Abstract: Objective　To analyze the epidemiological characteristics of imported cases with Plasmodium ovale infections in Jiangsu Province from 2012 to 2020, so as to provide insights into the development of the imported malaria control strategy in the province. Methods　All data pertaining to cases with definitive diagnosis of P. ovale malaria in Jiangsu Province from 2012 to 2020 were captured from the National Notifiable Disease Report System and the Information Management System for Parasitic Disease Control in China, including the date of going abroad and returning to China, time of malaria infections overseas, date of malaria onset, initial diagnosis and definitive diagnosis. All data pertaining to epidemic status were descriptively analyzed. Results　A total of 347 cases of P. ovale malaria were reported in Jiangsu Province from 2012 to 2020, with the highest number seen in 2015 (71 cases). All cases were laboratory⁃confirmed overseas imported malaria cases, accounting for 14.32% of all reported malaria cases in Jiangsu Province during the period from 2012 to 2020. The 5 cities with the highest number of imported P. ovale malaria cases included Lianyungang City (53 cases, 15.27%), Nantong City (44 cases, 12.68%), Huai’an (44 cases, 12.68%), Taizhou City (44 cases, 12.68%) and Yangzhou City (36 cases, 10.37%). The highest number of imported P. ovale malaria cases was reported in October (39 cases, 11.24%), and the lowest number was seen in December (21 cases, 6.05%). P. ovale infections mainly occurred in were Equatorial Guinea (97 cases, 37.95%), Angola (60 cases, 17.29%) and Nigeria (40 cases, 11.53%). The median duration between returning to China and malaria onset was 64 (144) days, and 7.49% (26/347) of all cases developed malaria one year after returning to China. The initial diagnosis of P. ovale malaria was mainly made at county⁃level medical institutions (117 cases, 33.72%), and the definitive diagnosis was mainly made at city⁃level medical institutions (122 cases, 35.16%). The correct rate of initial diagnosis of P. ovale malaria increased from 0 in 2012 to 78.26% in 2020, appearing a tendency towards a rise year by year ([χ2] = 50.90, P < 0.01). Conclusions　Imported P. ovale malaria cases were reported in Jiangsu Province each year from 2012 to 2020, and P. ovale infections predominantly occurred in Africa. Initial and definitive diagnoses of P. ovale malaria were mainly made at city⁃ and county⁃level medical institutions. Training on the detection ability of malaria parasites is recommended among grassroots microscopists to improve the diagnostic ability of P. ovale malaria, and consolidate the achievements of malaria elimination in Jiangsu Province.

Key words: Plasmodium ovale malaria, Epidemiological characteristic, Imported case, Jiangsu Province

摘要： 目的　分析2012—2020年江苏省输入性卵形疟病例流行病学特征，为该省制定输入性疟疾防控策略提供科学依据。方法　在传染病报告信息管理系统和寄生虫病防治信息管理系统中，收集2012—2020年江苏省卵形疟确诊病例相关信息，包括出国、回国时间，在国外患病次数，发病、初诊和确诊时间，初诊和确诊单位等资料，进行描述性统计分析。结果　2012—2020年江苏省累计报告卵形疟病例347例，其中2015年报告例数最多（71例）。347例卵形疟病例均为实验室确诊的境外输入性病例，占该阶段江苏省报告疟疾病例总数的14.32%。全省卵形疟报告例数居前5位的地级市依次为连云港市（53例，占15.27%）、南通市（44例，占12.68%）、淮安市（44例，占12.68%）、泰州市（44例，占12.68%）和扬州市（36例，占10.37%）。报告病例数以10月最多，达39例（占11.24%）；12月最少，为21例（占6.05%）。卵形疟病例境外感染来源地主要为赤道几内亚（97例，占37.95%）、安哥拉（60例，占17.29%）、尼日利亚（40例，占11.53%）。卵形疟病例从回国到发病中位时间为64（144） d，其中7.49%（26/347）的病例回国1年后发病。病例初诊单位主要集中在县级医疗机构（117例，占33.72%），确诊单位主要集中在地市级医疗机构（122例，占35.16%）。2012—2020年江苏省卵形疟病例初诊正确率从2012年的0提升到2020年的78.26%，呈逐年上升趋势（[χ2] = 50.90，P＜0.01）。结论　2012—2020年江苏省每年均有输入性卵形疟病例报告，感染来源地主要为非洲，初诊和确诊单位主要集中在地市级和县级等基层医疗机构。今后应重点开展基层镜检人员疟原虫检测能力培训，以提高卵形疟诊断能力、巩固消除疟疾成果。

关键词: 卵形疟, 流行病学特征, 输入性病例, 江苏省