Background Enhancing regional collaboration in malaria prevention and control is a pivotal strategy for malaria control and elimination in China. The objective of this study is to examine the regional heterogeneity of malaria healthcare-seeking behaviors and diagnosis across various regions in China from 2017 to 2022. Methods Individual case data from national malaria surveillance databases were utilized. An analysis was conducted to discern the regional variations in the healthcare-seeking behaviors and diagnosis among regions. Results From 2017 to 2022, a total of 10943 malaria cases were reported in China, predominantly imported cases (10929), with significant variations in the distribution of different Plasmodium species among regions (P < 0.001) and annually (P < 0.001). There was a notable lack of timeliness in healthcare seeking (56.1%) and case confirmation (67.3%) with substantial regional disparities (P < 0.001). These delays predominantly occurred in county and prefectural-level medical institutions (P < 0.001), where misidentification of Plasmodium species was also prevalent (P < 0.001). Furthermore, an initial diagnosis of malaria was observed in 76.6% of cases ( P < 0.001), yet 87.8% of malaria cases were ultimately confirmed correctly (P < 0.001). Notably, P. ovale (21.0%) and P. malariae (10.8%) were easily misidentified as P. vivax (P < 0.001). Conclusion The development of regional-specific interventions is essential to raise public awareness regarding malaria-related knowledge and to enhance the vigilance of health workers and their capacity of malaria testing. This will strengthen the nation’s malaria surveillance and response system. Concurrently, fostering technological innovations for the rapid and precise identification of Plasmodium species, along with effective coordination of cross-regional mechanisms, is imperative to prevent re-establishment of malaria transmission in China.

There has been a significant reduction in malaria morbidity and mortality worldwide from 2000 to 2019. However, the incidence and mortality increased again in 2020 due to the disruption to services during the COVID-19 pandemic. Surveillance to reduce the burden of malaria, eliminate the disease and prevent its retransmission is, therefore, crucial. The 1-3-7 approach proposed by China has played an important role in eliminating malaria, which has been internationally popularized and adopted in some countries to help eliminate malaria. This review summarizes the experience and lessons of 1-3-7 approach in China and its application in other malaria-endemic countries, so as to provide references for its role in eliminating malaria and preventing retransmission. This approach needs to be tailored and adapted according to the region condition, considering the completion, timeliness and limitation of case-based reactive surveillance and response. It is very important to popularize malaria knowledge, train staff, improve the capacity of health centres and monitor high-risk groups to improve the performance in eliminating settings. After all, remaining vigilance in detecting malaria cases and optimizing surveillance and response systems are critical to achieving and sustaining malaria elimination.

In 2017, China achieved the target of zero indigenous malaria case for the first time, and has been certified as malaria free by World Health Organization in 2021. To further summarize the historical achievements and technical experiences of the elimination program, a project on the Roadmap Analysis and Verification for Malaria Elimination in China was carried out. Results of the project were compiled and published as the Atlas of Malaria Transmission in China (The Atlas). The Atlas using modern digital information technologies, has been supported by various data from 24 malaria endemic provinces of China since 1950, to assess the changes in malaria epidemic patterns from 1950 to 2019 at national and provincial levels. The Atlas is designed as two volumes, including a total of 1850 thematic maps and more than 130 charts, consisting of introductory maps, thematic maps of malaria epidemic and control at national and provincial levels. It objectively and directly shows the epidemic history, evolution process, and great achievements of the national malaria control and elimination program in China. The Atlas has important reference value for summing up historical experience in the national malaria elimination program of China, and malaria control and elimination in other endemic countries in the world.

OBJECTIVE:No indigenous malaria cases have been reported since 2017 in China, but a large number of imported cases are still reported every year, including those from the land bordering countries. To characterize their epidemiological profiles will provide evidence for the development of appropriate strategies to effectively address the challenges of border malaria in the post-elimination phase.METHODS:Individual-level data of imported malaria cases from the land bordering countries were collected from 2017 to 2021 in China via the web-based surveillance systems, and analyzed by SPSS, ArcGIS and WPS software, to explore their epidemiological profiles.RESULTS:A total of 1170 malaria cases imported into China from six of the fourteen land bordering countries were reported between 2017 and 2021 with a decline trend. Overall, cases were widely distributed in 31-97 counties from 11 to 21 provinces but mainly in Yunnan. Moreover, these imported cases were mainly infected with P. vivax (94.8%), and a total of 68 recurrent cases were reported in 6-14 counties from 4 to 8 provinces. In addition, nearly 57.1% of the total reported cases could seek healthcare within 2 days of getting sick, and 71.3% of the reported cases could be confirmed as malaria on the day they sought medical care.CONCLUSIONS:China still needs to attach great importance to the risk and challenge of the imported malaria from bordering countries particularly from Myanmar in preventing reestablishment of malaria transmission in the post-elimination phase. It is necessary not only to strengthen collaboration and cooperation with the bordering countries, but also coordinate multiple departments at home to improve malaria surveillance and response system and prevent the reestablishment of malaria transmission in China.

Background Plasmodium malariae was always neglected compared with P. falciparum and P. vivax . In the present study, we aimed to describe the epidemiology of reported cases infected with P. malariae in the past decade to raise awareness of the potential threat of this malaria parasite in China. Methods Individual data of malaria cases infected with P. malariae reported in China in the past decade were collected via the China Information System for Disease Control and Prevention and Parasitic Diseases Information Reporting Management System, to explore their epidemiological characteristics. Pearson Chi-square tests or Fisher’s Exact Test was used in the statistical analysis. Results From 2013 to 2022, a total of 581 P. malariae cases were reported in China, and mainly concentrated in 20–59 years old group ( P < 0.001), and there was no significant trend in the number of cases reported per month. Moreover, four kinds of P. malariae cases were classified, including 567 imported cases from 41 countries in 8 regions and distributed in 27 provinces (autonomous regions, municipalities) in China, six indigenous cases in a small outbreak in Hainan, seven recurrent cases in Guangdong and Shanghai, and one induced case in Shanghai, respectively. In addition, only 379 cases (65.2%) were diagnosed as malaria on the first visit ( P < 0.001), and 413 cases (71.1%) were further confirmed as P. malariae cases ( P = 0.002). Meanwhile, most cases sought healthcare first in the health facilities at the county and prefectural levels, but only 76.7% (161/210) and 73.7% (146/198) cases were diagnosed as malaria, and the accuracy of confirmed diagnosis as malaria cases infected with P. malariae was only 77.2% (156/202) and 69.9% (167/239) in these health facilities respectively. Conclusions Even though malaria cases infected with P. malariae didn’t account for a high proportion of reported malaria cases nationwide, the threat posed by widely distributed imported cases, a small number of indigenous cases, recurrent cases and induced case cannot be ignored in China. Therefore, it is necessary to raise awareness and improve the surveillance and response to the non-falciparum species such as P. malariae , and prevent the reestablishment of malaria transmission after elimination. Graphical Abstract

目的 了解山东省2012-2021年疟疾疫情及新型冠状病毒肺炎流行前后疟疾监测响应情况,为制定输入性疟疾防控措施防止输入再传播提供依据.方法 收集传染病报告信息管理系统2012-2021年山东省疟疾疫情数据及寄生虫病防治信息系统中病例流行病学个案调查资料,分析疟疾病例报告数量、感染来源、流行病学特征、病例诊治、"1-3-7"指标完成情况,并对新冠肺炎流行前5年及流行期间的相关指标进行统计分析.结果 2012-2021年山东省共报告疟疾病例1 619例,1 605例为实验室确诊病例,其中恶性疟1 208例,占75.26％;间日疟144例,占8.97％;卵形疟204例,占12.71％;三日疟49例,占3.05％.除2例云南输入病例和1例输血感染病例外,其余1 616例均为境外输入病例,其中非洲38个国家输入1 551例,占95.98％,主要感染来源国家分别为赤道几内亚、安哥拉、尼日利亚、刚果民主共和国、几内亚.2013-2021年,恶性疟构成比呈下降趋势(Z=33.438,P＜0.01),卵形疟构成比呈上升趋势(Z=54.025,P＜0.01).新冠肺炎疫情前后,年平均报告疟疾病例数由227.4例下降至54例,病例构成比差异有统计学意义(x2=30.124,P＜0.01);疫情期间非洲国家输入病例构成比显著减少(x2=14.093,P＜0.01).新冠肺炎疫情期间,报告疟疾病例的发病-初诊时间间隔中位数为1 d,平均数为(1.64±2.07)d,新冠肺炎疫情前中位数1 d,平均数(2.96±6.00)d,差异有统计学意义(Z=-2.323,P＜0.05);初诊-确诊时间间隔中位数0.5 d,平均数(1.65±3.06)d,新冠肺炎疫情前中位数0 d,平均数(2.05±5.15)d,差异无统计学意义(Z=0.354,P＞0.05);初次就诊被诊断为疟疾正确率为75.00％,新冠肺炎疫情前为68.34％,差异无统计学意义(x2=2.044,P＞0.05);重症病例构成比为8.33％,新冠肺炎疫情前为9.76％,差异无统计学意义(x2=0.231,P＞0.05);3 d内流行病学个案调查完成率99.07％,新冠肺炎疫情前为97.26％,差异无统计学意义(x2=1.291,P＞0.05);7 d内疫点处置完成率为99.06％,新冠肺炎疫情前为94.65％,差异有统计学意义(x2=3.980,P＜0.05).结论 新冠肺炎流行期间,山东省输入性疟疾防控措施正常落实,但境外输入性疟疾防控仍面临很多挑战.应继续加强宣传教育和技能培训,提高患者及时就诊意识、基层医疗机构疟疾诊治意识及重症病例救治能力,防止疟疾输入再传播.

In 2017, China achieved the target of zero indigenous malaria case for the first time, and has been certified as malaria free by World Health Organization in 2021. To further summarize the historical achievements and technical experiences of the elimination program, a project on the Roadmap Analysis and Verification for Malaria Elimination in China was carried out. Results of the project were compiled and published as the Atlas of Malaria Transmission in China (The Atlas). The Atlas using modern digital information technologies, has been supported by various data from 24 malaria endemic provinces of China since 1950, to assess the changes in malaria epidemic patterns from 1950 to 2019 at national and provincial levels. The Atlas is designed as two volumes, including a total of 1850 thematic maps and more than 130 charts, consisting of introductory maps, thematic maps of malaria epidemic and control at national and provincial levels. It objectively and directly shows the epidemic history, evolution process, and great achievements of the national malaria control and elimination program in China. The Atlas has important reference value for summing up historical experience in the national malaria elimination program of China, and malaria control and elimination in other endemic countries in the world.

Background: Artemisinin-based combination therapy (ACT) has been recommended as the first-line treatment by the World Health Organization to treat uncomplicated Plasmodium falciparum malaria. However, the emergence and spread of P. falciparum resistant to artemisinins and their partner drugs is a significant risk for the global effort to reduce disease burden facing the world. Currently, dihydroartemisinin-piperaquine (DHA-PPQ) is the most common drug used to treat P. falciparum, but little evidence about the resistance status targeting DHA (ACT drug) and its partner drug (PPQ) has been reported in Shandong Province, China. Methods: A retrospective study was conducted to explore the prevalence and spatial distribution of Pfk13 and Pfcrt polymorphisms (sites of 72-76, and 93-356) among imported P. falciparum isolates between years 2015-2019 in Shandong Province in eastern China. Individual epidemiological information was collected from a web-based reporting system were reviewed and analysed. Results: A total of 425 P. falciparum blood samples in 2015-2019 were included and 7.3% (31/425) carried Pfk13 mutations. Out of the isolates that carried Pfk13 mutations, 54.8% (17/31) were nonsynonymous polymorphisms. The mutant alleles A578S, Q613H, C469C, and S549S in Pfk13 were the more frequently detected allele, the mutation rate was the same as 9.7% (3/31). Another allele Pfk13 C580Y, closely associated with artemisinin (ART) resistance, was found as 3.2% (2/31), which was found in Cambodia. A total of 14 mutant isolates were identified in Western Africa countries (45.2%, 14/31). For the Pfcrt gene, the mutation rate was 18.1% (77/425). T76T356 and T-76 were more frequent in all 13 different haplotypes with 26.0% (20/77) and 23.4% (18/77). The CVIET and CVIKT mutant at loci 72-76 have exhibited a prevalence of 19.5% (15/77) and 3.9% (3/77), respectively. The CVIET was mainly observed in samples from Congo (26.7%, 4/15) and Mozambique (26.7%, 4/15). No mutations were found at loci 97, 101 and 145. For polymorphisms at locus 356, a total of 24 isolates were identified and mainly from Congo (29.2%, 7/24). Conclusion: These findings indicate a low prevalence of Pfk13 in the African isolates. However, the emergence and increase in the new alleles Pfcrt I356T, reveals a potential risk of drug pressure in PPQ among migrant workers returned from Africa. Therefore, continuous molecular surveillance of Pfcrt mutations and in vitro susceptibility tests related to PPQ are necessary.

目的 调查《疟疾的诊断》(WS259-2015)标准在各级疾病预防控制和医疗机构的知晓、掌握和现场应用情况,为进一步完善标准的内容和指标、精准化开展标准宣贯和强化标准实施提供科学依据.方法 根据全国疟疾疫情数据资料将全国流行省份分为高、中、低三层,每层选取一个省份,对不同层级工作人员开展问卷调查后,赴现场进行访谈;同时搜集国家正式发布且正在使用的与疟疾消除和诊断相关的文件.结果 回收调查问卷共320份,包括有效问卷301份,有效率达94.06％.有效问卷结果显示,94.35％(284/301)的疟疾防治工作者知晓该标准,获取途径以主动查阅为主.标准内容指标总体掌握率为72.09％(217/301),"疟疾诊断类型"和"疟疾临床表现"的掌握率较低,分别为39.53％(119/301)和36.55％(110/301).标准一致性调查中,现行疟疾工作方案、网报系统与标准中临床表现、诊断类型等内容不完全一致.适用性评价中,92.36％(278/301)的被调查者认为该标准完全适用,仅6.64％(20/301)认为需要修订.回收问卷中对于该标准实施的建议共67条.结论 各级疾控与医疗机构疟疾防治工作者对新版诊断标准掌握率偏低,理解有一定偏差,亟需加大培训宣传力度,开展标准解读.有必要在标准实施的不同阶段开展标准的跟踪评价,发挥标准的指导作用.

Introduction:Qualified microscopy competency is a key indicator for certification of malaria elimination. To better prepare the country certification and identify the priorities that need improvement to prevent malaria reestablishment, microscopy competency at different levels were assessed in subnational verification of malaria elimination in China. Methodology. Microscopist representatives from centers for disease control and prevention (CDC)/institutes of parasitic diseases (IPD) and medical institutes for malaria diagnosis at the provincial and county levels in the subnational verification were analyzed. Specifically, five provincial microscopist representatives and ten county-level representatives were assessed in each of previously endemic provinces on qualitative identification (Plasmodium positive or negative) and Plasmodium species identification using standard slides from the National Malaria Diagnosis Reference Laboratory.Results:A total of 100 provincial-level representatives (60 from 42 CDCs/IPDs and 40 from 34 medical institutes) and 200 county-level representatives (61 from 41 CDCs and 139 from 118 medical institutes) were included. The qualitative accuracy was higher than 90% each (P = 0.137), but slides with low parasite density were easy to be misdiagnosed as negative. Furthermore, the accuracy of species identification was 80.0% and 83.6% in medical institutes and centers for disease control and prevention (CDCs) at the provincial level (P = 0.407) with relatively high misdiagnosis of P. vivax as P. ovale in the latter (16.2%) and 82.0% and 85.0% in medical institutes and CDCs at the county level (P = 0.330) for the identification of P. falciparum and non-P. falciparum with higher false-negative in medical institutions (P < 0.001).Conclusions:In conclusion, competent microscopy in subnational verification supported the quality in eliminating malaria in China, while the accurate identification of malaria parasites, especially slides with low parasite density still need to be improved through continuous diagnostic platform construction, continuous technological innovation, and targeted training to prevent reestablishment of malaria transmission.

The dihydrofolate reductase (dhfr) and dihydropteroate synthetase (dhps) genes of Plasmodium vivax, as antifolate resistance-associated genes were used for drug resistance surveillance. A total of 375 P. vivax isolates collected from different geographical locations in China in 2009–2019 were used to sequence Pvdhfr and Pvdhps. The majority of the isolates harbored a mutant type allele for Pvdhfr (94.5%) and Pvdhps (68.2%). The most predominant point mutations were S117T/N (77.7%) in Pvdhfr and A383G (66.8%) in Pvdhps. Amino acid changes were identified at nine residues in Pvdhfr. A quadruple-mutant haplotype at 57, 58, 61, and 117 was the most frequent (57.4%) among 16 distinct Pvdhfr haplotypes. Mutations in Pvdhps were detected at six codons, and the double-mutant A383G/A553G was the most prevalent (39.3%). Pvdhfr exhibited a higher mutation prevalence and greater diversity than Pvdhps in China. Most isolates from Yunnan carried multiple mutant haplotypes, while the majority of samples from temperate regions and Hainan Island harbored the wild type or single mutant type. This study indicated that the antifolate resistance levels of P. vivax parasites were different across China and molecular markers could be used to rapidly monitor drug resistance. Results provided evidence for updating national drug policy and treatment guidelines.

Malaria remains a global health challenge, although an increasing number of countries will enter pre-elimination and elimination stages. The prompt and precise diagnosis of symptomatic and asymptomatic carriers of Plasmodium parasites is the key aspect of malaria elimination. Since the launch of the China Malaria Elimination Action Plan in 2010, China has formulated clear goals for malaria diagnosis and has established a network of malaria diagnostic laboratories within medical and health institutions at all levels. Various external quality assessments were implemented, and a national malaria diagnosis reference laboratory network was established to strengthen the quality assurance in malaria diagnosis. Notably, no indigenous malaria cases have been reported since 2017, but the risk of re-establishment of malaria transmission cannot be ignored. This review summarizes the lessons about malaria diagnosis in the elimination phase, primarily including the establishments of laboratory networks and quality control in China, to better improve malaria diagnosis and maintain a malaria-free status. A reference is also provided for countries experiencing malaria elimination.

On 30 June 2021, China was certified malaria-free by the World Health Organization. In this study, the evolution, performance, outcomes, and impact of China’s adaptive strategy and approach for malaria elimination from 2011 to 2020 were analysed using 10-year data. The strategy and approach focused on timely detection and rapid responses to individual cases and foci. Indigenous cases declined from 1,308 in 2011 to 36 in 2015, and the last one was reported from Yunnan Province in April 2016, although thousands of imported cases still occur annually. The “1–3–7” approach was implemented successfully between 2013 and 2020, with 100% of cases reported within 24 h, 94.5% of cases investigated within three days of case reporting, and 93.4% of foci responses performed within seven days. Additionally, 81.6% of patients attended the first healthcare visit within 1–3 days of onset and 58.4% were diagnosed as malaria within three days of onset, in 2017–2020. The adaptive strategy and approach, along with their universal implementation, are most critical in malaria elimination. In addition to strengthening surveillance on drug resistance and vectors and border malaria collaboration, a further adapted three-step strategy and the corresponding “3–3–7” model are recommended to address the risks of re-transmission and death by imported cases after elimination. China’s successful practice and lessons learnt through long-term efforts provide a reference for countries moving towards elimination.

Malaria was once one of the most severe public health problems in China. However, after 70 years of integrated interventions, substantial progress has been made, and remarkable milestones have been met in malaria elimination in China. On June 30th, 2021, China was officially certified as a malaria-free country by the World Health Organization. This paper highlights the achievements of, and lessons learned from the malaria elimination programme.

目的 分析2010-2019年全国输入性疟疾疫情特征,为各地消除疟疾后防止输入再传播工作提供依据.方法 利用中国疾病预防控制中心疾病监测信息报告管理系统(网络直报系统)和寄生虫病监测信息报告管理系统(寄生虫病专报系统),收集2010-2019年全国输入性疟疾疫情数据资料,建立数据库进行统计分析.结果 2010-2019年,全国各省均有输入性疟疾病例分布,共报告29 248例(年均2 925例),其中临床诊断疟疾病例767例(2.62％)、间日疟7 388例(25.26％)、恶性疟18 032例(61.65％)、三日疟524例(1.79％)、卵形疟2 049例(7.01％)、诺氏疟2例(0.01％)、混合感染370例(1.27％)和未分型病例116例(0.40％).病例主要输自缅甸(2 750例,9.40％)、加纳(2 606例,8.91％)和尼日利亚(2 127例,7.27％)等国;主要分布在云南(5 794例,19.81％)、广西(3 130例,10.70％)和江苏(2 917例,9.97％)等省份.病例主要在6月(4 141 例,14.16％)报告.人群分布中以男性为主(27 454例,93.87％).死亡病例181例,均为恶性疟.2010-2019年病例发病到诊断时间间隔各年差异无统计学意义(P＞0.05).病例主要在县级机构诊断(8 680例,39.75％)和报告(8 783例,40.22％),但呈逐年下降趋势,地市级机构呈现明显上升趋势;主要在临床医疗机构诊断(15 730例,72.03％)和报告(16 536例,75.72％),且逐年上升,疾控机构比例在逐年下降.结论 针对消除后输入性疟疾的重大威胁,应进一步加强部门间联防联控,强化监测,及时发现和规范治疗输入病例,开展传播风险调查和评估,对风险疫点和重点人群进行及时响应和处置,通过以"强化联防、及时发现、快速处置"为核心的综合性策略和措施防止疟疾输入再传播,巩固消除疟疾成果.

Vector control interventions including long-lasting insecticidal nets and indoor residual spraying are important for malaria control and elimination. And effectiveness of these interventions depends entirely on the high level of susceptibility of malaria vectors to insecticides. However, the insecticide resistance in majority of mosquito vector species across African countries is a serious threat to the success of vector control efforts with the extensive use of insecticides, while no data on insecticide resistance was reported from Sierra Leone in the past decade. In the present study, the polymerase chain reaction was applied for the identification of species of 757 dry adult female Anopheles gambiae mosquitoes reared from larvae collected from four districts in Sierra Leone during May and June 2018. And the mutations of kdr , rdl , ace-1 genes in An. gambiae were detected using SNaPshot and sequencing. As a result, one sample from Western Area Rural district belonged to Anopheles melas , and 748 An. gambiae were identified. Furthermore, the rdl mutations, kdr west mutations and ace-1 mutation were found. The overall frequency was 35.7%, 0.3%, 97.6% and 4.5% in A296G rdl , A296S rdl , kdrW and ace-1 , respectively. The frequencies of A296G rdl mutation ( P < 0.001), kdrW mutation ( P = 0.001) and ace-1 mutation ( P < 0.001) were unevenly distributed in four districts, respectively, while no statistical significance was found in A296S rdl mutation ( P = 0.868). In addition, multiple resistance patterns were also found. In conclusion, multiple mutations involved in insecticide resistance in An. gambiae populations in Sierra Leone were detected in the kdrW , A296G rdl and ace-1 alleles in the present study. It is necessary to monitor vector susceptibility levels to insecticides used in this country, and update the insecticide resistance monitoring and management strategy.

目的 比较HemoCue@hb301仪(以下简称HemoCue仪)和Sysmex全自动血液分析仪测定血红蛋白水平的相关性和一致性,评估HemoCue仪检测血红蛋白(hemoglobin,Hb)应用于现场人群调查的适用性.方法 用HemoCue仪和Sysmex全自动血液分析仪对相同的100例人体全血标本进行检测,比较两者测定的Hb值的相关性和一致性.采用随机数字法选取45份标本并分成3组,每份标本再平均分成4份,分别在常温,-4℃与-20℃条件下储存不同时间(12,24,36和48h)后用HemoCue仪测定Hb含量,比较不同储存温度和时间对检测结果 的影响.结果 两种方法 的检测结果 具有较好的相关性,r=0.995,但HemoCue仪测定值较Sysmex高,两者差异有统计学意义(t=11.471,P<0.001).两种方法 的一致性较好,LoA为(1.8,14.4).HemoCue仪诊断贫血的灵敏度为58.62％,特异度为100％,阳性预测值为100％,阴性预测值为85.54％.三次重复测量的组间相关系数ICC为0.996,95％CI 0.993～0.997.常温下与-20℃下分别储存0～48 h后,Hb值略有升高趋势.4℃组储存条件下Hb含量相对稳定.结论 HemoCue仪在检测Hb含量有较好的一致性和稳定性,适合于现场应用.

Introduction: Antimalarial drug resistance, especially artemisinin resistance, has been a global threat to reduce morbidity and mortality and to eliminate malaria. Antimalarial drug resistance surveillance could provide evidence for the efficacy of a national drug policy for treatment of all reported malaria cases. Methods: The therapeutic efficacy of dihydroartemisinin-piperaquine (DHA-PPQ) and chloroquine (CQ) for the treatment of uncomplicated Plasmodium falciparum and Plasmodium vivax infection, respectively, was evaluated by enrolling patients between 2016 and 2020. Surveillance of molecular markers involved collecting blood samples by passive or active detection and amplifying the drug resistance genes Pfcrt, Pfmdr1, Pfdhfr, Pfdhps, and PfK13 . Results: DHA-PPQ and CQ were effective for the treatment of P. falciparum and P. vivax infections, with cure rates > 90% and 100%, respectively. Among the 2,492 samples, the Pfcrt wild-type CVMNK was the most frequent haplotype (70.1%, 1,747/2,492), while 19.4% (484/2,492) displayed the triple mutant haplotype CVIET. In total of 228 isolates with sequencing in Pfdhfr and Pfdhps, high mutant prevalence of 98.7% and 95.2% were detected, respectively. A total of 54 non-synonymous mutations in the PfK13 propeller domain were confirmed with a prevalence of 3.5% (87/2,483), and the most common mutation was A5785, with a proportion of 16.1% (14/87), followed by Q613E (6.9%, 6/87). Conclusion and Implications for Public Health Practice: DHA-PPQ and CQ, the first line drugs for P. falciparum and P. vivax treatment, showed efficacy in China. Molecular markers showed high levels of polymorphism and resistance, which revealed an early warning of drug resistance in imported cases.

目的 分析中国消除疟疾监测响应系统的实施和工作成效,为消除后防止疟疾输入再传播工作提供科学依据.方法 系统收集整理消除疟疾监测响应相关的方案和活动记录,以及基于国家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2011-2020年全国疟疾病例个案信息和监测指标数据,使用SPSS 25.0和GraphPad Prism 8.4.3软件进行统计分析.结果 2011-2020年,全国共报告疟疾病例30278例,中国籍28448例(93.96％).本地原发感染病例1732例(5.72％),为2011-2016年报告;境外输入性病例28173例(93.05％);输血感染病例9例(0.03％);长潜伏期三日疟5例(0.02％);输入继发间日疟4例(0.01％);来源不明病例355例(1.17％),为2011-2013年报告.病例以恶性疟(17960例,59.32％)为主;主要集中在云南(5415例,17.88％)、广西(3193例,10.55％)、江苏(2797例,9.24％)等省(自治区);全年均有病例报告,主要集中在5-7月(9689例,32.00％).输入性病例主要来自缅甸(4856例,17.24％)、加纳(2957例,10.50％)、尼日利亚(2693例,9.56％)等国.被动监测、人群主动病例侦查和线索追踪病例侦查的血检阳性率分别为0.76％(28452/37500291)、0.03％ (35/1215309)和0.30％ (32/105384).2013-2020年,病例诊断后1日内报告率为100％ (23114/23114),报告后3日内流行病学个案调查率为94.49％ (21840/23114),7日内疫点调查和处置率为93.30％ (20294/21751),病例发病到初诊以及初诊到确诊间隔时间中位数均为1d(四分位距:0～3d).中华按蚊分布广泛,且普遍对溴氰菊酯产生抗性.体内疗效观察双氢青蒿素哌喹片对恶性疟、氯伯喹对间日疟的治愈率分别为92.31％ (36/39)和100％ (21/21).结论 建设敏感有效的监测响应系统是中国消除疟疾的成功经验,在消除疟疾后应继续把监测响应作为核心措施,积极开展部门合作,加强能力建设,防止输入再传播,巩固消除成果.