Ovale Malaria Cases Research Articles

Epidemiological characteristics and diagnosis of imported Plasmodium malariae and Plasmodium ovale malaria cases in five provinces of China from 2014 to 2021

To investigate the epidemiological characteristics and diagnosis of imported Plasmodium malariae and P. ovale malaria cases in Anhui Province, Hubei Province, Zhejiang Province, Guangxi Zhuang Autonomous Region and Henan Province from 2014 to 2021, so as to provide insights into malaria control in these five provinces. All data pertaining to malaria cases reported in five provinces of China were captured from Chinese Disease Control and Prevention Information System from 2014 to 2021, and the epidemiological characteristics of imported P. malariae and P. ovale malaria cases were analysed using a descriptive epidemiological method. The duration from onset of malaria to initial diagnosis, duration from initial diagnosis to definitive diagnosis, institutions of initial and definitive diagnoses, and proportion of correct malaria diagnosis at initial diagnosis were statistically analyzed. A total of 1 223 imported P. malariae and P. ovale malaria cases were reported in Anhui Province, Hubei Province, Zhejiang Province, Henan Province and Guangxi Zhuang Autonomous Region from 2014 to 2021, there were 158 P. malariae malaria cases (12.92%) and 1 065 P. ovale malaria cases (87.08%). Totally 98.53% (1 205/1 223) of the imported malaria cases were from Africa, with Angola (18.99%, 30/158), Nigeria (11.39%,18/158), Cameroon (10.76%, 17/158), Ghana (10.13%, 16/158) and the Democratic Republic of the Congo (10.13%,16/158) as predominant countries where P. malariae malaria cases were from, and Ghana (23.19%, 247/1 065), Cameroon (14.74%, 157/1 065), Nigeria (9.39%, 100/1 065) and Angola (6.95%, 74/1 065) as predominant countries where P. ovale malaria cases were from. There were significant differences in the duration from onset of malaria to initial diagnosis (χ2 = 27.673, P = 0.000) and duration from initial diagnosis to definitive diagnosis of P. malariae and P. ovale malaria cases (χ2 = 29.808, P = 0.000), and the proportions of correct initial diagnosis of P. malariae and P. ovale malaria cases were 38.61% (61/158) and 56.53% (602/1 065). There were 74.69% (118/158) of P. malariae malaria cases with definitive diagnosis in county-, city-, and province-level medical institutions, and 79.25% (844/1 065) of P. ovale malaria cases with definitive diagnosis in county- and city-level medical institutions and county-level centers for disease control and prevention. The imported P. malariae and P. ovale malaria cases in Anhui Province, Hubei Province, Zhejiang Province, Henan Province and Guangxi Zhuang Autonomous Region from 2014 to 2021 were mainly returned from Africa and the proportion of correct diagnosis of P. malariae and P. ovale malaria was low at initial diagnosis. Persistent improvements in the diagnostic capability of malaria are required in medical institutions.

Plasmodium Ovale Malaria-A Case Report from Tertiary Care Centre Central Kerala

Abstract Background: According to World Malaria Report 2019, 3% of the global malaria cases are reported from India. Most cases of malaria in India are due to infestation by Plasmodium falciparum (65%) and Plasmodium vivax (35%). Only a few thousand cases of Plasmodium malariae has been reported from foothill areas in Orissa. Malaria due to Plasmodium ovale is not very common in India and till date only 9 cases have been reported. We are reporting a case of P. ovale malaria which was diagnosed and treated at Government Medical College, Thrissur, Kerala, in a patient who had returned from Uganda. Diagnosis was made with the specific morphological features of these parasites like oval shape of parasitised RBCs, fimbriation of RBCs and very prominent shuffners dots. Interpretation & Conclusion: This is the first case of Pl. ovale reported from central Kerala. This case of plasmodium ovale malaria could be an isolated imported case and there are no reported cases of local transmission so far following detection of this case. Keywords: Malaria, Plasmodium ovale, fimbriation.

A case of severe Plasmodium ovale malaria with acute respiratory distress syndrome and splenic infarction in a male traveller presenting in Italy

BackgroundPlasmodium ovale malaria is usually considered a tropical infectious disease associated with low morbidity and mortality. However, severe disease and death have previously been reported.Case presentationA case of severe P. ovale malaria in a healthy Caucasian man with a triangle splenic infarction and clinical progression towards Acute Respiratory Distress Syndrome was reported despite a rapid response to oral chloroquine treatment with 24-h parasitaemia clearance.ConclusionPlasmodium ovale malaria is generally considered as a benign disease, with low parasitaemia. However, severe disease and death have occasionally been reported. It is important to be aware that occasionally it can progress to serious illness and death even in immunocompetent individuals.

Epidemiological characteristics of imported Plasmodium ovale malaria in Jiangsu Province from 2012 to 2020

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. 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. 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). 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.

Analysis of 11 imported severe malaria cases in Jiangsu

Objective This paper analyzed 11 cases of severe malaria in Jiangsu Province, summarized the causes of severe malaria, evaluated the effect of diagnosis and treatment, and provided scientific basis for formulating feasible treatment measures of severe malaria. Methods The case information, epidemiological investigation reports and inpatient medical records of 11 severe malaria cases in Jiangsu Province in 2019 were collected from the Infectious Disease Report Information Management System and Parasitic Disease Prevention and Control Information Management System. The onset time, clinical manifestations, diagnosis process and treatment of severe malaria cases were summarized and analyzed. Results Totally 11 cases of severe malaria, including 10 cases of falciparum malaria, and 1 case of ovale malaria, were all imported cases from abroad. The shortest time of living abroad was 22 days, and the longest was 1 070 days. Four cases had malaria while abroad. All of the 10 severe cases of falciparum malaria developed within one month after they returned to China, and three of them became ill on the day they returned home. One severe case of Plasmodium ovale began onset 134 days after returning home. The average time from onset to treatment was 2.5 days, and the average interval time from visit to diagnosis was 1.81 days. There were 3 cases of coma or shock, 3 cases of severe anemia, 4 cases of acute renal failure, and 1 case of acute respiratory distress syndrome. 1 case of Plasmodium ovale had severe anemia due to spontaneous rupture of spleen. Except one case of ovale malaria was treated with dihydroartemisinin piperaquine tablets plus primaquine tablets, the other 10 severe falciparum malaria cases were treated with artesunate injection for antimalarial treatment, and all of them were cured and discharged from hospital after receiving antimalarial treatment. 11 cases of severe cases, the shortest length of stay was 9 days, the longest was 40 days, with an average of 22.64 days; the minimum hospitalization cost was 9 270 yuan, the maximum was 177 174 yuan, with an average of 81 520.76 yuan. Conclusion It is necessary to strengthen multi department cooperation to improve patients’ awareness of timely treatment, strengthen the professional knowledge and professional training of medical staff, find and treat imported malaria cases as soon as possible, so as to prevent severe malaria caused by delayed diagnosis. 摘要:目的 对江苏省11例输入性重症疟疾病例进行分析,总结重症疟疾的成因、评价诊治效果,为制定切实可行 的重症疟疾救治措施提供科学依据。 方法 收集2019年江苏省11例重症疟疾病例传染病报告信息管理系统和寄生 虫病防治信息管理系统的个案信息、流行病学调查报告以及住院病历,对重症疟疾病例的发病时间、临床表现、诊断过 程、治疗情况进行汇总分析。 结果 11例重症疟疾病例中恶性疟10例、卵形疟1例,均为境外输入性病例,在境外生活 时间最短22 d最长1 070 d在国外期间有4例曾患过疟疾。10例恶性疟重症病例均在回国后一个月内发病,其中有 3例在回国当天就发病。1例卵形疟重症病例在回国后134 d才开始发病。11例重症疟疾病例发病至就诊平均时间为 2.5 d,就诊至确诊平均时间为1.81 d。重症表现为昏迷或休克3例、重度贫血3例、急性肾功能衰竭4例、急性呼吸窘迫 综合征1例。1例卵形疟由于出现自发性脾破裂引起重度贫血。除1例卵形疟病例给予双氢青蒿素哌喹片加服伯氨喹 片治疗外,其余10例恶性疟重症病例均采用青蒿琥酯注射抗疟治疗,接受抗疟治疗后均痊愈出院。11例重症病例,住 院天数最短9 d最长40 d平均22.64 d;住院费用最少9 270元,最多177 174元,平均81 520.76元。 结论 应加强多部 门合作,提高患者及时就诊意识;加强医务人员疟疾专业知识和业务的培训,尽早发现输入性疟疾病例并及时治疗,防 止因延误诊断造成的重症疟疾。

Epidemiological and clinical characteristics of imported malaria cases in Wuhan, 2016–2019

Objective To understand the epidemiology and clinical characteristics of imported malaria in Wuhan, and we provide reference for epidemic prevention and control. Methods The epidemiological and clinical characteristics of 85 imported malaria patients in Wuhan from 2016 to 2019 were retrospectively analyzed. Results From 2016 to 2019, all the 85 malaria cases reported were imported from abroad, including 3 foreign patients, 82 Chinese nationals, 68 cases of falciparum malaria (80.00%), 12 cases of vivax malaria (14.12%), 4 cases of ovale malaria (4.71%) and 1 case of malariae malaria (1.18%), and 0 cases of mixed infection. Imported malaria cases were reported from January to December. There was an obvious concentration trend in May, and a small peak in January and August. Imported malaria cases were mainly male young and middle-aged people, 79 cases (92.94%) from Africa and 6 cases (7.06%) from Asia. The patients were generally treated within 4 days after the onset of the disease. And 63.53% of the patients had a history of malaria, and had fever symptoms. Some of them were combined with chills, headache and disturbance of consciousness. And 83.53% were mild cases, 92.86% of severe cases were falciparum. Many patients were with anemia, and platelet, albumin decreased, combined with liver function, kidney function and other organ damage. Artemisinin and its derivatives were used to standardize the antimalarial treatment, and no deaths occurred. Conclusion The pressure of imported malaria in Wuhan is persistent. We should strengthen the monitoring and management of the working population and maintain an efficient malaria monitoring system. Standardized anti malaria and comprehensive treatment should be adopted for imported cases, and the prognosis is good. 摘要:目的 了解武汉市输人性疟疾的流行病学和临床特征,为疫情防控提供参考。 方法 对2016—2019年武 汉市85例输人性疟疾患者的流行病学和临床特征进行回顾性分析。 结果 2016—2019年报告的85例疟疾病例全为 境外输人病例,外籍患者3例,中国籍82例,恶性疟68例(80.00%),间日疟12例（14.12%),卵形疟4例(4.71%),三日疟 1例（1.18%),混合感染0例。1—12月都有输人性疟疾病例报告,5月份出现明显集中趋势,1、8月份存在小高峰。输人 性疟疾病例以青壮年男性为主,来源于非洲国家79例(92.94%),亚洲国家6例(7.06%)。患者一般在发病后4 d内就 诊,63.53%患者既往有疟疾病史,均有发热症状,部分合并寒战、头痛及意识障碍。83.53%为轻症病例,重症病例中恶 性疟占92.86%。不少患者出现贫血,血小板、白蛋白降低,合并肝功能、肾功能等多器官损害。采用青蒿素及衍生物规 范抗疟治疗,无死亡病例。 结论 武汉市面临的境外输人性疟疾压力持续存在,应加强对出国务工人员的监测和管 理,保持高效的疟疾监测体系;对于输人性病例采用规范的抗疟原虫及综合治疗手段,预后良好。

Clinical characteristics of 66 imported malaria cases in Xixi Hospital of Hangzhou

Objective To analyze the clinical data and drug treatment of malaria patients Xixi Hospital of Hangzhou, February 2014 – December 2019, and we provide reference data for early clinical diagnosis, assessment of severity and treatment, and promote rational clinical medication. Methods A total of 66 malaria patients admitted to hospital from February 2014 to December 2019 were collected to distinguish mild and severe cases. The laboratory test results and drug use of the two groups were compared, and the indicators of the two groups were analyzed by multi-factor binary Logistic Stepwise regression analysis. Results In the treatment of 17 patients with severe falciparum malaria, 10 patients artesunate injection and subsequent dihydroartemisinin-piperaquine tablets were used to consolidate the treatment, and the treatment effect was good. Among 34 patients with mild falciparum malaria, 28 patients were treated with dihydroartemisinin-piperaquine tablets alone, with sensitive effect and high cure rate. For 8 cases of vivax malaria and 4 cases of ovale malaria, 6 patients were treated with chloroquine phosphate plus primaquine phosphate 8-day regimen, and 6 patients were treated with artemisinin-based drugs, and the treatment effect was good. There was statistically significant difference in age, cure time, white blood cells (WBC), red blood cells, hemoglobin, platelets, aspartate transaminase, total bilirubin, C-reactive protein and procalcitonin (PCT) between mild group and severe group ( P <0.05). Multi-factor binary Logistic Stepwise regression analysis showed that the related factors influencing the severity of malaria included age, WBC and PCT. Conclusion Artemisinin-based injections combined with ACTs (Combinatorial therapy) are more effective in treating severe and malignant diseases. Artemisinin alone is effective in the treatment of vivax malaria and ovale malaria in the absence of preferred drugs. There are many factors, such as age, cure time, white blood cells, red blood cells, hemoglobin, platelets, aspartate transaminase, total bilirubin, C-reactive protein and procalcitonin, influencing the severity of malaria, among which age, leukocyte and procalcitonin are of great significance for the prediction and evaluation of malaria severity. 摘要:目的 分析杭州市西溪医院2014年2 月一2019年 12月收治的疟疾患者临床资料及药物治疗情况,为临床早 期诊断、评估轻重以及治疗提供参考数据,促进临床合理用药。 方法 收集2014年 2 月一2019年12月收治人院的66 例疟疾患者资料,分为轻症组和重症组,对两组患者的实验室检测指标结果、药物使用情况进行比较,并采用多因素二 元 Logistic 对两组患者的指标作逐步回归分析。 结果 17 例重症恶性疟患者治疗中, 10 例患者尽早、足量、足疗程使用 青蒿琥酯针及后续双氢青蒿素哌喹片巩固治疗,效果良好。 34 例轻症恶性疟疾患者, 28 例单独使用双氢青蒿素哌喹 片,效果敏感,治愈率高。 8 例间日疟和 4 例卵形疟, 6 例患者使用磷酸氯喹加磷酸伯氨喹八日方案, 6 例患者选用青蒿 素类药物,效果均良好。经Pearson单因素分析,轻症组与重症组在年龄、治愈时间、白细胞、红细胞、血红蛋白、血小板、谷草转氨酶、总胆红素、C-反应蛋白及降钙素原间差异具有统计学意义( P <0.05);经多元 Logistic 回归分析,影响疟疾轻 重症分型的相关因素包括:年龄、白细胞计数、降钙素原。 结论 青蒿素类注射液治疗后联用青蒿素类复方(ACTs)能 更有效治疗重症恶性疟疾。在缺乏首选药物的情况下单用青蒿素类药物治疗间日疟、卵形疟效果良好。影响疟疾发 病后重症化的因素有年龄、治愈时间、白细胞、红细胞、血红蛋白、血小板、谷草转氨酶、总胆红素、C-反应蛋白及降钙素 原,其中年龄、白细胞及降钙素原对疟疾严重程度的预测评估意义重大。

Epidemiological analysis of imported malaria in Fujian, 2015-2019

Objective To analyze the monitoring data, and explore the epidemic characteristics of imported malaria in Fujian Province from 2015 to 2019, so as to provide a scientific basis for the monitoring work after elimination of malaria. Methods The epidemiological data on malaria cases in Fujian Province, 2015-2019 were collected. The epidemic situation, the distribution of cases in different regions, age, gender and season, malaria diagnosis and treatment were analyzed by Microsoft Excel 2007 software. Results A total of 562 cases of malaria were reported in Fujian Province, 2015-2019. All cases were imported from overseas, mainly from African (516 case, 91.81%). All cases were confirmed in reference laboratories, comprising 428 (76.16%) falciparum malaria cases, 72 (12.81%) vivax malaria cases, 39 (6.94%) ovale malaria cases, 19 (3.38%) quartan malaria cases and 4 (0.71%) mixed infection cases. The median time, which was from onset to see a doctor and from seeing the doctor to diagnosis, was 1 day and 0 day, respectively. The cases of definitive diagnosis were 426 at initial diagnosis (75.80%), the prefecture level hospital was the preferred selection for patients to visit after onset of the disease (350 cases, 62.28%). By report area, most cases were mainly distribution in Gulou district (421 cases, 74.91%), Fuzhou city, and by the present address, 174 cases (30.96%) were distributed in Fuqing country, Fuzhou city. Most malaria cases (527, 93.77%) were young men, whose age from 20 to 49. The malaria cases were reported in each month across the year, the most cases were 66 and 63 in January and February, accounting for 11.74% (66/562) and 11.21% (63/562) of the total cases, respectively. 5 deaths were reported in Fujian Province, 2015-2019. Conclusions Imported malaria cases were still existed after elimination of malaria, the diagnosis and treatment capacity of medical institutions should be further strengthened in the future, so as to consolidate achievements in malaria eradication. 摘要:目的 分析2015—2019年福建省输人性疟疾监测数据,探讨福建省消除疟疾阶段疟疾流行特点,为福建省 消除疟疾后监测工作提供科学依据。 方法 收集2015—2019年福建省疟疾疫情数据资料,应用Microsoft Excel 2007软 件对疫情概况、三间分布及诊治情况进行描述性统计分析。 结果 福建省2015—2019年共报告输人性疟疾病例562 例,均为境外输人,其中516例（91.81%)来自非洲；562例均为确诊病例,其中恶性疟428例（76.16%)、间日疟72例 (12.81%)、卵形疟39例(6.94%)、三日疟19例（3.38%)、混合感染4例(0.71%)。报告病例中发病到就诊的中位时间为 1 d,从就诊到确诊的中位时间为0d;首诊确诊的426例（75.80%),首诊单位以地市级医疗机构为主,为350例（占 62.28%)。按报告地分,病例主要分布在福州市鼓楼区,为421例,占74.91 % ;按现住址分,病例主要分布于福州市福清 市,174例,占30.96%。病例以青壮年男性(20~49岁）为主,527例,占93.77% ;各月份均有病例分布,累计报告病例数 较多的是1、2月份,分别为66例和63例,占总病例数的11.74%(66/562)和11.21%(63/562)。2015—2019年全省共报告 死亡病例5例。 结论 消除疟疾后输人性疟疾病例依然存在,今后应进一步提髙医疗机构的诊治能力,巩固消除疟疾 成果。

Epidemiological characteristics of imported malaria in Mianyang, Sichuan, 2009-2019

Objective To analyze the epidemiological characteristics of imported malaria in Mianyang during the 20092019 period, and we provide scientific basis for the control of imported malaria. Methods The epidemic situation was collected from the infectious disease reporting information system and the epidemiological investigation data of imported malaria during 2009–2019 in Mianyang. The data were analyzed by descriptive epidemiological. Results A total of 169 imported malaria cases were reported during 2009–2019 in Mianyang, all were laboratory confirmed cases, with an average annual incidence rate of 0.43/100 000. There were 64 cases (37.876%) of vivax malaria, 91 cases (53.85%) of falciparum malaria, 5 cases (2.96%) of ovale malaria, 1 case (0.59%) of quartan malaria and 8 cases (4.73%) of mixed infections. Imported cases were reported all the year round, June and July had the most cases, with 22 cases each, accounting for 26.04% of the whole year. There were 10 cases (5.92%) imported from other province in China, 38 cases (22.49%) imported from 6 countries in Asia, 121 cases (71.60%) imported from 24 countries in Africa. Imported malaria cases have been reported in 10 counties. The average age of the cases was (38.45±11.74) years. Malaria cases were majorly young men working as peasant and migrant workers. The average time from symptom appearing to being diagnosed was 4.18 d, 39.05% and 56.21% of the patients were diagnosed in municipal and county medical treatment units, respectively. Conclusion The situation of imported malaria from overseas is still serious in Mianyang. It is important to improve the malaria diagnosis and treatment, and strengthen the health education of migrant workers and their families in order to achieve better prevention and control of imported malaria in the area and put an end to secondary cases. 摘要:目的 分析 2009—2019 年四川省绵阳市输人性疟疾的流行病学特征, 为进一步加强输人性疟疾防治工作提 供科学依据。 方法 通过法定传染病报告信息管理系统, 收集绵阳市 2009—2019 年疟疾病例流行病学资料和病例个 案调査资料。采用描述性流行病学方法对这些资料进行统计学分析。 结果 2009—2019 年绵阳市共有 169 例输人性 疟疾病例, 均为实验室确诊病例, 年均发病率 0.43/10 万。其中间日疟64 例 (37.87%)、恶性疟 91 例(53.85%)、三日疟1 例 (0.59%)、卵型疟 5 例 (2.96%)、混合感染 8 例 (4.73%)。输人性病例全年均有分布, 6 月和 7 月最多, 均为 22 例, 占全年 的26.04%。169例输人性疟疾病例中, 10 例 (5.92%)来自国内其他省份, 38 例 (22.49%)来自亚洲 6 个国家, 121 例 (71.60%)来自非洲 24 个国家。全市10 个县市区均有输人性疟疾病例报告。病例平均年龄 (38.45±11.74) 岁, 主要为男 性青壮年, 职业以农民、工人为主。发病至诊断时间平均为 4.18d, 39.05%、56.21% 的病例分别在县级、市级医疗机构确 诊。 结论 绵阳市输人性疟疾疫情仍然严峻, 应引起高度重视, 需进一步加强输人性疟疾防控;提高医务人员疟疾诊 治能力, 完善疟疾监测体系, 加强对重点地区重点人群尤其是出境人员和高疟区回归人员的健康教育, 防止继发病例 发生。

Epidemiological characteristics of imported malaria cases in Huai’an, Jiangsu, 2012-2019

Objective To analyze the epidemiological characteristics of 258 imported malaria cases of Huai’an city, and we provide scientific basis for improving malaria diagnosis and monitoring capacity, preventing secondary transmission of imported malaria, and consolidating the achievements of malaria elimination work. Methods Descriptive analysis was conducted by collecting the epidemiological survey data, basic situation table of epidemic spot, report of epidemic investigation and medical record data related to malaria diagnosis and treatment in hospital in Huai’an city from 2012 to 2019. Results All the types of malaria were detected in Huai’an city, including 203 cases of falciparum malaria, 4 cases of vivax malaria, 39 cases of ovale malaria, 8 cases of quartan malaria and 4 cases of mixed infection. These cases had a wide range of importing countries (22 countries). There were 255 cases from Africa, 2 cases from Oceania, and 1 case from Southeast Asia, corresponding to the proportion of 98.83%,0.78% and 0.39% respectively. The number of living days abroad ranged from 15 to 2 990 days, and the number of onset times from 0 to 30. Before the Spring Festival, before the wheat harvest and before the autumn harvest were the three peaks of cases returning to China, accounting for 72.48% (187/258). Most of the reported cases are from District Qingjiangpu, which were 109 cases accounting for 42.25%. The young adults aging from 20 to 49 years old account for 83.33% (215 cases). There are 131 cases detected in the group of the migrant workers, accounting for 50.78%. The average time interval from returning home to onset was 9.5 days, and the longest was 634 days. Among them, 93.10% (189/203) of patients with falciparum malaria became ill within 30 days. The average interval between onset and diagnosis of patients was 2 days, and 254 cases were diagnosed within 30 days (98.45%). Conclusion Since 2012, all the reported malaria cases were imported. The health education for personnel shuttling between high malaria areas and screening for malaria among returnees should be strengthened. We should improve the ability of malaria diagnosis and treatment of medical institutions above the county level to review blood tablets. These methods can avoid the death cases and the secondary spread of the imported malaria, and consolidate the achievements in the elimination of the malaria. 摘要: 目的分析淮安市 258 例输人性疟疾病例流行病学特征,为提升疟疾诊治能力和监测响应水平,防止输人性 疟疾的继发传播,巩固消除疟疾工作成果提供科学依据。 方法 收集淮安市 2012—2019 年疟疾病例流行病学个案调 査表、疫点基本情况表、疫点调査与处置报告、医院有关疟疾诊治的病历资料等,对其进行描述性分析。 结果 淮安市 2012—2019 年输人性疟疾 258 例,其中恶性疟 203 例,间日疟 4 例,卵形疟 39 例,三日疟8例,混合感染 4 例。输人地广 泛,涉及 22 个国家,其中非洲 255 例、大洋洲2例和东南亚 1 例,分别占总病例数 98.83%、0.78%和0.39%。国外居住15~2 990 d,期间发病次数0~30次；回国多集中在春节前、麦收前和秋收前三个高峰,占总回国人数72.48%(187/258)。清 江浦区报告病例数最多,为109例,占42.25%;20~<49岁青壮年215例,占总病例数的83.33%;民工131例,占总病例数 的50.78%;回国至发病时间间隔平均为9.5 d,最长为634 d,其中93.10%(189/203)的恶性疟患者在回国后30 d内发病。患者自发病至确诊时间平均为2 d,30 d内确诊254例,占总数的98.45%。 结论 淮安市自2012年以来全市报告的均 是境外输人性疟疾病例,应加强对往返于高疟区人员的健康教育和归国人员的疟疾筛査,提高县级以上医疗机构的疟 疾诊治和疾控部门复核血片的能力,避免死亡病例发生和防止输人性疟疾继发传播,巩固消除疟疾工作成果。

Analysis of initial laboratory diagnosis of malaria and its accuracy compared with re-testing from 2013 to 2018 in Yunnan Province, China

BackgroundAccording to China’s Malaria Eradication Action Plan, malaria cases diagnosed and reported by health authorities at the county level must be further re-confirmed by provincial laboratories. The Yunnan Province Malaria Diagnostic Reference Laboratory (YPMDRL) began the synchronous implementation of microscopic examinations and nested polymerase chain reaction (nested-PCR) testing to re-test the malaria cases initially diagnosed by county-level laboratories and to evaluate the consistency of Plasmodium species identified between by YPMDRL and by the county-level laboratories from 2013 to 2018 in Yunnan Province.MethodsData on malaria initial diagnosis completed by county-level laboratories in Yunnan Province were collected weekly from the “China Disease Prevention and Control Information System” from 2013 to 2018. The YPMDRL performed Plasmodium microscopic examination and 18S rRNA gene nested-PCR testing on every malaria case managed by the China Disease Prevention and Control Information System. The re-testing detection results were fed back to the initial diagnosis and reporting unit for revision of malaria case types.ResultsA total of 2,869 malaria cases were diagnosed and reported by county-level laboratories in Yunnan Province from 2013 to 2018. The re-testing rate was 95.6% (2,742/2,869), and the re-testing rate increased from 2013 to 2018. Among the re-tested 2,742 cases, 96.7% (2651/2742), 2.2% (59/2742), and 1.1% (32/2742) were doubly examined by microscopy and by nested-PCR, only by microscopy, and only by nested-PCR, respectively. The total Plasmodium species accuracy rate at county-level laboratories was 92.6% (2,543/2,742) reference to the diagnosis by YPMDRL. Among the inconsistent 199 cases, they were identified as including 103 negative cases, 45 falciparum malaria cases, 30 vivax malaria cases, 11 ovale malaria cases, and 10 malariae malaria cases by YPMDRL. From 2013 to 2018, the revised and registered malaria cases by the China Disease Prevention and Control Information System in Yunnan Province was 2,747 cases, including 2,305 vivax malaria cases, 421 falciparum malaria cases, 11 ovale malaria cases, and 10 malariae malaria cases.ConclusionsThe double re-testing strategy by microscopy and by gene testing increases the accuracy of diagnoses malaria in Yunnan Province, and gene testing can reliably differentiate Plasmodium species. The re-testing results provided by YPMDRL are the authoritative basis for revising malaria kind in Yunnan Province.

Polymorphism analysis of propeller domain of k13 gene in Plasmodium ovale curtisi and Plasmodium ovale wallikeri isolates original infection from Myanmar and Africa in Yunnan Province, China

BackgroundEighteen imported ovale malaria cases imported from Myanmar and various African countries have been reported in Yunnan Province, China from 2013 to 2018. All of them have been confirmed by morphological examination and 18S small subunit ribosomal RNA gene (18S rRNA) based PCR in YNRL. Nevertheless, the subtypes of Plasmodium ovale could not be identified based on 18S rRNA gene test, thus posing challenges on its accurate diagnosis. To help establish a more sensitive and specific method for the detection of P. ovale genes, this study performs sequence analysis on k13-propeller polymorphisms in P. ovale.MethodsDried blood spots (DBS) from ovale malaria cases were collected from January 2013 to December 2018, and the infection sources were confirmed according to epidemiological investigation. DNA was extracted, and the coding region (from 206th aa to 725th aa) in k13 gene propeller domain was amplified using nested PCR. Subsequently, the amplified products were sequenced and compared with reference sequence to obtain CDS. The haplotypes and mutation loci of the CDS were analysed, and the spatial structure of the amino acid peptide chain of k13 gene propeller domain was predicted by SWISS-MODEL.ResultsThe coding region from 224th aa to 725th aa of k13 gene from P. ovale in 83.3% of collected samples (15/18) were amplified. Three haplotypes were observed in 15 samples, and the values of Ka/Ks, nucleic acid diversity index (π) and expected heterozygosity (He) were 3.784, 0.0095, and 0.4250. Curtisi haplotype, Wallikeri haplotype, and mutant type accounted for 73.3% (11/15), 20.0% (3/15), and 6.7% (1/15). The predominant haplotypes of P. ovale curtisi were determined in all five Myanmar isolates. Of the ten African isolates, six were identified as P. o. curtisi, three were P. o. wallikeri and one was mutant type. Base substitutions between the sequences of P. o. curtisi and P. o. wallikeri were determined at 38 loci, such as c.711. Moreover, the A > T base substitution at c.1428 was a nonsynonymous mutation, resulting in amino acid variation of T476S in the 476th position. Compared with sequence of P. o. wallikeri, the double nonsynonymous mutations of G > A and A > T at the sites of c.1186 and c.1428 leads to the variations of D396N and T476S for the 396th and 476th amino acids positions. For P. o. curtisi and P. o. wallikeri, the peptide chains in the coding region from 224th aa to 725th aa of k13 gene merely formed a monomeric spatial model, whereas the double-variant peptide chains of D396N and T476S formed homodimeric spatial model.ConclusionThe propeller domain of k13 gene in the P. ovale isolates imported into Yunnan Province from Myanmar and Africa showed high differentiation. The sequences of Myanmar-imported isolates belong to P. o. curtisi, while the sequences of African isolates showed the sympatric distribution from P. o. curtisi, P. o. wallikeri and mutant isolates. The CDS with a double base substitution formed a dimeric spatial model to encode the peptide chain, which is completely different from the monomeric spatial structure to encode the peptide chain from P. o. curtisi and P. o. wallikeri.

Severity and mortality of severe Plasmodium ovale infection: A systematic review and meta-analysis.

Plasmodium ovale can infect humans, causing malaria disease. We aimed to investigate the severity and mortality of severe P. ovale infection to increase the awareness of physicians regarding the prognosis of this severe disease and outcome-related deaths in countries in which this disease is endemic. Articles that were published in the PubMed, Scopus, and ISI Web of Science databases prior to January 5, 2020 and reported the prevalence of severe P. ovale infection were systematically searched and reviewed. Studies that mainly reported severe P. ovale infection according to the 2014 WHO criteria for the treatment of malaria were included. Two reviewers selected, identified, assessed, and extracted data from studies independently. The pooled prevalence of severe P. ovale mono-infections was estimated using the command “metaprop case population, random/fixed”, which yielded the pooled estimate, 95% confidence interval (CI) and the I2 value, indicating the level of heterogeneity. Meta-analyses of the proportions were performed using a random-effects model to explore the different proportions of severity between patients with P. ovale and those with other Plasmodium species infections. Among the eight studies that were included and had a total of 1,365 ovale malaria cases, the pooled prevalence of severe P. ovale was 0.03 (95% CI = 0.03–0.05%, I2 = 54.4%). Jaundice (1.1%), severe anemia (0.88%), and pulmonary impairments (0.59%) were the most common severe complications found in patients infected with P. ovale. The meta-analysis demonstrated that a smaller proportion of patients with P. ovale than of patients with P. falciparum had severe infections (P-value = 0.01, OR = 0.36, 95% CI = 0.16–0.81, I2 = 72%). The mortality rate of severe P. ovale infections was 0.15% (2/1,365 cases). Although severe complications of P. ovale infections in patients are rare, it is very important to increase the awareness of physicians regarding the prognosis of severe P. ovale infections in patients, especially in a high-risk population.

Diagnosis and Molecular Analysis on Imported Plasmodium ovale curtisi and P. ovale wallikeri Malaria Cases from West and South Africa during 2013-2016.

Majority of the imported malaria cases in Korea is attributed to Plasmodium falciparum and P. vivax infections, whereas P. malariae and P. ovale infections are very rare. Falciparum and ovale malaria are mostly imported from Africa, while most of the vivax malaria cases are imported from Southeast Asia. Here, we report 6 Korean imported ovale malaria cases (4 males and 2 females) who had visited in Africa during 2013–2016. These subjects were diagnosed with P. ovale based on microscopic findings, Plasmodium species-specific nested-PCR, and phylogenetic clade using 18S rRNA gene sequences. We identified 2 P. ovale subtypes, 1 P. ovale curtisi (classic type) and 5 P. ovale wallikeri (variant type). All patients were treated with chloroquine and primaquine, and no relapse or recrudescence was reported for 1 year after treatment. With increase of travelers to the countries where existing Plasmodium species, the risk of Plasmodium infection is also increasing. Molecular monitoring for imported malaria parasites should be rigorously and continuously performed to enable diagnosis and certification of Plasmodium spp.

Epidemiological analysis of malaria prevalence in Jiangsu Province in 2017

To understand the malaria epidemic situation and characteristics in Jiangsu Province in 2017, so as to provide the evidence for formulating the targeted strategy of malaria elimination. The data of malaria cases in Jiangsu Province in 2016 were collected from China's Routine Diseases Surveillance Information System (CRDSIS). Totally, 239 imported malaria cases were reported in Jiangsu Province in 2017, and the cases decreased by 22.40% compared to 308 cases in 2015. Except 2 malaria case caused by blood transfusion, the rest patients were all imported. Among them, there were 163 falciparum malaria cases, 21 vivax malaria cases, 11 quartan malaria cases, 43 ovale malaria cases, and 1 mixed infection case (Plasmodium falciparum and P. ovale). The numbers of imported cases of Nantong (39 cases, 16.32%), Suzhou (26 cases, 10.88%), Taizhou (25 cases, 10.46%), Huai'an (24 cases, 10.04%), and Lianyungang (22 cases, 9.21%) ranked in the top 5 cities across Jiangsu Province, the malaria cases in the five cities accounted for 56.90% (136/239). The infection source areas of the imported malaria cases included Africa (225 cases), Asia (8 cases), Oceania (2 cases), and South America (2 cases). Jiangsu Province has no local malaria cases for 6 consecutive years. Despite the imported cases in 2017 decreased some-what compared to that in 2016, it is still necessary to strengthen the surveillance of imported malaria cases and improve malaria diagnosis and treatment in the whole province.

Epidemic situation of malaria in Qingdao City from 2012 to 2017

To investigate the epidemic situation and its epidemic characteristics of malaria in Qingdao City from 2012 to 2017, so as to provide the evidence for the prevention and control of malaria in this city. The data of cases and epidemiological characteristics of malaria in Qingdao City, 2012-2017 were collected from the China's disease prevention and control system infectious disease report information management system and parasitic disease prevention and control information management system, and analyzed. A total of 103 cases of malaria were reported in Qingdao City from 2012 to 2017, and all of them were imported. Among them, 98 (95.15%) were imported from Africa and 5 (4.85%) from Asia. There were 92 laboratory confirmed cases (89.32%) and 11 (10.68%) clinically diagnosed cases. The highest incidence occurred in 2016 (0.28/105) . According to the classification of cases, there were 87 falciparum malaria cases (84.47%), 13 vivax malaria cases (12.62%), and 3 ovale malaria cases (2.91%) . These patients were mainly young men, and the male to female ratio was 19.6∶1. There were malaria case reports in each month, and the peak onset season was not obvious. Newly diagnosed and confirmed units were mainly municipal medical institutions; the median of onset-definite diagnosis was 4 days. There was one death case, but there were no recurrence, reburning, and imported secondary cases. There were no local malaria cases in Qingdao City from 2012 to 2017. The prevention and control of imported malaria is the focus of the future work.

Epidemic situation of imported malaria in Beijing City, 2017

To explore the epidemic situation and epidemiological characteristics of imported malaria in Beijing City in 2017, so as to provide the evidence for developing malaria control interventions. The data of registered malaria cases were collected and analyzed by using descriptive epidemiological methods. A total of 90 malaria cases were reported in Beijing in 2017, and all the cases were imported. The 90 cases included 74 cases of falciparum malaria (82.22%), 10 cases of vivax malaria (11.11%), 4 cases of ovale malaria (4.45%) and 2 cases of malariae malaria (2.22%), and 97.78% of the malaria patients were at ages of 19 to 61 years. Eighty-one cases (90.00%) came back from Africa and 44 cases (48.89%) suffered two or more courses of malaria. Among the 66 patients with disease onset after returning from abroad, 53 cases (80.30%) of falciparum malaria had an onset within two weeks. The patients went to the malaria-endemic areas were mainly because of working (46.34%) or business (41.46%). Eighty-nine cases used mosquito nets while living in malaria-endemic areas and 59 cases used mosquito repellents in addition. The prevention and control for imported malaria is still the major target for the surveillance in Beijing City. The highly efficient surveillance system for malaria should be sustained, and the awareness of the disease among migrant workers should be enhanced.

Evaluation of malaria elimination surveillance in Liyang City from 2010 to 2016

To evaluate the effect of malaria elimination monitoring in Liyang City, so as to provide the evidence for formulating control strategies and measures of malaria elimination. The monitoring data about the epidemic situation, blood tests of feverish patients and epidemiology investigation of individual malaria patients in Liyang City from 2010 to 2016 were collected and analyzed by the descriptive epidemiology method. From 2010 to 2016, there were 67 malaria cases in total. Totally 39 196 feverish patients had blood tests for Plasmodium, and 65 of them showed positive and the positive rate was 0.17%. The other 2 cases of microscopy negative were treated with anti-malarial drugs by themselves after the onset of fever, and no Plasmodium was detected in the microscopy, but the tests with malaria rapid diagnostic kit (RDTs) were positive. Among all the 67 cases, there were 49 falciparum malaria cases, 13 ovale malaria cases and 5 vivax malaria cases. All the 67 malaria cases were imported, and the number of cases from Africa was 63 (94.03%). Totally 97.01% (65/67) of the malaria patients were male and most of them were young adults. The patients aged 30 to 49 years accounted for 73.13% (49/67) and 80.60% (54/67) of them were farmers. There were malaria cases in all the 10 towns of the city, and the time of onset had no obvious seasonal characteristics. The timely rate of case report, timely rate of blood film review, standardized treatment rate, epidemiological case investigation rate, and epidemic focus investigation and disposal rate were all 100%. There were 18 076 people with the active case investigation, but no malaria parasite positive carriers were found. The mosquito vector monitoring was performed with the methods of mosquito trap lamp and human bait half night trap, and 187 and 78 Anopheles mosquitoes were captured respectively, and all the parasites were Anopheles sinensis. A total of 88 person-times were performed for the Plasmodium examinations with microscopy and RDTs (one blood sample, two detections) in Liyang City Center for Disease Prevention and Control from 2012 to 2016, and 35 person-times were positive, including 28 person-times of Plasmodium falciparum and 7 person-times of P. ovale, and there was no statistically significant difference between the detection rates of P. falciparum, and P. ovale (adjusted χ2 = 0.05, P > 0.05). There were 34 RDTs positive cases, including 14 cases of malignant malaria, and 17 cases of malignant malaria or mixed infections of P. falciparum with other three kinds of Plasmodium parasites, and 3 cases of single infection or mixed infections of other three kinds of Plasmodium parasites, and there was a statistically significant difference among them in the positive RDTs detection rates (adjusted χ2 = 13.75, P < 0.05). There are still imported malaria cases and there is the risk of malaria retransmission in Liyang City. Therefore, it is necessary to strengthen the malaria surveillance work and the management of infectious sources, so as to consolidate the achievements of malaria elimination in the future.

Epidemiological analysis of malaria prevalence in Jiangsu Province in 2015

Objective To understand the malaria epidemic situation and characteristics in Jiangsu Province in 2015, so as to provide the evidence for malaria elimination. Methods The data of malaria cases in Jiangsu Province in 2015 were collected from China's routine diseases surveillance information system. Results Totally 405 imported cases were reported in Jiangsu Province in 2015, and the cases increased by 14.08% compared with those in 2014. All the malaria cases were imported, and 5 cases (1.23%) were from Southeast Asia and 400 (98.77%) were from 25 African countries or regions. The imported malaria cases were reported in 13 cities across Jiangsu Province, where Taizhou, Lianyungang, Nantong, Huaian and Yangzhou cities accounted for 68.64% of all the cases in the province. Jiangsu Institute of Parasitic Diseases (JIPD) reference lab checked all the cases and classified 299 falciparum malaria cases, 13 vivax malaria cases, 18 quartan malaria cases, 71 ovale malaria cases, and 4 mixed Plasmodium infection cases. Conclusions In Jiangsu Province, there are no local malaria cases for 4 consecutive years, but the imported cases are on the rise. Compared to 2014, the imported vivax cases increased significantly in 2015. It should be the key points to strengthen the surveillance of imported malaria cases, improve malaria diagnosis and treatment abilities for all levels of medical institutions, and promote the abilities of Plasmodium check, and focus survey and disposal of all Center for Disease Control (CDC) staffs across Jiangsu Province.

Epidemiological analysis and countermeasures discussion on imported malaria in Zhangjiagang City

Objective To analyze the epidemiological characteristics of imported malaria in Zhangjiagang City. Methods The epidemiological data were collected and retrospectively analyzed for the distribution, cost, and exit-entry mode and port of imported malaria cases in Zhangjiagang City from 2005 to 2015. Results There were 25 imported malaria cases in Zhangjiagang City from 2005 to 2015, and among them, there were 16 cases of falciparum malaria (64%), 6 cases of vivax malaria (24%), and 3 cases of ovale malaria (12%); there was 1 cases of critically ill (4%), there were 8 cases of serious ill (32%) and 16 cases of mild ill (64%). The time of onset was in accordance with the circular distribution. The peak of the incidence of the imported malaria was one month earlier than that of the domestic infection. The seasonal peak was gentle, and there was also the occurrence in the non-epidemic season in the city. The imported malaria patients were mainly from Africa, followed by Southeast Asia and Oceania. Conclusion The information technology should be applied to improve the key population coverage on the basis of improving the ability of malaria diagnosis and treatment of medical staff and the multi-sector's cooperation for the imported malaria prevention and control in Zhangjiagang City.