fasciola hepatica, Echinococcus granulosus, Blastocystis hominis and Homalogaster paloniae. Single⁃target PCR assay and the developed multiplex PCR assay were employed to test DNA samples extracted from 96 goat stool samples, and single⁃target PCR assay tested positive in 40 goat stool samples (41.67%), including 39 positive samples tested with the multiplex PCR assay, with a mean coincidence rate of 97.50% (39/40). The multiplex PCR assay tested positive for G. duodenalis DNA in 26 goat stool samples (27.10%), C. parvum DNA in 22 samples (22.90%), E. bieneusi DNA in 24 samples (25.00%), and Moniezia in 9 samples (9.40%), which was consistent with the detection using the single⁃target PCR assay. The sensitivity, negative predictive value, and positive predictive value of the multiplex PCR assay were 96.15%, 95.83%, 100.00% and 100.00%, 98.90%, 98.92%, 100.00% and 100.00%, 100.00%, 100.00%, 100.00% and 100.00% for detection of G. duodenalis, C. parvum, E. bieneusi and Moniezia DNA in goat stool samples, respectively, if the single⁃target PCR assay served as the gold standard. Conclusion　A highly sensitive and specific multiplex PCR assay has been developed for simultaneous detection of G. duodenalis, C. parvum, E. bieneusi and Moniezia in goats, which is suitable for rapid, large⁃scale screening of intestinal parasites in sheep stool samples. Related Articles | Metrics | Comments（0）

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Genetic polymorphisms of common sandflies in selected areas of Henan Province based on DNA barcoding WANG Dan, HE Zhiquan, YANG Chengyun, LU Deling, SUN Yiying, KOU Yuanjing, QIAN Dan, ZHANG Hongwei, LIU Ying Chinese Journal of Schistosomiasis Control    2024, 36 (4): 352-360,392.   Abstract （228）      PDF（pc） （1276KB）（482）       Knowledge map    Save Objective　To characterize the species of common sandflies in Henan Province using DNA barcoding with cytochrome c oxidase subunit I (COI) gene as the molecular marker, and to analyze the genetic polymorphisms of sandflies, so as to provide insights into visceral leishmaniasis prevention and control in Henan Province. Methods　Sandfly specimens were sampled from 13 sandflies surveillance sites from 2021 to 2023 in Anyang City, Zhengzhou, Luoyang and Xuchang cities (Zhengzhou⁃Luoyang⁃Xuchang areas) where visceral leishmaniasis cases were reported and in Jiaozuo and Xinxiang cities (Jiaozuo⁃Xinxiang areas) without visceral leishmaniasis cases reported. Genomic DNA was extracted from a single sandfly, and COI gene was amplified. The amplification product was subjected to bidirectional sequencing. Following sequence assembly, the species of sandflies was characterized through sequence alignment using the BLAST tool. The intra⁃specific and inter⁃specific genetic distances of sandflies were estimated among different areas using the software Mega 11, and phylogenetic trees were created. The polymorphisms of nucleotide sequences in the sandflies COI gene were estimated using the software DnaSP. The fixation index (FST) of different geographical isolates of sandflies was calculated using the Arlequin software, and the gene flow value (Nm) was used to measure the gene flow in the sandflies populations. In addition, the population genetic structure of different geographical populations of Phlebotomus chinensis was analyzed using the STRUCTURE software. Results　A total of 978 sandflies were collected from 13 sandflies surveillance sites in Zhengzhou⁃Luoyang⁃Xuchang areas, Jiaozuo⁃Xinxiang areas and Anyang City of Henan Province from 2021 to 2023, and 475 sandflies were randomly sampled for subsequent detections. A total of 304 Ph. chinensis, 162 Se. squamirostris and 9 Se. bailyi were identified based on molecular biological detection of the COI gene, and Se. bailyi was reported for the first time in Henan Province. The intraspecific genetic distances of sandflies were 0.000 to 0.040, and the interspecific genetic distances ranged from 0.133 to 0.161. Phylogenetic analysis revealed that each of the three sandfly species was clustered into a clade. The genetic polymorphisms of Ph. chinensis populations varied among different areas, with the highest haplotype diversity (0.966 ± 0.007) and the greatest nucleotide diversity (0.011) in Zhengzhou⁃Luoyang⁃Xuchang areas, and the lowest haplotype diversity (0.720 ± 0.091) and nucleotide diversity (0.004) in Anyang City. The dominant haplotype of Ph. chinensis populations was Pch_Hap_2 in Anyang City and Jiaozuo⁃Xinxiang areas, with moderate genetic differentiation (0.05 < FST < 0.15) and frequent gene exchange (Nm value > 1) between Ph. chinensis populations sampled from Anyang City, and Jiaozuo⁃Xinxiang areas. Population genetic structure analysis showed that the dominant component of Ph. chinensis populations was K5 in Anyang City and Jiaozuo⁃Xinxiang areas. No obvious dominant haplotype was observed in Ph. chinensis populations sampled from Zhengzhou⁃Luoyang⁃Xuchang areas, which had very high genetic differentiation (FST > 0.25) and little gene exchange (Nm value <１) with Ph. chinensis populations from Anyang City, and Jiaozuo⁃Xinxiang areas, with K3 as the dominant component. In addition, there was no significant difference in the genetic polymorphism level among Se. squamirostris populations from the three areas. Conclusions 　There are Ph. chinensis, Se. squamirostris and Se. bailyi in Henan Province, and S. bailyi is recorded for the first time in Henan Province by molecular biological assays. There are different levels of genetic differentiation and gene exchange among P. chinensis populations in different areas of Henan Province. Related Articles | Metrics | Comments（0）

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Global burden of visceral leishmaniasis from 1990 to 2021 and projections up to 2035 YANG Guobing, HE Aiwei, LI Yongjun, LÜ Shan, CHEN Muxin, TIAN Liguang, LIU Qin, DUAN Lei, LU Yan, YANG Jian, LI Shizhu, ZHOU Xiaonong, WANG Jichun, ZHANG Shunxian Chinese Journal of Schistosomiasis Control    2025, 37 (1): 35-43.   Abstract （223）      PDF（pc） （1659KB）（307）       Knowledge map    Save Objective　To investigate the global burden of visceral leishmaniasis (VL) from 1990 to 2021 and predict the trends in the burden of VL from 2022 to 2035, so as to provide insights into global VL prevention and control. Methods　 The global age⁃standardized incidence, prevalence, mortality and disability⁃adjusted life years (DALYs) rates of VL and their 95% uncertainty intervals (UI) were captured from the Global Burden of Disease Study 2021 (GBD 2021) data resources. The trends in the global burden of VL were evaluated with average annual percent change (AAPC) and 95% confidence interval (CI) from 1990 to 2021, and gender⁃, age⁃, country⁃, geographical area⁃ and socio⁃demographic index (SDI)⁃stratified burdens of VL were analyzed. The trends in the global burden of VL were projected with a Bayesian age⁃period⁃cohort (BAPC) model from 2022 to 2035, and the associations of age⁃standardized incidence, prevalence, mortality, and DALYs rates of VL with SDI levels were examined with a smoothing spline model. Results　The global age⁃standardized incidence [AAPC = -0.25%, 95% CI: (-0.25%, -0.24%)], prevalence [AAPC = -0.06%, 95% CI: (-0.06%, -0.06%)], mortality [AAPC = -0.25%, 95% CI: (-0.25%, -0.24%)] and DALYs rates of VL [AAPC = -2.38%, 95% CI: (-2.44%, -2.33%)] all appeared a tendency towards a decline from 1990 to 2021, and the highest age⁃standardized incidence [2.55/105, 95% UI: (1.49/105, 4.07/105)], prevalence [0.64/105, 95% UI: (0.37/105, 1.02/105)], mortality [0.51/105, 95% UI: (0, 1.80/105)] and DALYs rates of VL [33.81/105, 95% UI: (0.06/105, 124.09/105)] were seen in tropical Latin America in 2021. The global age⁃standardized incidence and prevalence of VL were both higher among men [0.57/105, 95% UI: (0.45/105, 0.72/105); 0.14/105, 95% UI: (0.11/105, 0.18/105)] than among women [0.27/105, 95% UI: (0.21/105, 0.33/105); 0.06/105, 95% UI: (0.05/105, 0.08/105)], and the highest mortality of VL was found among children under 5 years of age [0.24/105, 95% UI: (0.08/105, 0.66/105)]. The age⁃standardized incidence (r = -0.483, P < 0.001), prevalence (r = -0.483, P < 0.001), mortality (r = -0.511, P < 0.001) and DALYs rates of VL (r = -0.514, P < 0.001) correlated negatively with SDI levels from 1990 to 2021. In addition, the global burden of VL was projected with the BAPC model to appear a tendency towards a decline from 2022 to 2035, and the age⁃standardized incidence, prevalence, mortality and DALYs rates were projected to be reduced to 0.11/105, 0.03/105, 0.02/105 and 1.44/105 in 2035, respectively. Conclusions　Although the global burden of VL appeared an overall tendency towards a decline from 1990 to 2021, the burden of VL showed a tendency towards a rise in Central Asia and western sub⁃Saharan African areas. The age⁃standardized incidence and prevalence rates of VL were relatively higher among men, and the age⁃standardized mortality of VL was relatively higher among children under 5 years of age. The global burden of VL was projected to continue to decline from 2022 to 2035. Reference | Related Articles | Metrics | Comments（0）

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Molluscicidal effect of spraying 5% niclosamide ethanolamine salt granules with drones against Oncomelania hupensis in marshland areas CAO Chunli, ZHANG Jianfeng, LI Yefang, SHEN Xuehui, HE Junyi, BAO Ziping, GUO Suying, YANG Kun, XU Jing, LI Shizhu, ZHOU Xiaonong Chinese Journal of Schistosomiasis Control    2024, 36 (5): 531-534.   Abstract （220）      PDF（pc） （959KB）（228）       Knowledge map    Save Objective　To evaluate the molluscicidal effect of spraying 5% niclosamide ethanolamine salt granules with drones against of Oncomelania hupensis snails in snail habitats in marshland areas. Methods　From September to October, 2022, marshlands were sampled from Dantu District, Zhenjiang City, Jiangsu Province as study areas, and assigned into four groups, of approximately 3 000 m2 per group. In Group A, environmental cleaning was performed, followed by spraying 5% niclosamide ethanolamine salt granules with knapsack sprayers at a dose of 40 g/m2, and in Group B, 5% niclosamide ethanolamine salt granules were sprayed with knapsack sprayers at a dose of 40 g/m2 without environmental cleaning, while in Group C, environmental cleaning was conducted, followed by spraying 5% niclosamide ethanolamine salt granules with drones at a dose of 40 g/m2, and in Group D, 5% niclosamide ethanolamine salt granules were sprayed with drones at a dose of 40 g/m2 without environmental cleaning. Then, the study areas in each group were equally divided into six blocks, with Block 1 for baseline surveys and blocks 2 to 6 for snail surveys 1, 3, 5, 7, 14 days following chemical treatment. The mortality of snails and the reduction of the density of living snails were calculated. Results　A total of 132 frames were surveyed during the period from September to October 2022, and the occurrence of frames with living snails and means density of living snails were 61.36% (81/132) and 1.58 snails/0.1 m2, respectively. The overall mortality rates of snails were 43.02% (77/179), 38.69% (77/199), 47.78% (86/180) and 31.02% (58/187) 14 days following chemical treatment in groups A, B, C and D, respectively ([χ2] = 11.646, P < 0.05), and there were differences detected in the snail mortality between group A and D, and between groups C and D (both Padjusted values < 0.05). The adjusted mortality rates of snails were 37.42%, 36.07%, 38.85% and 40.40% in groups A, B, C and D 14 days post⁃treatment, and the density of living snails decreased by 48.10%, 63.29%, 67.09% and 69.62% 14 days post⁃treatment relative to pre⁃treatment, respectively. Conclusions　Chemical treatment with drones is feasible for O. hupensis snail control in marshland areas; however, the molluscicidal effect of spraying 5% niclosamide ethanolamine salt granules with drones is comparable to spraying chemicals manually in marshland areas regardless of environmental cleaning. Related Articles | Metrics | Comments（0）

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Spatiotemporal clustering and hot spot analysis of visceral leishmaniasis in Gansu Province from 1993 to 2023 YU Dawei, HE Aiwei, FENG YU, YANG Guobing, YANG Chengming, LI Fan Chinese Journal of Schistosomiasis Control    2024, 36 (4): 334-338,387.   Abstract （215）      PDF（pc） （1535KB）（425）       Knowledge map    Save Objective　To investigate the spatiotemporal clustering characteristics of the reported incidence of visceral leishmaniasis (VL) in Gansu Province from 1993 to 2023, so as to provide insights into the containment of VL and prevention of VL recurrence. Methods　County (district)⁃level epidemical data of VL in Gansu Province from 1993 to 2023 were collected, and the geographical information database of reported VL incidence in Gansu Province was created according to the county⁃level administrative code and electronic maps in Gansu Province. In addition, the spatial autocorrelation analysis and hot spot analysis of the reported VL incidence were performed in Gansu Province using the software ArcGIS 10.8. Results　A total of 2 597 VL cases were reported in Gansu Province from 1993 to 2023, with an annual average incidence rate of 3.036/105. Spatial autocorrelation analysis showed spatial clustering of the reported VL incidence in Gansu Province (Moran’s I = 0.605, Z = 5.240, P < 0.001), appearing high⁃high clustering features (Getis⁃Ord G = 0.080, Z = 4.137, P < 0.001), and high⁃high clustering of the reported incidence of VL was identified in Diebu County, Dangchang County, Zhouqu County and Wenxian County. Hot spot analysis showed hot⁃spot areas of the reported VL incidence in Dangchang County, Zhouqu County, Wudu District and Wen County along the Bailong River basins and cold⁃spot areas in Qin’an County and Gangu County. Conclusions　There was spatial clustering and hot spots of the reported VL incidence in Gansu Province from 1993 to 2023. Intensified surveillance and control is required to prevent the spread of VL. Related Articles | Metrics | Comments（0）

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Molecular characteristics of Japanese encephalitis virus carried by Culex tritaeniorhynchus in Dongchuan District, Kunming City, Yunnan Province GU Yangyang, HE Yuwen, CHEN Yiju, YANG Zhenxing, LI Nan, LÜ Shunyan, ZHU Yantao, RUAN Fangchao, WANG Jiali, WANG Jinglin Chinese Journal of Schistosomiasis Control    2024, 36 (4): 361-369.   Abstract （210）      PDF（pc） （2400KB）（678）       Knowledge map    Save Objective　To isolate the Japanese encephalitis virus carried by Culex tritaeniorhynchus in Dongchuan District of Yunnan Province and analyze its molecular characteristics, so as to provide insights into the prevention and control of Japanese encephalitis in Yunnan Province. Methods　Mosquito specimens were collected using mosquito⁃trapping lamps from pig farms in Batang Village and Xiaoxin Village, Dongchuan District, Kunming City, Yunnan Province in July 2016, and the mosquito species was identified according to the mosquito morphology. Then, 60 to 100 mosquitoes of each species served as a group and were ground. Baby hamster kidney⁃21 (BHK⁃21) cells and Aedes albopictus clone C6/36 cells were used for virus isolation, and positive isolates were identified using flavivirus primers. The positive isolates were amplified using reverse transcription polymerase chain reaction (RT⁃PCR) assay with 15 pairs of specific primers covering the full length of the genotypeⅠJapanese encephalitis virus, and DNA sequence assembly was performed using the software SeqMan in the DNASTAR package. The obtained sequences were aligned with the complete sequences of 38 Japanese encephalitis virus downloaded from the GenBank with the software MegAlign, and the nucleotide and amino acid homology analyses of the obtained sequences were performed. The difference in amino acid sites was analyzed with the software GeneDoc, and phylogenetic trees were created based on the sequences of the coding region and E protein of the isolated Japanese encephalitis virus with the software Mega X. In addition, the secondary and tertiary structures of the E protein of the Japanese encephalitis virus were predicted using the online tool SOPMA and the software Swiss⁃Model. Results　A total of 5 820 mosquitoes were collected and 3 843 Cx. tritaeniorhynchus (66.03%) were identified according to the mosquito morphology. A positive virus isolate, termed YNDC55⁃33, was isolated from Cx. tritaeniorhynchoides following batches of virus isolation from mosquito specimens, and cytopathic effect was observed following inoculation into BHK⁃21 and C6/36 cells. The YNDC55⁃33 virus isolate was successfully amplified with the flavivirus primes, and a long sequence containing 300 nucleotides was obtained. Following sequence alignment using the BLAST tool, the sequence of the YNDC55⁃33 virus isolate had high homology with that of the genotypeⅠJapanese encephalitis virus. A long sequence with 10 845 nucleotides in length, which encoded 3 432 amino acids, was obtained by splicing the full sequence of the YNDC55⁃33 virus isolate. Phylogenetic analysis based on the whole⁃genome sequence and E gene sequence of the YNDC55⁃33 virus isolate showed that the new YNDC55⁃33 virus isolate was most closely related to the genotypeⅠGuizhou isolate (GenBank accession number: HM366552), with nucleotide homology of 98.5% and amino acid homology of 99.4%, and the YNDC55⁃33 virus isolate shared 97.96% ± 0.33% nucleotide homology and 99.35% ± 0.08% amino acid homology with other genotypeⅠJapanese encephalitis virus isolates, and < 90% nucleotide homology and < 98% amino acid homology with other genotypes of Japanese encephalitis virus. The YNDC55⁃33 virus isolate and the live attenuated virus vaccine candidate SA14⁃14⁃2 isolate differed at 16 amino acid sites on E gene, and 7 out of 8 key amino acid sites related to neurovirulence. The secondary and tertiary structures of the E protein of the YNDC55⁃33 virus isolate were predicted to be characterized by random coils. Conclusions　A genotype I Japanese encephalitis virus was isolated from Cx. tritaeniorhynchus in Dongchuan District, Kunming City. This virus isolate and the live attenuated virus vaccine candidate SA14⁃14⁃2 isolate does not differ at antigenic epitopes⁃related key amino acid sites, and the major protein structure of the virus isolate is random coils. This study adds new data for the epidemiological distribution of Japanese encephalitis virus in Yunnan Province, which may provide insights into the prevention and control of Japanese encephalitis in the province. Related Articles | Metrics | Comments（0）

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Physiological characteristics of Bacillus thuringiensis subspecies israelensis with double mutations of cwlE and sigK and its activity against larvae of Culex pipiens pallens HUANG Lixin, HAN Guangjie, LI Chuanming, LIN Manman, ZHANG Nan, XU Jian Chinese Journal of Schistosomiasis Control    2024, 36 (6): 606-613.   Abstract （206）      PDF（pc） （10631KB）（115）       Knowledge map    Save Objective　To investigate the physiological characteristics of Bacillus thuringiensis subspecies israelensis (Bti) with double mutations of cwlE and sigK genes and to assess the activity of Bti against larvae of Culex pipiens pallens under different external factors, so as to provide the theoretical evidence for the use of engineered bacteria of Bti for effective mosquito control.  Methods　B. thuringiensis wild⁃type strain Bt⁃59 and Bt⁃59 strain with cwlE mutation [Bt⁃59 (ΔcwlE)] were cultured in nutrient broth media for 24 hours, and Bt⁃59 strains with sigK mutation [Bt⁃59 (ΔsigK)] and double mutations of cwlE and sigK [Bt⁃59 (ΔcwlE⁃sigK)] were cultured in nutrient broth media for 48 hours. Then, 5 μL of culture media were transferred to glass sides, and cell morphology and mother cell lysis were observed under an optical microscope. The optical densities of Bti strain culture media were measured at different time points of culture, and the growth curves of Bt⁃59, Bt⁃59 (ΔcwlE), Bt⁃59 (ΔsigK), and Bt⁃59 (ΔcwlE⁃sigK) strains were plotted. The differences in carbon source metabolism of four Bti strains were analyzed using the Biolog microplate culture method, and the metabolic activity of these strains was estimated with average well color development (AWCD). The fermentation media of these four Bti strains were diluted into final concentrations of 2.000, 1.000, 0.500, 0.250, and 0.125 μL/L, and the median lethal concentrations (LC50 values) of these four strains against the third instar larvae of Cx. pipiens pallens were determined. In addition, the fermentation media of Bti strains were processed as follows: pH adjusted to 5, 7 and 9; treated at 30, 40 ℃ and 50 ℃ for 12 hours; and exposed to irradiation with ultraviolet lights for 0 hour and 6 hours. Then, 20 third instar larvae of Cx. pipiens pallens were exposed to the above processed fermentation media at a final concentration of 1 μL/L in 200 mL of water at 26 ℃ for 24 hours, and the mosquito mortality was estimated to evaluate the effects of pH, temperature and ultraviolet irradiation on the larvicidal activity of four Bti strains.  Results　The growth curves of the Bt⁃59 strain and its mutants shared a similar changing trend, and both experienced a stable phase 6 hours post⁃culture. Both spores and crystal proteins were found in Bt⁃59 and Bt⁃59 (ΔcwlE) cells, and only crystal proteins were found in Bt⁃59 (ΔsigK) and Bt⁃59 (ΔcwlE⁃sigK) cells. No lysis was found in the cell wall of the Bt⁃59 (ΔcwlE⁃sigK) strain, and the crystal protein was embedded in the mother cell. Biolog microplate culture assay showed that the AWCD values of four Bti strains showed a similar changing trend over time, and 33 carbon sources were found to be metabolized by all of the four strains, including dextrin, D⁃maltose and D⁃trehalose. The LC50 values of the fermentation media of Bt⁃59, Bt⁃59 (ΔcwlE), Bt⁃59 (ΔsigK), and Bt⁃59 (ΔcwlE⁃sigK) strains were 0.60, 0.51, 0.70 μL/L and 0.72 μL/L against Cx. pipiens pallens, respectively. The adjusted mortality of larval Cx. pipiens pallens reduced by 76.60%, 76.00%, 66.67%, and 0 following exposure to the fermentation media of Bt⁃59, Bt⁃59 (ΔcwlE), Bt⁃59 (ΔsigK), and Bt⁃59 (ΔcwlE⁃sigK) strains at a pH of 5 relative to at a pH of 7, and the adjusted mortality reduced by 49.02%, 51.06%, 36.36%, and 4.44% following 6⁃hour exposure to ultraviolet irradiation relative to 0⁃hour exposure, while the adjusted mortality was 68.33% to 83.33% following treatment with the fermentation media of four Bti strains at different temperatures.  Conclusions　Bt⁃59 (ΔcwlE⁃sigK) strains  do not generate spores, and the absence of cwlE and sigK does not affect the growth, carbon source metabolism, and larvicidal activity of Bti strains against larval Cx. pipiens pallens. Cell wall embedding of Bt⁃59 (ΔcwlE⁃sigK) strains may protect larvicidal crystal proteins of Bti strains from external environmental factors, including ultraviolet irradiation, and pH alteration. Related Articles | Metrics | Comments（0）

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Knowledge, attitudes and practices towards scrub typhus control and associated influencing factors among residents in Longling County, Yunnan Province in 2023 ZHOU Yu, YANG Shujuan, YANG Yuan, HE Yan, YUAN Shulian, CHEN Zhaowen, REN Tianguang Chinese Journal of Schistosomiasis Control    2024, 36 (5): 507-513.   Abstract （204）      PDF（pc） （1059KB）（217）       Knowledge map    Save Objective　To investigate the knowledge, attitudes and practices （KAP） towards scrub typhus control and analyze the influencing factors among residents in Longling County, Yunnan Province in 2023, so as to provide insights into management of scrub typhus in the county.  Methods　Two townships were randomly sampled from Longling County, Baoshan City, Yunnan Province in July 2023, and 2 to 3 administrative villages were randomly selected from each township. Then, 20 to 40 households were randomly selected from each village, and 1 to 2 villagers were surveyed in each household. Residents' KAP towards scrub typhus control was investigated, and factor affecting residents' KAP towards scrub typhus control were identified with independent samples t test or analysis of variance （ANOVA） and multiple linear regression analysis.  Results　A total of 417 questionnaires were allocated, and 410 valid questionnaires were recovered, with an effective recovery rate of 98.32%. Of all respondents, 65.85% （270/410） heard of scrub typhus but were not familiar with it, and 12.68% （52/410） and 1.95% （8/410） were familiar and very familiar with it, respectively. Residents mainly acquired scrub typhus control knowledge via their relatives and friends. The knowledge, attitude, and behavior scores of the respondents with regard to scrub typhus were （34.14 ± 13.07）,  （55.04 ± 6.69）, and  （21.40 ± 5.61）, respectively, and the total score for knowledge, belief, and behavior in relation to scrub typhus prevention and control was （110.57 ± 18.80）. Univariate analysis revealed that age （F = 3.12, P < 0.05）, education （F = 10.77, P < 0.05）, occupation （F = 4.89, P < 0.05）, frequency of outdoor activities （F = 3.61, P < 0.05）, and type of place of residence （t = 1.33, P < 0.05） were the factors that influenced the participants' scores for knowledge of the prevention and control of scrub typhus. Multiple linear regression analysis revealed that literacy level （β = 10.20 to 16.71, P < 0.05） and category of residence （β = -7.23, P < 0.05） were the factors that influenced residents' current knowledge and trust behavior in relation to scrub typhus. Conclusions　Place of residence and educational level are critical factors affecting scrub typhus control among residents in Longling County, Yunnan Province. Intensified health education pertaining to scrub typhus control and appropriate behavioral interventions are required among residents living in urban areas, with a low educational level and frequent outdoor activities.  Related Articles | Metrics | Comments（0）

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Construction of a visual intelligent identification model for Oncomelania hupensis robertsoni in Yunnan Province based on the EfficientNet⁃B4 model BAI Shaowen, ZHOU Jihua, DONG Yi, ZHANG Jianfeng, SHI Liang, YANG Kun Chinese Journal of Schistosomiasis Control    2024, 36 (6): 555-561.   Abstract （203）      PDF（pc） （7830KB）（188）       Knowledge map    Save Objective　To construct a visual intelligent recognition model for Oncomelania hupensis robertsoni in Yunnan Province based on the EfficientNet⁃B4 model, and to evaluate the impact of data augmentation methods and model hyperparameters on the recognition of O. hupensis robertsoni. Methods　A total of 400 O. hupensis robertsoni and 400 Tricula snails were collected from Yongsheng County, Yunnan Province in June 2024, and snail images were captured following identification and classification of 300 O. hupensis robertsoni and 300 Tricula snails. A total of 925 O. hupensis robertsoni images and 1 062 Tricula snail images were collected as a dataset and divided into a training set and validation set in a ratio of 8∶2, while 352 images captured from the other 100 O. hupensis robertsoni and 354 images from 100 Tricula snails served as an external test set. All acquired images were subjected to preprocessing, including cropping and resizing. Three data augmentation approaches were employed, including baseline, Mixup and Gaussian blurring, and model hyperparameters included two optimization algorithms of adaptive moment estimation (Adam) and stochastic gradient descent (SGD), two loss functions of focal loss and cross entropy loss, and two learning rate decay strategies of cosine annealing and multi⁃step. The intelligent recognition models of O. hupensis robertsoni and Tricula snails were constructed based on the EfficientNet⁃B4 model, and 7 training strategy groups were generated by combinations of different data augmentation approaches and hyperparameters. The performance of intelligent recognition models was tested with external test sets, and evaluated with accuracy, precision, recall, F1 score, loss, Youden's index, and the area under the receiver operating characteristic curve (AUC) under different training strategies. Results　The variation of loss values was comparable among intelligent recognition models with different data augmentation approaches. The Group 4 model constructed with Mixup and Gaussian blurring data augmentation approaches showed the optimal performance, with an accuracy of 90.38%, precision of 90.07%, F1 score of 89.44%, Youden's index of 0.81 and AUC values of 0.961 in the external test set. The accuracy of models using the SGD optimizer reduced by 29.16% as compared to those using the Adam optimizer ([χ2] = 81.325, P < 0.001), and the accuracy of models using the cross entropy loss function reduced by 0.80% as compared to the Group 4 model ([χ2] = 3.147, P > 0.05), while the accuracy of models using the multi⁃step learning rate decay strategy increased by 0.65% as compared to the Group 4 model ([χ2] = 0.208, P > 0.05). In addition, the model with the baseline + Mixup + Gaussian blurring data augmentation approach and hyperparameters of Adam optimizer, focal loss function and multi⁃step learning rate decay strategy showed the highest performance, with an accuracy of 91.03%, precision of 91.97%, recall of 88.11%, F1 score of 90.00%, Youden's index of 0.82 and AUC values of 0.969 in external test set, respectively. Conclusions　The intelligent recognition model of O. hupensis robertsoni based on EfficientNet⁃B4 model is accurate for identification of O. hupensis robertsoni and Tricula snails in Yunnan Province. Related Articles | Metrics | Comments（0）

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Prediction of potential geographic distribution of Oncomelania hupensis in Yunnan Province using random forest and maximum entropy models ZHANG Zongya, DU Chunhong, ZHANG Yun, WANG Hongqiong, SONG Jing, ZHOU Jihua, WANG Lifang, SUN Jiayu, SHEN Meifen, CHEN Chunqiong, JIANG Hua, YAN Jiaqi, FENG Xiguang, WANG Wenya, QIAN Peijun, XUE Jingbo, LI Shizhu, DONG Yi Chinese Journal of Schistosomiasis Control    2024, 36 (6): 562-571,613.   Abstract （202）      PDF（pc） （11078KB）（167）       Knowledge map    Save Objective　To predict the potential geographic distribution of Oncomelania hupensis  in Yunnan Province using random forest (RF) and maximum entropy (MaxEnt) models, so as to provide insights into O. hupensis surveillance and control in Yunnan Province.  Methods　The O. hupensis snail survey data in Yunnan Province from 2015 to 2016 were collected and converted into O. hupensis snail distribution site data. Data of 22 environmental variables in Yunnan Province were collected, including twelve climate variables (annual potential evapotranspiration, annual mean ground surface temperature, annual precipitation, annual mean air pressure, annual mean relative humidity, annual sunshine duration, annual mean air temperature, annual mean wind speed, ≥ 0 ℃ annual accumulated temperature, ≥ 10 ℃ annual accumulated temperature, aridity and index of moisture), eight geographical variables (normalized difference vegetation index, landform type, land use type, altitude, soil type, soil texture⁃clay content, soil texture⁃sand content and soil texture⁃silt content) and two population and economic variables (gross domestic product and population).  Variables were screened with Pearson correlation test and variance inflation factor (VIF) test. The RF and MaxEnt models and the ensemble model were created using the biomod2 package of the software R 4.2.1, and the potential distribution of O. hupensis snails after 2016 was predicted in Yunnan Province. The predictive effects of models were evaluated through cross⁃validation and independent tests, and the area under the receiver operating characteristic curve (AUC), true skill statistics (TSS) and Kappa statistics were used for model evaluation. In addition, the importance of environmental variables was analyzed, the contribution of environmental variables output by the models with AUC values of > 0.95 and TSS values of > 0.85 were selected for normalization processing, and the importance percentage of environmental variables was obtained to analyze the importance of environmental variables. Results　Data of 148 O. hupensis snail distribution sites and 15 environmental variables were included in training sets of RF and MaxEnt models, and both RF and MaxEnt models had high predictive performance, with both mean AUC values of > 0.9 and all mean TSS values and Kappa values of > 0.8, and significant differences in the AUC (t = 19.862, P < 0.05), TSS (t = 10.140, P < 0.05) and Kappa values (t = 10.237, P < 0.05) between two models. The AUC, TSS and Kappa values of the ensemble model were 0.996, 0.954 and 0.920, respectively. Independent data verification showed that the AUC, TSS and Kappa values of the RF model and the ensemble model were all 1, which still showed high performance in unknown data modeling, and the MaxEnt model showed poor performance, with TSS and Kappa values of 0 for 24% (24/100) of the modeling results. The modeling results of 79 RF models, 38 MaxEnt models and their ensemble models with AUC values of > 0.95 and TSS values of > 0.85 were included in the evaluation of importance of environmental variables. The importance of annual sunshine duration (SSD) was 32.989%, 37.847% and 46.315% in the RF model, the MaxEnt model and their ensemble model, while the importance of annual mean relative humidity (RHU) was 30.947%, 15.921% and 28.121%, respectively. Important environment variables were concentrated in modeling results of the RF model, dispersed in modeling results of the MaxEnt model, and most concentrated in modeling results of the ensemble model. The potential distribution of O. hupensis snails after 2016 was predicted to be relatively concentrated in Yunnan Province by the RF model and relatively large by the MaxEnt model, and the distribution of O. hupensis snails predicted by the ensemble model was mostly the joint distribution of O. hupensis snails predicted by RF and MaxEnt models.  Conclusions 　Both RF and MaxEnt models are effective to predict the potential distribution of O. hupensis snails in Yunnan Province, which facilitates targeted O. hupensis snail control.  Related Articles | Metrics | Comments（0）

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Hepatic T cell subtypes and functional analysis among alveolar echinococcosis patients using single⁃cell RNA sequencing CHEN Si, WANG Xiangqian, JIA Wanzhong, CAI Qigang, ZHANG Xueyong, ZHANG Qiang, ZHENG Haibo, ZHU Linghong, LI Bing, WANG Wei, HAN Xiumin Chinese Journal of Schistosomiasis Control    2024, 36 (5): 481-493.   Abstract （201）      PDF（pc） （4415KB）（1245）       Knowledge map    Save Objective　To investigate T cell subtypes and their functions in liver immune microenvironments among patients with alveolar echinococcosis (AE) using single⁃cell RNA sequencing (scRNA⁃seq).  Methods　Four AE patients that were admitted to Qinghai Provincial People's Hospital in 2023 for hepatic surgery for the first time were enrolled, and liver specimens were sampled 1 cm (peri⁃lesion, PL group) and > 5 cm from AE lesions (distal lesion, DL group) among each patient. Finally, a total of eight liver specimens were sampled from four AE patients for scRNA⁃seq analysis. Genome and transcriptome data of liver specimens were processed using the software Cell Ranger and R package. Differentially expressed genes (DEGs) and their biological functions were analyzed using gene ontology (GO) enrichment analysis and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis, and the primary intercellular communication patterns and interaction mechanisms were identified among T cell subtypes in liver specimens using the CellChat package. In addition, the developmental stages of T cells were subjected to trajectory analysis with the monocle package to investigate the expression of genes associated with cell growth and tumor transformation, and to predict the developmental trajectories of T cells. Results　All four AE patients were female, with a mean age of (25.00 ± 9.06) years, and there were three cases from Jiuzhi County, Golog Tibetan Autonomous Prefecture and one case from Chengduo County, Yushu Tibetan Autonomous Prefecture, Qinghai Province. The viability of single⁃cell samples from eight liver specimens was 90.41% to 96.33%, and a total of 81 763 cells were analyzed, with 19 cell types annotated. Of these cell types, 13 were immune cells (87.60%), and T cells (33.13%), neutrophils (15.40%), and natural killer cells (11.92%) were the three most common cell types. Re⁃clustering of 27 752 T cells and proliferative T cells identified 10 distinct T cell subtypes, with CD8+ cytotoxic T cells (23.43%), CD8+ naive T cells (12.80%), and CD4+ effector memory T cells (17.73%) as dominant cell types. The proportions of T helper 2 (Th2) cells (5.19% vs. 3.63%; [χ2]  = 38.35, P < 0.01) and CD4+ effector memory T cells (21.59% vs. 13.67%; [χ2]  = 244.70, P < 0.01) were significantly higher in liver specimens in the PL group than in the DL group, and the proportion of CD4+ helper T cells was significantly lower in the PL group than in the DL group (7.50% vs. 14.75%; [χ2]  = 330.52, P < 0.01). KEGG pathway analysis revealed that Th2 cells were significantly enriched in cell apoptosis and multiple cancer⁃associated pathways, and CD4+ effector memory T cells were significantly enriched in the regulation of cytokines and chronic inflammation, while CD4+ helper T cells were significantly enriched in immune responses regulation. Trajectory analysis of T cells showed that CD4+ helper T cells were at an earlier developmental stage relative to Th2 cells and CD4+ effector memory T cells, and the expression of inhibitor of DNA binding 3 (ID3), thioredoxin interacting protein (TXNIP), Bcl2⁃associated athanogene 3 (BAG3) and heat shock protein family B (small) member 1 (HSPB1) genes appeared a tendency towards a decline over time. Conclusions　CD4+ effector memory T cells and CD8+ cytotoxic T cells are primary interacting cells in the liver specimens of AE patients. Reduced expression of Th2 cells and CD4+ helper T cells contributes to an inhibitory immune microenvironment, which promotes immune evasion by Echinococcus multilocularis, and Th2 cells are significantly enriched in multiple cancer⁃associated pathways, which may be linked to the invasive growth of E. multilocularis. Related Articles | Metrics | Comments（0）

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Spatiotemporal distribution of newly diagnosed echinococcosis patients in Qinghai Province from 2016 to 2022 CUI Xinlu, MA Xiao, LIU Na, LIU Jia, LEI Wen, WU Shusheng, QIN Xianglan, CAIRENNYIMA, GONG Chunhua, MO Xiaojin, YANG Shijie, ZHANG Ting, CAO Li Chinese Journal of Schistosomiasis Control    2024, 36 (5): 474-480.   Abstract （198）      PDF（pc） （1533KB）（468）       Knowledge map    Save Objective　To investigate the spatiotemporal distribution characteristics and potential influencing factors of newly diagnosed echinococcosis cases in Qinghai Province from 2016 to 2022, so as to provide insights into the formulation of the echinococcosis control strategy in Qinghai Province. Methods　The number of individuals screened for echinococcosis, number of newly diagnosed echinococcosis cases, number of registered dogs and number of stray dogs were captured from the annual reports of echinococcosis control program in Qinghai Province from 2016 to 2022, and the detection of newly diagnosed echinococcosis cases was calculated. The number of populations, precipitation, temperature, wind speed, sunshine hours, average altitude, number of year⁃end cattle stock, number of year⁃end sheep stock, gross domestic product (GDP) per capita, and number of village health centers in each county (district) of Qinghai Province were captured from the Qinghai Provincial Statistical Yearbook, and county⁃level electronic maps in Qinghai Province were downloaded from the National Platform for Common Geospatial Information Services. The software ArcGIS 10.8 was used to map the distribution of newly diagnosed echinococcosis cases in Qinghai Province, and the spatial autocorrelation analysis of newly diagnosed echinococcosis cases was performed. In addition, the space⁃time scan analyses of number of individuals screened for echinococcosis, number of newly diagnosed echinococcosis cases and geographical coordinates in Qinghai Province were performed with the software SaTScan 10.1.2, and the spatial stratified heterogeneity of the detection of newly diagnosed echinococcosis cases was investigated with the software GeoDetector. Results　A total of 6 569 426 residents were screened for echinococcosis in Qinghai Province from 2016 to 2022, and 5 924 newly diagnosed echinococcosis cases were found. The detection of newly diagnosed echinococcosis cases appeared a tendency towards a decline over years from 2016 to 2022 ([χ2] = 11.107, P < 0.01), with the highest detection in Guoluo Tibetan Autonomous Prefecture in 2017 (82.12/105). There were spatial clusters in the detection of newly diagnosed echinococcosis cases in Qinghai Province from 2016 to 2018 (Moran's I = 0.34 to 0.65, all Z values > 1.96, all P values < 0.05), and the distribution of newly diagnosed echinococcosis cases appeared random distribution from 2019 to 2022 (Moran's I = -0.09 to 0.04, all Z values < 1.96, all P values > 0.05). Local spatial autocorrelation analysis showed high⁃high clusters and low⁃low clusters in the detection of new diagnosed echinococcosis cases in Qinghai Province from 2016 to 2022, and space⁃time scan analysis showed that the first most likely cluster areas of newly diagnosed echinococcosis cases in Qinghai Province from 2016 to 2022 were mainly distributed in Yushu Tibetan Autonomous Prefecture and Guoluo Tibetan Autonomous Prefecture. GeoDetector⁃based analysis of the driving factors for the spatial stratified heterogeneity of detection of newly diagnosed echinococcosis cases in Qinghai Province showed that average altitude, number of village health centers, number of cattle and sheep stock, GDP per capita, annual average sunshine hours, and annual average temperature had a strong explanatory power for the spatial distribution of newly diagnosed echinococcosis cases, with q values of 0.630, 0.610, 0.600, 0.590, 0.588, 0.537 and 0.526, respectively. Conclusions　The detection of newly diagnosed echinococcosis cases appeared a tendency towards a decline in Qinghai Province over years from 2016 to 2022, showing spatial clustering. Targeted control measures are required in cluster areas of newly diagnosed echinococcosis cases for further control of the disease.  Related Articles | Metrics | Comments（0）

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Surveillance of parasitic infections in market⁃sold aquatic products and knowledge and practice towards food⁃borne parasitic diseases among residents in Shanghai Municipality from 2020 to 2023 DAI Simin, YU Qing, WANG Zhenyu, ZHANG Yaoguang, YANG Jiawei, WEI Zixin, MA Xiaojiang, ZHU Qian, CHEN Jian, PAN Hao, WU Huanyu Chinese Journal of Schistosomiasis Control    2024, 36 (6): 631-636.   Abstract （198）      PDF（pc） （5114KB）（157）       Knowledge map    Save Objective　To investigate the prevalence of parasitic infections in market⁃sold aquatic products in Shanghai Municipality, and to understand the knowledge and practice towards food⁃borne parasitic diseases among residents, so as to provide insights into the surveillance and control of food⁃borne parasitic diseases. Methods　Freshwater products, seawater products and pickled products were randomly obtained from agricultural trade markets, supermarkets, retail stores and restaurants in Huangpu, Putuo, Minhang and Qingpu districts of Shanghai Municipality from 2020 to 2023. Parasite metacercariae and larvae were detected in these aquatic products using pressing method, digestion method and the dissection method, and the detection of parasitic infection was compared in different types of aquatic products. In addition, the knowledge and practice towards food⁃borne parasitic diseases were investigated among residents aged 10⁃80 years old who randomly selected from agricultural trade markets, supermarkets, community streets and other population concentration areas in these four districts by questionnaire in 2023, and the awareness of food⁃borne parasitic diseases knowledge and percentage of healthy behaviors formation were analyzed. Results　A total of 2 109 aquatic products sampled from Huangpu, Putuo, Minhang and Qingpu districts of Shanghai Municipality from 2020 to 2023 were detected, and there were 317 products detected with parasitic infections, with an overall detection rate of 15.03%. There were 8 products detected with parasitic infections in 1 221 freshwater products, with a detection rate of 0.66%, and Clonorchis sinensis was the predominant parasite, which was detected in Pseudorasbora parva, Rhodeus amarus and Carassius auratus. There were 82 products detected with parasitic infections in 501 seawater products, with a detection rate of 16.37%, and Anisakis was the predominant parasite, which was detected in Trichiurus lepturus, Larimichthys polyactis, Pneumatophorus japonicus, Collchthys lucidus, Mugil cephalus, Larimichthys crocea, Scomberomorus niphonius, Stromateoides argenteus and Cololabis saira. There were 227 products detected with parasitic infections in 387 pickled products, with a detection rate of 58.66%, and the prevalence rates of Echinostoma metacercariae were 76.27% (225/295) in Bullacta exarata and 11.11% (2/18) in crab pastes, respectively ([χ2] = 159.511, P < 0.05). No Paragonimus infection was found in freshwater shrimps, crabs and pickled products, and no Diphyllobothrium latum larvae infection was detected in freshwater and seawater fish. Questionnaire surveys showed that the awareness of food⁃borne parasitic diseases knowledge was 79.00% (222/281), and the percentages of washing hands before and after meals, not drinking filtered water or tap water directly, not eating raw or semi⁃raw food, being willing to change special dietary preferences or bad living habits for health, and being willing to learn more about food⁃borne parasitic diseases knowledge were 99.64% (280/281), 72.24% (203/281), 56.23% (158/281), 96.80% (272/281) and 97.51%(274/281) among residents living in Huangpu, Putuo, Minhang and Qingpu districts, respectively. Conclusions　There are food⁃borne parasite contaminations in market⁃sold aquatic products in Shanghai Municipality. Although residents are aware of food⁃borne parasitic diseases knowledge, sustainable surveillance of food⁃borne parasitic diseases and improved health education are required to minimize the risk of human parasitic infections. Reference | Related Articles | Metrics | Comments（0）

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Laboratory malaria re⁃examination and evaluation of malaria diagnostic capability in Shanghai Municipal Malaria Diagnostic Reference Laboratory from 2017 to 2022 ZHANG Yaoguang, WANG Zhenyu, ZHU Min, JIANG Li, ZHU Qian, MA Xiaojiang, YU Qing, CHEN Jian Chinese Journal of Schistosomiasis Control    2024, 36 (5): 521-526.   Abstract （194）      PDF（pc） （1046KB）（214）       Knowledge map    Save Objective　To evaluate the malaria diagnostic capability in Shanghai Municipal Malaria Diagnostic Reference Laboratory from 2017 to 2022 and to analyze factors affecting the diagnosis results, so as to provide the scientific evidence for increasing the laboratory malaria diagnostic capability during the post⁃elimination stage. Methods　Plasmodium⁃negative blood smears were randomly sampled using a proportional sampling method each quarter during the period from 2017 to 2022 and scored by Shanghai Municipal Malaria Diagnostic Reference Laboratory. Malaria cases' blood samples from district centers for disease control and prevention in Shanghai Municipality were re⁃reviewed using microscopy and multiplex PCR assay to evaluate the capability of malaria diagnosis. Results　A total of 7 746 quality control blood smears were collected from district centers for disease control and prevention in Shanghai Municipality from 2017 to 2022, with a mean score of (76.74 ± 14.34) points and a qualification rate of 86.65% (6 712/7 746). A total of 387 blood smears were re⁃reviewed from 2017 to 2022, with an overall coincidence of 96.38% (373/387) for malaria diagnosis and 95.06% (308/324) for parasite species identification, and there were no significant differences in the coincidence for either malaria diagnosis ([χ2] = 2.57, P > 0.05) or parasite species identification among years ([χ2] = 1.04, P > 0.05). A total of 384 whole blood samples were collected from district centers for disease control and prevention, and the detection of whole blood samples was 70.31% (270/384) in district centers for disease control and prevention. All 384 whole blood samples were re⁃reviewed by Shanghai Municipal Malaria Diagnostic Reference Laboratory using a multiplex PCR assay from 2017 to 2022, with an overall coincidence of 94.07% (254/270) for malaria diagnosis and 99.55% (223/224) for parasite species identification, and there were no significant differences in the coincidence for either malaria diagnosis ([χ2] = 5.77, P > 0.05) or parasite species identification among years ([χ2] = 8.37, P > 0.05). The overall coincidence rates of Plasmodium⁃positive and negative whole blood samples were 100.00% (224/224) and 65.22% (30/46) in district centers for disease control and prevention, with a significant difference ([χ2] = 82.82, P < 0.001), and there was a significant difference in the coincidence rate for identification of P. falciparum, P. vivax, P. malariae and P. ovale ([χ2] = 24.28, P < 0.001). A total of 1 584 blind blood smears subjected to microscopic examinations by centers for disease control and prevention and medical institutions across all districts in Shanghai Municipality from 2017 to 2022, with a 96.15% (1 523/1 584) correct rate for malaria diagnosis and 85.07% (1 003/1 179) for parasite species identification, and there were significant differences in the correct rate of both malaria diagnosis ([χ2] = 20.98, P < 0.001) and parasite species identification among years ([χ2] = 70.77, P < 0.001). A total of 320 blind nucleic acid samples from malaria cases were tested, with a 99.38% (318/320) correct rate for malaria diagnosis and 100.00% (225/225) for parasite species identification, and there was no significant difference in the correct rate of malaria diagnosis among years ([χ2] = 6.04, P > 0.05). Conclusions　There were still shortcomings in blood smears preparation, microscopic examinations and nucleic acid testing in centers for disease control and prevention across all districts in Shanghai Municipality from 2017 to 2022. A greater role in the quality control of malaria diagnosis is recommended for Shanghai Municipal Malaria Diagnostic Reference Laboratory to prevent the re⁃establishment of imported malaria and consolidate the elimination achievements.  Related Articles | Metrics | Comments（0）

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Impact of drought on Oncomelania hupensis snails breeding in the Poyang Lake area HU Fei, LÜ Shangbiao, LI Yifeng, LI Zongguang, HE Tingting, XIE Jingzi, YUAN Min, LIN Dandan Chinese Journal of Schistosomiasis Control    2024, 36 (4): 370-375.   Abstract （194）      PDF（pc） （1714KB）（242）       Knowledge map    Save Objective　To examine the impact of arid climates on distribution of Oncomelania hupensis snails in the Poyang Lake area, so as to provide insights into precision control of O. hupensis snails in the Poyang Lake area. Methods　O. hupensis snails⁃infested grass islands in Hukou County, Lianxi District and Lushan City in the northern Poyang Lake area, and Jinxian County, Nanchang County and Poyang County in the southern Poyang Lake area were selected as the study areas, and the occurrence of frames with living snails and the mean density of living snails were captured from snail surveys in the study areas in spring and autumn each year from 2006 to 2023. Five years 2007, 2011, 2013, 2019 and 2022 were selected as drought years, and the mean daily water levels were collected at the Xingzi hydrological station in the drought years, normal flow year (2012) and flood year (2020). The numbers of days with water levels ranging from the lower elevation (11 m) to the upper elevation (16 m) for snail survival and the numbers of days with water levels of 11 m and below were collected in the Poyang Lake area, and the changes of snail indicators were compared in different grass islands in the Poyang Lake area before and after drought. Results　The numbers of days with water levels ranging from 11 to 16 m were 110, 88, 136 d and 125 d at the Xingzi hydrological station in four drought years 2007, 2011, 2013 and 2019, which were less than in the flow year and flood year, and the days with water levels of 11 m and below were 242, 277, 220 d and 198 d in four drought years 2007, 2011, 2013 and 2019, which were longer than in the flow year and flood year. A total of 416 snails⁃infested marshlands were surveyed in the Poyang Lake area from 2006 to 2021, and the survey marshlands accounted for 43.12% (307/712) and 46.98% (109/232) of total marshlands in the southern and northern Poyang Lake areas, respectively. The median occurrence of frames with living snail and mean density of living snail were 0.60% (interquartile range, 4.04%) and 0.010 1 snail/0.1 m2 (interquartile range, 0.076 1 snail/0.1 m2) in drought years, which were both lower than those [1.33% (5.19%) and 0.022 8 (0.098 9) snail/0.1 m2] in non⁃drought years ([χ2] = 42.170 and 44.911, both P values < 0.01). The proportion of grass islands with a continuous decline in snail indicators was higher in the southern Poyang Lake area than in the northern Poyang Lake area after the next year of drought (24.24% vs. 2.33%; [χ2] = 10.633, P < 0.01), and the proportion of grass islands with rebounding snail indicators was higher in the northern Poyang Lake area than in the southern Poyang Lake area (53.49% vs. 15.76%; [χ2] = 26.966, P < 0.01). A longitudinal analysis of snail indicators in marshlands with rebounding snail indicators after drought showed 1 to 5 years for return to pre⁃drought snail status, with a median of 2 (interquartile range, 1) years, and snail status was more likely to rebound if the occurrence of frames with living snails and the mean density of living snails were 2.11% and 0.025 5 snail/0.1 m2 and greater in snails⁃infested grass islands. Conclusions　Drought causes a remarkable decline in O. hupensis snail indicators in the Poyang Lake area, with a more remarkable impact in the southern Poyang Lake area, and 1 to 5 years are required for return to pre⁃drought snail status. Related Articles | Metrics | Comments（0）

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Distribution and seasonal fluctuation of visceral leishmaniasis vectors sandflies in Henan Province in 2023 HE Zhiquan, WANG Dan, KOU Yuanjing, YANG Chengyun, SUN Yiying, JI Penghui, JIANG Tiantian, LU Deling, QIAN Dan, ZHANG Hongwei, LIU Ying Chinese Journal of Schistosomiasis Control    2024, 36 (4): 346-351,398.   Abstract （194）      PDF（pc） （1042KB）（346）       Knowledge map    Save Objective　To investigate the geographical distribution and seasonal fluctuations of visceral leishmaniasis vectors sandflies in Henan Province in 2023, so as to provide insights into the prevention and control of visceral leishmaniasis vectors. Methods　A total of 23 counties (districts) were sampled from 18 cities of Henan Province from May to September, 2023 as sandfly surveillance sites, and sandflies were captured using human capture and light trapping methods. Following morphological identification, the changes in the sandfly density were calculated at different months and in different breeding habitats. Results 　 A total of 406 light traps were set at sandfly surveillance sites in Henan Province from May to September, 2023, and a total of 3 137 female sandlies were captured, with an average density of 7.73 sandlies/(light·night). A total of 1 494 Phlebotomus chinensis sandflies were captured, including 1 222 female sandflies, with an average density of 3.01 sandflies/(light·night), and the highest density of P. chinensis was found in Gongyi City [17.00 sandflies/(light·night)]. A total of 5 544 sandflies were captured using the human capture method, including 230 P. chinensis, and the density of P. chinensis appeared a unimodal distribution, with a peak in early July [5.81 sandflies/(light·night)]. Among different breeding habitats, the highest P. chinensis density was detected in pigpens [4.50 sandflies/(light·night)]. Conclusions　P. chinensis was predominantly distributed in hilly areas of northern and central⁃western Henan Province in 2023, and the sandfly density appeared a unimodal distribution. Intensified monitoring of visceral leishmaniasis vectors is recommended. Related Articles | Metrics | Comments（0）

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Cross⁃border joint prevention and control of tropical diseases in countries along the "Belt and Road" Initiative: a framework and roadmap QIAN Yingjun, DING Wei, LI Hongmei, WANG Duoquan, LÜ Shan, LI Shizhu, ZHOU Xiaonong Chinese Journal of Schistosomiasis Control    2025, 37 (1): 8-13.   Abstract （193）      PDF（pc） （1292KB）（491）       Knowledge map    Save Recently, there has been an increasing risk of importation of tropical diseases into China and the resultant retransmission in the country with the in⁃depth implementation of the "Belt and Road" Initiative, which poses a serious threat to the national public health security. To effectively respond to the cross⁃border transmission risk of tropical diseases and facilitate the process towards tropical disease control and elimination in China and the countries along the "Belt and Road" Initiative, this article analyzes the current status and governance risks of major imported tropical diseases, cross⁃border joint prevention and control polices implemented for tropical diseases and challenges in the establishment of the joint prevention and control system for tropical diseases in China, and discusses the establishment and implementation path of the joint prevention and control system for tropical diseases in countries along the "Belt and Road" Initiative. This path covers the establishment of cross⁃border cooperation mechanisms, research and development and pilot production of Chinese public health products, and implementation of key cross⁃border tropical disease prevention and control projects. The establishment of this system will further improve Chinese prevention and control capabilities for key cross⁃border tropical diseases, build a demonstrative prevention and control model for tropical diseases, and promote international technical exchanges and cooperation of tropical diseases.  Related Articles | Metrics | Comments（0）

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Factors affecting differentiation between Oncomelania hupensis and Tricula snails among schistosomiasis control professionals in Yunnan Province CUI Xiao, SONG Jing, LI Chunying, WANG Hongqiong, DU Chunhong, SHEN Meifen, YANG Zaogai, SHI Xinping, LI Shizhu, DONG Yi Chinese Journal of Schistosomiasis Control    2024, 36 (5): 514-520.   Abstract （191）      PDF（pc） （977KB）（200）       Knowledge map    Save Objective　To investigate the capability for distinguishing between the morphology of Oncomelania hupensis and Tricula snails and its influencing factors among schistosomiasis control professionals in Yunnan Province, so as to evaluate the interference of Tricula snails with O. hupensis surveys. Methods　O. hupensis and Tricula snails were sampled from 9 schistosomiasis⁃endemic counties (districts) in Yunnan Province. The capability for distinguishing between O. hupensis and Tricula snails was evaluated using online questionnaire surveys and field blind tests among schistosomiasis control professionals, and the proportions of correct judgment, misjudgment and missed judgment were calculated. Univariate and multivariate logistic regression models were created using the software SPSS 25.0, and factors affecting the proportion of correct judgments of O. hupensis snails were identified among schistosomiasis control professionals. Results　Questionnaire surveys and field blind tests showed that the overall proportions of correct judgments of O. hupensis snails were 56.77% (2 305/4 060) and 68.28% (1 556/2 279) among schistosomiasis control professionals in Yunnan Province, respectively. Univariate logistic regression analysis of online questionnaire surveys identified gender [odds ratio (OR) = 1.244, 95% confidential interval (CI): (1.073, 1.441), P < 0.05], professional title [OR = 0.628, 1.741, 95% CI: (0.453, 0.871), (1.109, 2.734), both P < 0.05], working duration [OR = 0.979, 95% CI: (0.971, 0.987), P < 0.05] and classification of schistosomiasis epidemics in endemic foci [OR = 1.410, 0.293, 0.523, 95% CI: (1.103, 1.804), (0.237, 0.361), (0.416, 0.657), both P < 0.05] as factors affecting the proportion of correct judgments of O. hupensis snails among schistosomiasis control professionals in Yunnan Province, and multivariate logistic regression analysis after adjustments showed that the proportion of O. hupensis snail misjudgments was 1.179 times higher among male schistosomiasis control professionals than among females [OR = 1.179, 95% CI: (1.006, 1.382), P < 0.05], and 1.474 times higher among schistosomiasis control professionals in schistosomiasis⁃elimination areas with snails than in areas without snails [OR = 1.474, 95% CI: (1.145, 1.898), P < 0.05], and the proportions of missed judgments of O. hupensis snails were 0.284 [OR = 0.284, 95% CI: (0.225, 0.359), P < 0.05] and 0.523 times [OR = 0.523, 95% CI: (0.412, 0.664), P < 0.05] higher among schistosomiasis control professionals in transmission⁃interruption areas with snails and schistosomiasis⁃elimination areas with snails than in schistosomiasis⁃elimination areas without snails. Univariate logistic regression analysis of field blind tests showed identified age [OR = 2.381, 95% CI: (1.677, 3.381), P < 0.05], professional title [OR = 1.688, 95% CI: (1.103, 2.582), P < 0.05］, working duration [OR = 0.970, 95% CI: (0.956, 0.984), P < 0.05] and classification of schistosomiasis epidemics in endemic foci [OR = 0.262, 0.593, 95% CI: (0.188, 0.364), (0.420, 0.837), both P < 0.05] as factors affecting the proportion of correct judgments of O. hupensis snails among schistosomiasis control professionals in Yunnan Province, and multivariate logistic regression analysis after adjustments showed the proportions of missed judgments of O. hupensis snails were 0.263 [OR = 0.263, 95% CI: (0.176, 0.394), P < 0.05] and 0.604 times [OR = 0.604, 95% CI: (0.416, 0.875), P < 0.05] higher among schistosomiasis control professionals in transmission⁃interruption areas with snails and schistosomiasis⁃elimination areas with snails than in schistosomiasis⁃elimination areas without snails. Conclusions　Schistosomiasis control professionals in Yunnan Province have a low accuracy rate for distinguishing between the morphology of O. hupensis and Tricula snails, and gender and classification of schistosomiasis epidemics in endemic foci are factors that affect their ability to distinguish. The presence of Tricula snails causes a high degree of interference with O. hupensis surveys in O. hupensis snail⁃infested areas of Yunnan Province. Reinforced training for distinguishing between O. hupensis and Tricula snails is required among schistosomiasis control professionals in Yunnan Province. Related Articles | Metrics | Comments（0）