2011-2017年江苏省疟疾镜检工作质量分析

目的 了解消除疟疾阶段江苏省发热病人疟原虫血涂片制作质量和实验室人员疟原虫镜检能力,为各级疟疾诊断实验室建设和消除疟疾效果评价提供科学依据。方法 对2011-2017年江苏省全部网报疟疾病例血涂片和随机抽取的县级疟疾中心镜检站已复核阴性血片,以及辖区内门诊镜检站已检阴性血片进行镜检复核,从血片制作、染色、清洁度、镜检结果及虫种符合情况进行综合分析。结果 2011-2017年共抽检复核已检血片19 109张,血片制作、染色、清洁度合格率分别为87.5%、89.3%、87.6%,不同年份血片质量差异有统计学意义（P均< 0.05）,并有逐年增高的趋势。不同设区市血片质量差异有统计学意义（P < 0.05）。复核2012-2017年网报疟疾病例血片1 860张,总符合率为87.4%,阳性符合率为98.9%。恶性疟、间日疟、三日疟、卵形疟、混合感染虫种符合率分别为95.4%、33.3%、56.0%、76.5%、9.1%,差异有统计学意义（P < 0.05）。2012-2017年不同年份网报疟疾病例血片复核总符合率分别为85.0%、90.1%、86.0%、85.3%、90.0%、87.6%,差异无统计学意义（P > 0.05）。结论 江苏省基层门诊镜检站的血片质量达到省疟疾诊断参比实验室制定的判定标准,血片诊断符合率较高,但虫种鉴别能力有待进一步提高。     

上海市2例输入性卵形疟误诊病例的实验室诊断分析

上海市疾病预防控制中心(简称上海市疾控)采用显微镜检查、疟疾快速诊断检测(RDT)和疟疾核酸检测[NP-2002法、多重PCR法和荧光定量PCR (qPCR)法]对2例虫种分型存在争议的输入性疟疾患者的血样进行实验室诊断与分析。结果显示,上海市A区疾病预防控制中心(简称A区疾控)对患者1的初检结果为镜检查见恶性疟原虫,RDT检测结果为恶性疟阳性,未作核酸检测;上海市疾控对患者1的复核结果是镜检查见卵形疟原虫,RDT检测结果为恶性疟阳性,核酸检测结果为卵形疟原虫阳性。B区疾控分别采用镜检、 RDT和qPCR法对患者2进行初检,结果均为间日疟阳性;上海市疾控对患者2的复核结果为镜检查见卵形疟原虫,RDT结果为阴性,核酸检测结果为卵形疟阳性。     

应用巢式PCR评价低流行区疟疾诊断结果

目的初步评价大连市疾控人员对疟疾的诊断能力,为低流行区疟疾诊断方法的选择提供理论依据。方法收集2010--2012年大连市上报的27例疟疾阳性病例的血液样本．应用巢式PCR（nest—PCR）方法对诊断结果进行复核：以复核结果为标准,比较镜检和快速诊断试剂盒（rapid diagnosistest．RDT）方法的检测敏感性及对虫种鉴定的正确率。结果27份样本的巢式PCR结果为恶性疟23份,间日疟2份,卵形疟l份,阴性1份,无混合感染。镜检对阳性样本的敏感度为76．9％（20／26）,远低于RDT方法的96．2％（25／26）;镜检和RDT联合使用,敏感度可达100％。对虫种的鉴别,镜检对阳性样本的正确检测率为50％（13／26）：RDT方法仅能鉴别恶性疟和非恶性疟．对恶性疟阳性样本的正确检测率为100％（23／23）。结论采用镜检和RDT联合应用的方法,能够提高检测的敏感性。建议在有条件的疾控单位建立人体疟原虫的分子检测体系．更有效地防止对疟疾病例的漏诊和误诊。     

2017-2019年湖北省疟疾诊断参比实验室病例复核结果分析

目的　分析湖北省疟疾诊断参比实验室对网络报告疟疾病例的复核结果,为进一步提高全省疟疾防控水平提供科学依据。 方法　由湖北省疟疾诊断参比实验室对全省2017—2019年网络报告疟疾病例样本采用镜检和巢式PCR法进行复核,并分析病例和虫种等符合情况。 结果　2017—2019年,湖北省共有网络报告疟疾病例410例;湖北省疟疾诊断参比实验室共复核407例样本,确诊疟疾病例374例,总体疟疾诊断阳性符合率为91.89%（374/407）、虫种符合率为89.04%（333/374）;不同市（州）报告疟疾病例复核阳性符合率为50.00%～100.00%、虫种符合率为66.67%～100.00%,差异均有统计学意义（χ2 = 40.46、42.30,P均 < 0.01）;恶性疟原虫、间日疟原虫、三日疟原虫、卵形疟原虫复核虫种符合率分别为95.80%、100.00%、58.33%和51.92%,差异有统计学意义（χ2 = 76.66,P < 0.01）;镜检法与巢式PCR法检测结果一致率为89.83%（362/403）。结论　湖北省各级医疗卫生机构疟疾诊断质量总体较高,但部分地区诊断能力仍有待提高。     

两种检测方法在间日疟和卵形疟诊断中的应用分析

目的分析疟原虫镜检和巢式PCR检测间日疟和卵形疟效果。方法收集2012～2016年输入性间日疟和卵形疟病例血样,巢式PCR检测疟原虫ssRNA基因,并与显微镜检结果进行比对。结果显微镜检和巢式PCR检测71份血样,间日疟、卵形疟、混合感染分别占74.6%、25.4%、0%和63.4%、29.6%、7%,符合率为81.7%;亚洲23份血样,镜检与巢式PCR均为间日疟,符合率为100%,巢式PCR检测非洲血样48份,间日疟、卵形疟和混合感染分别占45.8%、43.8%和10.4%,镜检与巢式PCR符合率为72.9%;巢式PCR检测26份卵形疟,经典curtisi、变种wallikeri和混合感染分别占80.8%、11.5%和7.7%,检出变种wallikeri总数占卵形疟19.2%。结论巢式PCR检测疟原虫虫种鉴别优于传统镜检法,可提高疟疾病例诊断水平。     

6 例不同时段发病的混合感染疟疾病例分析

目的 对 6 例不同时段发病的境外输入性混合感染疟疾病例进行调查分析,为输入性疟疾防控提供参考。 方法 收集该 6 例病例回国后各次发病的网报和专报信息、流调报告,以及基层医疗机构的临床病例资料和省级疟疾诊断参比实验室镜检、PCR 复核结果。 结果 6 例疟疾病例,均有境外生活史,在境外居住时间最短为 10 d,最长为1 229 d;回国后至第二次发病均无再出国史。 6 例疟疾病例从回国至第一次发病间隔 1~ 10 d,第一次发病均被确诊为恶性疟原虫感染,接受抗疟治疗后均痊愈出院。 从第一次发病痊愈出院至再次发病间隔时间为 22~133 d,第二次发病3 例为三日疟原虫感染、3 例为卵形疟原虫感染。 两次发病感染疟原虫虫种均经江苏省疟疾诊断参比实验室镜检和PCR 复核并确认。 对 6 例病例第二次发病痊愈后随访 1 年以上,健康状况良好。 结论 6 例疟疾病例是不同时段发病的境外输入病例,为恶性疟与卵形疟或三日疟混合感染,今后应加强该类病例的防控,巩固消除疟疾成果。     

2014年江苏省疟疾疫情流行病学分析

目的 掌握2014年江苏省疟疾疫情及流行特征,为制订和调整适合本省的消除疟疾策略和措施提供依据。方法 对2014年全省网络报告疟疾疫情和专报系统的流行病学调查资料进行统计分析。 结果 2014年江苏省共报告疟疾355例,较2013年（341例）上升4.11%,发病率为0.046/万。355例均为国外输入性病例,4例（1.13%）来自东南亚,351例（98.87%）来自21个非洲国家或地区。全省13个市均有疟疾病例报告,其中淮安市（56例）、南通市（46例）、连云港市（42例）、扬州市（41例）和泰州市（40例）报告病例数占全省总数的63.38%（225/355）。省疟疾诊断参比实验室对355份样本进行复核,发现恶性疟292例、间日疟4例、三日疟10例、卵形疟46例,混合感染3例。病例追踪观察发现,355例疟疾病例中有6例恶性疟出现了再燃,有4例卵形疟和1例间日疟出现了复发。结论　江苏省已连续3年无本地感染疟疾病例,初步实现消除疟疾目标,但境外输入性疟疾病例仍较多,且感染虫种呈多样性,加强境外输入性疟疾监测、提高各级医疗机构相关人员对疟疾的诊断和治疗能力、针对性地开展重点人群健康教育,是本省疟疾防控工作的重点。     

2015年重庆市3例输入性卵形疟原虫wallikeri亚种感染病例的实验室诊断

目的   分析重庆市2015年3例输入性卵形疟原虫wallikeri亚种感染病例病原、抗原及核酸检测过程,减少卵形疟原虫的漏诊和误诊。 方法  收集流行性病学资料及血样,按照WS259-2015疟疾的诊断标准对3例血样进行血涂片镜检、快速疟疾诊断试纸条检测（RDT）及巢式PCR检测。 结果  3例患者均为非洲务工归国人员,并都有疟疾发病史。血涂片镜检结果,3例血样均为疟原虫阳性。RDT检测结果3例均为除恶性疟以外其他疟原虫阳性。国家参比实验室推荐的巢式PCR检测DNA,3例均为阴性。用卵形疟原虫wallikeri亚种的种特异性引物的PCR检测,3例均为阳性。 结论  根据镜检、RDT和卵形疟原虫wallikeri亚种种特异性PCR检测确定,重庆市2015年首次发现了3例卵形疟原虫wallikeri亚种感染输入病例,为重庆地区首次发现。     

福建省南平市一例输入性卵形疟的诊断

对1例误诊为间日疟的输入性病例进行复核,收集患者流行病学资料和血样,进行镜检、快速疟疾诊断试纸条检测(RDT)和巢式PCR检测,证实该输入性疟疾患者为南平市首例卵形疟病例。     

2015年江苏省疟疾疫情流行病学分析

目的 掌握江苏省2015年疟疾疫情及流行特征,为如期实现本省的消除疟疾目标提供依据。方法 对2015年全省网络报告疟疾疫情和专报系统的流行病学调查资料进行统计分析。结果 2015年江苏省共报告疟疾405例,较2014年（355例）上升14.08%。均为境外输入病例,5例（1.23%）来自东南亚,400例（98.77%）来自25个非洲国家或地区。全省13个市均有输入性疟疾病例报告,其中泰州市、连云港、南通市、淮安市和扬州市报告病例数占全省总数的68.64%（278/405）。省疟疾诊断参比实验室对405份样本进行复核,发现恶性疟299例、间日疟13例、三日疟18例、卵形疟71例、混合感染4例。结论 江苏省已连续4年无本地感染疟疾病例,但境外输入性疟疾病例仍呈上升趋势,且输入性间日疟病例较2014年明显增加。加强境外输入性疟疾监测,提高各级医疗机构相关人员对疟疾的诊断和治疗能力、提升疾控机构专业人员病原复核、疫点调查和处置能力是本省疟疾防控工作的重点。     

Prospective risk of morbidity in relation to malaria infection in an area of high endemicity of multiple species of Plasmodium.

In an area of Papua New Guinea with high prevalence of Plasmodium falciparum (39.6%), Plasmodium vivax (18.3%), and Plasmodium malariae (13.8%), cross-sectional analysis found P. falciparum infection to be independent of the other species despite heterogeneities in transmission. Plasmodium vivax and P. malariae infections were negatively correlated. Plasmodium malariae infection was positively associated with homologous infection four months previously and with prior P. falciparum, but not P. vivax infection. There were no other indications that any Plasmodium species protected against heterologous infection. Prospective analysis of health-center morbidity supported the idea that P. malariae infection protects against disease, but indicated greater protection against non-malaria than P. falciparum-associated fevers. Plasmodium vivax appeared to protect against P. falciparum disease but not against other forms of morbidity. Covariate adjustment had considerable effects on estimated relationships between species, and confounding variables may account for many differences among reports of inter-species interactions in human malaria.     

Application of real-time polymerase chain reaction (PCR) analysis for detection and discrimination of malaria parasite species in Thai patients

A TaqMan real-time PCR system was used to detect and discriminate the 4 species of human malaria parasites in clinical blood samples. A 150-base pair (bp) region of the small subunit ribosomal RNA (SSU rRNA) gene of each malaria parasite, including species-specific sequences to be detected by TaqMan probe, was used as a target for PCR analysis. The PCR method used universal primers and species-specific TaqMan probes for Plasmodium falciparum, P. vivax, P. ovale, and P. malariae. The detection threshold for the method, as determined with serial dilution of cultured P. falciparum-infected erythrocytes, was 5 parasite-infected erythrocytes per reaction. Fifty blood samples of falciparum malaria and a second set of 50 samples of vivax malaria, diagnosed by microscopic examination at the Hospital for Tropical Diseases, Mahidol University, Thailand, were analyzed by real-time PCR. In the 50 samples of microscopically-diagnosed falciparum malaria, 40 were regarded as P. falciparum single infection, 7 were P. falciparum and P. vivax mixed infections, and 3 were P. vivax single infection by real-time PCR. In the second set of 50 samples of microscopically diagnosed vivax malaria, all were considered P. vivax single infection by PCR. Neither P. ovale nor P. malariae infection was identified in the 100 blood samples. Real-time PCR analysis was shown to be more sensitive and accurate than routine diagnostic methods. Application and extension of the PCR method reported here will provide a powerful tool for further studies of malaria.     

Imported non-Plasmodium falciparum malaria: a five-year prospective study in a European referral center

From 2000 to 2005, we investigated prospectively 98 cases of imported non-Plasmodium falciparum malaria (48 Plasmodium vivax, 34 P. ovale, and 16 P. malariae). Latency period between return and clinical attack exceeded three months in 40% of the patients. It was longer in travelers who had taken chemoprophylaxis. Time to diagnosis was longer in patients with P. malariae infection and in those with late-onset first attack. Parasite density was often lower than 500/microL, especially in P. ovale malaria. Relapses were diagnosed in 18% of all malaria episodes. Eight (17%) P. vivax and 2 (6%) P. ovale malaria episodes were due to relapse despite standard primaquine therapy. Diagnosis of imported non-falciparum malaria is often challenged by long latency period and low parasite density. In addition, the substantial relapse rate despite standard primaquine therapy supports the use of a higher dose of primaquine to eradicate P. vivax and P. ovale malaria effectively.     

Plasmodium brasilianum antigen for use in the indirect hemagglutination test.

Antigen was prepared from Plasmodium brasilianum harvested from an infected spider monkey. This antigen was attached to aldehyde-fixed, human type O cells, and was tested against sera from human cases of P. malaria, P. vivax, P. falciparum, and P. ovale infection, and sera from noninfected persons. At dilutions of 1:16 or greater the antigen failed to react in sera from noninfected persons. It reacted at titers of 16 or above with sera from 85% of the persons with P. malariae infection, 83% with P. vivax infection, 70% with P. falciparum infection, and 70% with P. ovale infection.     

Tumor necrosis factor-alpha in patients with malaria

Serum concentration of Tumor Necrosis Factor-alpha (TNF-alpha) was observed in 54 parasitologically confirmed cases of malaria. Of them, 15 cases were Plasmodium falciparum with cerebral involvement, three cases with mixed infections of P. falciparum and P. vivax, 32 cases of P. vivax, three cases of P. malariae and one case of P. ovale. Five out of 15 patients of P. falciparum (33.3 per cent), one out of 54 patients with mixed infection of P. falciparum and P. malariae (1.8 per cent) and the sole case of P. ovale (1.8 per cent) had fatal outcome. The serum TNF-alpha measured by avidin-biotin sandwich ELISA, was found to be significantly raised in P. falciparum and more so in fatal infections. The degree of parasitaemia, due to single or double infection, had positive effect on cytokine production. The mean TNF-alpha concentration was statistically significantly higher (p < 0.001) in P. falciparum than in P. vivax parasites infection. The mean TNF-alpha values in P. falciparum and P. vivax were 915 and 280.6 against the values in normal healthy controls of 12.9 pcg/ml respectively (p < 0.001). The study thus showed that the serum concentration of TNF-alpha correlated well with severity of malaria and these values could be used as an important prognostic marker of the disease.     

Evaluation of the Binax NOW ICT test versus polymerase chain reaction and microscopy for the detection of malaria in returned travelers

Microscopic detection of Plasmodium species has been the reference standard for the diagnosis of malaria for more than a century. However, maintaining a sufficient level of expertise in microscopic diagnosis can be challenging, particularly in non-endemic countries. The objective of this study was to compare a new rapid malaria diagnostic device (NOW ICT Malaria Test; Binax, Inc., Portland, ME) to polymerase chain reaction (PCR) and expert microscopy for the diagnosis of malaria in 256 febrile returned travelers. Compared with PCR, the NOW ICT test showed a sensitivity of 94% for the detection of P. falciparum malaria (96% for pure P. falciparum infection) and 84% for non-P. falciparum infections (87% for pure P. vivax infections and 62% for pure P. ovale and P. malariae infections), with an overall specificity of 99%. The Binax NOW ICT may represent a useful adjunct for the diagnosis of P. falciparum and P. vivax malaria in febrile returned travelers.     

2017年江苏省疟疾疫情特征分析

目的　掌握2017年江苏省疟疾疫情及流行特征,为制订和调整适合本省的消除疟疾后监测策略和措施提供依据。方法　对2017年全省网络报告疟疾疫情和专报系统的流行病学调查资料进行统计分析。 结果　2017年江苏省共报告疟疾239例,较2016年的308例下降22.40%。239例疟疾病例除2例为输血感染外,其余237例均为境外感染的输入性病例。239例疟疾病例中,恶性疟163例、间日疟21例、三日疟11例、卵形疟43例、恶性疟原虫与卵形疟原虫混合感染1例。2017年全省13个设区市均有疟疾病例报告,其中居前5位的为南通市（39例,16.32%）、苏州市（26例,10.88%）、泰州市（25例,10.46%）、淮安市（24例,10.04%）和连云港市（22例,9.21%）,5市合计报告的疟疾病例数占全省报告的疟疾病例总数的56.90%（136/239）。输入性疟疾报告病例的主要感染来源地为非洲（225例）、亚洲（8例）、大洋洲（2例）、南美洲（2例）,其中大洋洲和南美洲为新出现的感染来源地区。结论　江苏省连续6年无本地感染疟疾病例。2017年境外输入性疟疾病例虽较2016年有所下降,但仍是全省疟疾防控工作的重点。     

四川省输入性卵形疟原虫wallikeri亚种实验室检测分析

目的 鉴定四川省疑似输入性卵形疟原虫感染病例wallikeri亚种感染情况,并对2014-2017年全省1 079份复核血样卵形疟原虫wallikeri亚种感染情况进行分析。方法 对2018年1-4月四川省10例疑似输入性卵形疟原虫感染病例进行血涂片镜检、快速诊断试纸条（RDT）检测和巢式PCR检测并进行测序分析,同时回顾性检测2014-2017年全省 1 079份复核血样卵形疟原虫wallikeri亚种感染情况。结果 2018年1-4月四川省10例疑似输入性卵形疟原虫感染病例镜检结果均为卵形疟原虫阳性,其中2例存在恶性疟原虫混合感染;RDT检测结果均为疟原虫阳性;常规巢式PCR检测除2例结果为恶性疟原虫阳性外,其余均为阴性;采用卵形疟原虫wallikeri亚种特异性引物进行PCR检测,10例均为阳性,序列分析结果显示为卵形疟原虫wallikeri亚种。对2014-2017年全省1 079份复核血样进行回顾性检测,发现2例卵形疟原虫wallikeri亚种与恶性疟原虫混合感染病例,均为2017年报告,此前检测结果为单纯恶性疟原虫感染。结论 四川省首次鉴定发现输入性卵形疟原虫wallikeri亚种感染病例。     

2013年江苏省疟疾疫情流行病学分析

目的 目的 掌握江苏省2013年疟疾疫情及流行特征, 为制订和调整适合该省的消除疟疾策略和措施提供依据。 方 方 法 法 对2013年全省网络报告疟疾疫情和专报系统的流行病学调查资料进行统计分析。 结果 结果 2013年江苏省共报告疟 疾341例, 较2012年的198例上升72.22%, 发病率为0.050/万; 除1例为源于输入病例的输血感染外, 其余均为境外输入 病例。病例主要分布在连云港 （占15.84%, 54例）、 南通 （占14.08%, 48例）、 扬州 （占14.08%,48例）、 淮安 （占11.44%, 39 例） 和盐城 （占8.50%, 29例） 等5市。所有病例均经江苏省参比实验室确诊。其中, 恶性疟286例、 间日疟8例、 三日疟9 例、 卵形疟30例, 混合感染8例。 结论 结论 江苏省已连续2年无本地感染疟疾病例报告, 消除疟疾工作成效显著; 但境外感 染的输入疟疾病例日益增多, 且感染虫种呈多样性。境外输入疟疾仍是该省疟疾防控工作的重点。