Abstract: 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. 

Key words: Malaria, Reference laboratory, Diagnosis, Elimination, Shanghai Municipality

摘要： 目的　对2017—2022年上海市疟疾诊断参比实验室质量控制血片（质控血片）评价、病例复核以及检测能力评估结果进行分析，为提升疟疾消除后实验室诊断水平提供科学依据。方法　2017—2022年，上海市疟疾诊断参比实验室每季度按比例随机抽取阴性血片作为质控血片，对质控血片进行评分；对区级疾病预防控制（疾控）中心送检的疟疾病例血样采用镜检和多重PCR法进行复核；每年采用疟原虫镜检和核酸盲样考核方式对各区疟疾检测能力进行评估。对上述评分、复核结果和考核评估结果进行统计分析。结果　2017—2022年，区疾控中心共送检7 746张质控血片，平均分为（76.74 ± 14.34）分，合格率为86.65%（6 712/7 746）。送检复核血片387张，定性符合率和虫种符合率分别为96.38%（373/387）和95.06%（308/324），不同年份定性符合率（[χ2] = 2.57，P > 0.05）和虫种符合率（[χ2] = 1.04，P > 0.05）差异均无统计学意义。送检全血样本384份，区疾控中心的样本检测率为70.31%（270/384），市疾控中心对全部送检样本采用多重PCR法进行复核，定性符合率和虫种符合率分别为94.07%（254/270）和99.55%（223/224），不同年份定性符合率（[χ2] = 5.77，P > 0.05）和虫种符合率（[χ2] = 8.37，P > 0.05）差异均无统计学意义；区疾控中心阳性和阴性全血样本符合率分别为100.00%（224/224）和65.22%（30/46），差异有统计学意义（[χ2] = 82.82，P < 0.001）；恶性疟原虫、间日疟原虫、三日疟原虫和卵形疟原虫的符合率差异有统计学意义（[χ2] = 24.28，P < 0.001）。各区疾控中心及医疗机构共镜检盲样血片1 584张，定性正确率和虫种正确率分别为96.15%（1 523/1 584）和85.07%（1 003/1 179），不同年份的定性正确率（[χ2] = 20.98，P < 0.001）和虫种正确率（[χ2] = 70.77，P < 0.001）差异均有统计学意义。共检测320份疟疾病例核酸盲样，定性正确率和虫种正确率分别为99.38%（318/320）和100.00%（225/225），不同年份间定性正确率差异无统计学意义（[χ2] = 6.04，P > 0.05）。结论　2017—2022年上海市各区疟疾检测实验室的疟原虫血片制作、镜检和核酸检测工作仍存在不足，上海市疟疾诊断参比实验室应进一步发挥质量控制作用，以降低输入再传播风险，巩固消除成果。

关键词: 疟疾, 参比实验室, 诊断, 消除, 上海市