目的 了解2017—2022年山东省输入性疟疾流行病学特征，为进一步做好防止输入再传播工作提供科学依据。方法 从中国疾病预防控制信息系统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2017—2022年山东省输入性疟疾疫情、病例流行病学个案调查等资料，建立数据库，采用SPSS 26.0软件对疟疾病例分类、感染来源、流行病学特征、病例诊治情况等进行统计分析，率的比较采用χ²检验，时间间隔分布的比较用非参数检验，利用SaTScan v10.1软件对疟疾病例的空间聚集性进行扫描分析，利用GraphPad Prism 8.3.0软件进行绘图。结果 2017—2022年，山东省共报告输入性疟疾820例，均为境外输入性病例。新冠疫情前（2017—2019年）、新冠疫情期间（2020—2022年）分别报告670例、150例。820例均为实验室确诊病例，恶性疟、卵形疟、间日疟、三日疟病例分别占69.5%（570/820）、19.0%（156/820）、7.3%（60/820）和4.1%（34/820），无混合感染和未分型病例。感染来源地以非洲为主（95.9%，786/820）。全省16个市均有病例报告，济宁、烟台、威海、青岛和济南5个市共报告511例，占62.3%（511/820）。空间扫描分析发现7个病例聚集区，其中威海环翠、烟台牟平等13个县（市、区）为一类聚集区（相对危险度 = 3.98，P < 0.01）。 按报告地统计，全省共191例跨地区就诊病例，占23.3%（191/820）。全省18所疟疾救治定点医疗机构共报告本市就诊病例421例（55.3%，421/762）。患者发病到初诊、初诊到确诊时间间隔中位数分别为1、0 d。患者初诊单位为省级、市级、县级、县级以下医疗机构的分别占9.9%（81/820）、36.1%（296/820）、31.5%（258/820）和16.6%（136/820），疟疾诊断正确率分别为88.9%（72/81）、84.1%（249/296）、76.4%（197/258）和5.2%（7/136）；初诊单位为其他机构（疾控机构、检验检疫机构等）的占6.0%（49/820），诊断正确率为87.8%（43/49）。不同机构疟疾诊断正确率差异有统计学意义（χ² = 321.959，P < 0.01）。共报告重症疟疾74例，占9.0%（74/820），死亡病例5例。结论 2017—2022年，山东省输入性疟疾病例多、分布广，存在输入再传播的风险。

Objective To understand the epidemiological characteristics of imported malaria in Shandong Province and provide scientific basis for the prevention of re-transmission of imported malaria. Methods Data of the imported malaria epidemiological situation and case investigation in Shandong Province from 2017 to 2022 were collected from the Infectious Disease Reporting Information Management System and the Parasitic Disease Prevention and Control Information Management System of China Disease Prevention and Control Information System. A database for analysis was established. SPSS 26.0 software was use to analyze the case classification, source of infection, epidemiological characteristics, and the diagnosis and treatment records of the malaria cases. The χ² test was used to compare the rates, and the nonparametric test was used to compare the time interval distribution. The spatial clustering of malaria cases was analyzed by scanning with SaTScan v10.1 software. Figures were generated using GraphPad Prism 8.3.0 software. Results From 2017 to 2022, a total of 820 imported malaria cases were reported in Shandong Province, all of which were imported from abroad. A total of 670 cases were reported before the corona virus disease 2019 （COVID-19） pandemic and 150 cases during the COVID-19 pandemic. All the 820 cases were laboratory-diagnosed. falciparum malaria, ovale malaria,vivax malaria and malariae malaria accounted for 69.5% (570/820), 19.0% (156/820), 7.3% (60/820) and 4.1% (34/820), respectively. There were no mixed infections and unclassified cases. The main source of the infections was Africa (95.9%, 786/820). All 16 cities in Shandong Province had cases reported, while 511 cases were reported in five cities, including Jining, Yantai, Weihai, Qingdao and Jinan, accounting for 62.3% (511/820). Spatial scanning analysis found 7 case clusters, among which 13 counties, such as Huancui in Weihai and Muping in Yantai were the primary clusters (relative risk = 3.98, P < 0.01). According to the city where the case was reported, 191 cases had been treated in a different region within the province, accounting for 23.3% (191/820). A total of 421 local cases (55.3%, 421/762) were reported by 18 medical facilities designated for malaria treatment in the province. The median time interval from onset of symptoms to initial diagnosis and from initial diagnosis to final diagnosis was 1 and 0 days, respectively. The proportion of patients who were initially diagnosed in the provincial, municipal, county, and below-county medical facilities was 9.9% (81/820), 36.1% (296/820), 31.5% (258/820) and 16.6% (136/820), respectively. The malaria diagnosis accuracy was 88.9% (72/81), 84.1% (249/296), 76.4% (197/258) and 5.2% (7/136), respectively, with 6.0% (49/820) of the patients initially diagnosed in other institutions, such as centres for disease control, inspection and quarantine organizations, and the malaria diagnosis accuracy was 87.8% (43/49). There was a significant difference in the malaria diagnosis accuracy in different institutions (χ² = 321.959, P < 0.01). A total of 74 severe malaria cases were reported, accounting for 9.0% (74/820), and 5 cases decesed. Conclusion There are high number of imported malaria cases in Shandong Province, which are widely distributed. The risk of re-transmission exists.