北京市寨卡病毒病输入疫情处置及经验探讨

目的 描述北京市输入寨卡病毒病的流行病学特征和疫情防控措施,为寨卡病毒病等蚊传疾病防控提供参考依据.方法 对患者进行流行病学调查,采集患者尿液、唾液和血液标本,使用实时荧光PCR方法对标本进行寨卡病毒核酸检测.防控措施包括病例的防蚊隔离、污染物品消毒和防控知识宣教.结果 麻疹样皮疹是这3名患者共有的主要症状,患者同时伴有低热和结膜炎.3例病例均在委内瑞拉首都加拉加斯被蚊虫叮咬后感染发病,并分别于发病后1日、3日和7日从北京入境.患者入境时主动向检疫部门申报,随后被防蚊隔离并人院治疗.实时荧光PCR检测3名患者尿液标本寨卡病毒核酸均为阳性.结论 3例输入寨卡病毒病病例经早期诊断治疗均痊愈出院,防蚊隔离措施和性传播知识的宣教是预防该病在国内的传播、有效防止出现二代病例的有效措施.相关措施将对今后输入寨卡病毒病和其他蚊传疾病的防控有所裨益.     

中国首例输入性裂谷热病例的流行病学调查

目的 描述中国首例输入性裂谷热病例的发病就诊过程、流行病学特征和疫情处理过程,以期对输入性裂谷热病例的管理有所启示.方法 对该患者开展现场流行病学调查.采集患者的血液和唾液标本,应用实时荧光PCR方法对患者标本开展黄热病和裂谷热病毒核酸检测.结果 患者男,45岁,2016年7月14日晚在安哥拉出现发热、头痛等症状,症状持续加重.7月21日22:30患者抵京.抵京后,患者到北京市一传染病专科医院住院治疗,当日经北京市疾病预防控制中心检测患者为裂谷热病毒核酸阳性.经治疗,患者病情好转.9月6日患者治愈出院.结论 该患者为我国首例输入性裂谷热病例.病例在安哥拉工作期间被蚊虫叮咬感染裂谷热.我国与疫情发生国存在持续的人员往来,应加强入境病例排查,做到病例早发现、早隔离,降低出现续发病例的可能性.     

中国内地寨卡病毒病输入传播风险评估研究

2016年全球寨卡病毒病疫情暴发,使我国面临一定的输入传播风险。本研究基于2016年全球寨卡病毒病报告疫情数据、全球国际航班客流量数据和我国云南和广西边境口岸分布等数据,通过计算输入风险指数评估我国主要城市寨卡病毒病输入风险。应用生态位模型预测中国当前埃及伊蚊、白纹伊蚊的分布区域,结合内地主要城市寨卡病毒病输入风险指数、埃及伊蚊或白纹伊蚊的分布概率等数据,计算主要城市寨卡病毒病输入后继发本地传播风险指数,评估本地传播风险。研究表明北京、上海和广州经国际航班输入寨卡病毒病的风险高;云南省德宏州、临沧市和西双版纳州以及广西防城港市和北海市经陆运口岸输入的风险较高;需加强口岸检疫,及时发现病例。仅考虑埃及伊蚊在该病传播中发挥作用,海口、三亚和湛江存在寨卡病毒病本地传播风险。云南省德宏州、临沧市两地在3-11月份如发生陆运口岸输入寨卡病毒病,存在经埃及伊蚊引起本地传播的中等风险。这些城市需要加强人群和伊蚊的监测,以利于早发现疫情、及早采取防蚊灭蚊等防控措施。     

昆明市登革热输入性病例的调查及C/PreM基因序列分析

目的 调查云南省昆明市登革热输入性病例分布状况及病原分子特征.方法 收集登革热病例资料,采集本病急性期病人血清标本,用ELISA法检测登革病毒(DENV) IgM抗体,RT-PCR法检测DENV核酸,核酸阳性者进行DENV-C/PreM区的基因核苷酸序列测定和分析,采用MEGA5软件的邻接法构建进化树.结果 2010-2013年在昆明市第三人民医院住院病人中采集到登革热临床诊断病例血清标本13份,经检测DENV-IgM抗体均为阳性,DENV核酸阳性2份.根据流行病学史、临床表现和实验室检测结果,这13例病人均被诊断为登革热.获得了两株病毒(YNH8和YNH12)的C/PreM区基因核苷酸序列,进化分析表明YNH8和YNH12株均为登革Ⅰ型病毒.其中YNH8株与南亚地区印度流行株进化关系最为接近,而YNH12株与泰国、缅甸、柬埔寨和越南等东南亚国家流行株具有较近亲缘关系.结论 昆明市登革热患者均为输入性病例.流行病学史和分子流行病学研究证实,YNH8和YNH12病例与印度和缅甸流行株具有较近亲缘关系.     

寨卡病毒研究进展

寨卡病毒是一种主要由伊蚊传播的蚊媒病毒,感染该病毒后的主要症状包括低热、斑丘疹、关节疼痛、结膜炎等,并且有造成神经和自身免疫系统并发症的风险,孕妇感染寨卡病毒常导致新生儿小头畸形。目前寨卡病毒有全球扩散风险。本文就寨卡病毒病的流行病学、临床研究、传播媒介以及防控等研究现状进行综述,以期对寨卡的防治提供借鉴。     

上海市668例输入性疟疾病例流行病学分析

目的了解和掌握上海市疟疾的流行特征。方法对2003-2008年上海市输入性疟疾病例的流行病学特征进行分析。结果 2003-2008年期间共有668例输入性疟疾病例,占全部疟疾病例的85.97%,其中间日疟482例、恶性疟42病例、疟疾（未分型）144例。病例分布于全市19个区县;发病季节呈全年分布;男女性别比为2.16∶1;年龄在1～81岁间;职业主要为民工和学生。感染来源地主要为安徽等周边省市疟疾流行地区和非洲等国外疟疾高发区。结论输入性疟疾病例是本市疟疾的主要疫情特点,病例感染来源地主要为安徽等周边省市疟疾流行地区和非洲等国外疟疾高发区。     

中国虫媒病毒病的发现,临床表现与流行概况

中国虫媒病毒病的发现、临床表现与流行概况李其平，郅琦（新疆维吾尔自治区地方病防治研究所，乌鲁木齐８３０００２）虫媒病毒病（Ｄｉｓｅａｓｅｏｆａｒｂｏｖｉｒｕｓ）是一组种类较多的病毒性疾病，又称人畜共患病毒性疾病（ｖｉｒａｌｚｏｏｎｏｓｅｓ）。属于自然...     

2009年广州市2例输入性登革热病例的调查

目的了解2009年广州市2例输入性登革热病例的流行病学、病原学检查特点。方法对患者及密切接触者流行病学及临床资料进行回顾性分析,采用免疫层析法、ELISA法对患者血清样本进行登革热IgM、IgG抗体检测,并采用PCR对病毒进行分型。结果两名患者均来自登革热疫区,出现乏力、发热、头痛等症状。患者的DEV-IgM均呈阳性,DEV-IgG呈阴性,病毒型别均为登革Ⅰ型。结论两名患者为实验室确诊病例,由于发现及时,患者救治方案正确,各项防控措施落实到位,2例患者均痊愈出院,未发生二代病例,疫情得到有效控制。     

北京市首例人感染H9N2禽流感病例的流行病学调查

目的 分析2016年12月北京市朝阳区确诊的l例人感染H9N2禽流感病例流行病学特征.方法 访谈病例发病前后的相关知情人,调查病例发病经过和可能感染来源.采集病例、密切接触者及环境标本,应用实时荧光定量PCR(real-timePCR)方法,检测甲型流感病毒及H9N2禽流感病毒特异的核酸片段.对病例咽拭子标本和l件阳性环境标本中的H9N2禽流感病毒血凝素(Hemagglutinin,HA)基因进行序列测定和分析.结果 病例表现为轻症流感样病例症状,发病前15天曾有活禽市场暴露史.该市场环境标本中H9N2禽流感病毒阳性率为18.2％ (2/11).病例咽拭子标本与市场环境标本中病毒的HA基因高度同源,氨基酸相似度为100％,在进化关系上同属于欧亚系的Y280分支.4名密切接触者在医学观察期内未出现过发热、咳嗽等呼吸道症状.结论 病例感染来源与活禽市场环境暴露有关.加强流感监测以及活禽市场的管理对于防控人感染禽流感疫情具有重要意义.     

广州增城市一起输入性登革热暴发的流行病学调查分析

目的分析广州增城市2006年一起输入性登革热暴发的流行病学特征，为制定预防控制措施以及在暴发疫情中进行索源调查提供科学依据。方法采用流行病学调查和回顾性病例搜索，对该起登革热疫情调查分析；采用间接免疫荧光法对病例血清进行登革热抗体检测；用布雷图指数（BI）进行蚊媒密度调查。结果病例刘某为实验室确诊病例，无外出史；索源调查发现的病例黄某及其侄子血清登革热IgM、IgG均阳性，有疫区活动史，发病时间与刘某发病在一个潜伏期内。结论该病例为增城市2006年首例报告登革热确诊的本地感染病例，感染来源为区外输入性；早期被误诊，传染源未被及时发现是导致本次疫情的重要原因；迅速灭蚊和消除伊蚊孳生地是控制疫情的有效措施；多部门参与、组织专业队及时扑救疫情是迅速控制登革热流行的幸兽原因．     

Zika virus infection of Hofbauer cells

Recent studies have linked antenatal infection with Zika virus (ZIKV) with major adverse fetal and neonatal outcomes, including microcephaly. There is a growing consensus for the existence of a congenital Zika syndrome (CZS). Previous studies have indicated that non‐placental macrophages play a key role in the replication of dengue virus (DENV), a closely related flavivirus. As the placenta provides the conduit for vertical transmission of certain viruses, and placental Hofbauer cells (HBCs) are fetal—placental macrophages located adjacent to fetal capillaries, it is not surprising that several recent studies have examined infection of HBCs by ZIKV. In this review, we describe congenital abnormalities associated with ZIKV infection, the role of HBCs in the placental response to infection, and evidence for the susceptibility of HBCs to ZIKV infection. We conclude that HBCs may contribute to the spread of ZIKV in placenta and promote vertical transmission of ZIKV, ultimately compromising fetal and neonatal development and function. Current evidence strongly suggests that further studies are warranted to dissect the specific molecular mechanism through which ZIKV infects HBCs and its potential impact on the development of CZS.     

Confirmed Zika virus infection in a Belgian traveler returning from Guatemala,and the diagnostic challenges of imported cases into Europe

We report the first laboratory-confirmed Zika virus (ZIKV) infection in a Belgian traveler after a three week holiday in Guatemala, December 2015. This case along with other imported cases into Europe emphases once again the need for accurate diagnostic tools for this rapidly emerging virus. The challenge is to diagnose patients in the acute phase, which appears short, as serological testing is complicated by cross-reactivity, vaccination status and scarce availability of specific ZIKV tests.     

Detection of Zika virus in saliva

BackgroundDuring the largest Zika virus (ZIKV) outbreak ever reported that occurred from October 2013 to March 2014 in French Polynesia, we observed that several patients presenting the symptoms of acute phase Zika fever were tested negative in blood by ZIKV real-time PCR (RT-PCR).ObjectivesAs we have previously detected ZIKV RNA in the saliva of a young child, we investigated the use of saliva as an alternative sample for routine ZIKV RNA detection.Study designOver a 6 month period, 1,067 samples collected from 855 patients presenting symptoms of Zika fever (saliva only, blood only or both samples) were tested using a specific ZIKV RT-PCR. A medical questionnaire was available for most of the patients.ResultsZIKV was more frequently detected in saliva compared to blood. For the 182 patients with both samples collected, tests were positive for 35 (19.2%) in saliva while negative in blood and tests were positive for 16 (8.8%) in blood while negative in saliva; the difference in mean days after symptoms onset and the percentage of the main symptoms of Zika fever for patients only positive in saliva or in blood was not significant.ConclusionThe use of saliva sample increased the rate of molecular detection of ZIKV at the acute phase of the disease but did not enlarge the window of detection of ZIKV RNA. Saliva was of particular interest when blood was difficult to collect (children and neonates especially).     

A case of Mayaro virus infection imported from French Guiana

Emergence of arboviruses is a rising problem in several areas in the world. Here we report a case of Mayaro virus infection that was diagnosed in a French citizen presenting a dengue-like syndrome with prolonged arthralgia following a travel in French Guiana. Diagnosis was based on serological testing, a newly developed specific RT–PCR and sequencing.The real incidence of this viral infection among travelers is poorly known but this case is the first reported in a European area where Aedes albopictus mosquitoes are established, which underscores the necessity to determine the vector competence of the European strain of this mosquito species for Mayaro virus.     

An updated review of Zika virus

The current outbreak of Zika virus (ZIKV) in South America is one of the most serious public health emergencies since the Ebola outbreak of West Africa [2014]. ZIKV belongs to the flaviviridae family and has two lineages (Asian and African). The virus was first discovered in Uganda [1947] and the first human infection was identified in Nigeria [1952]. The current epidemic is the third of its type after that of Yap Island, Micronesia [2007] and French Polynesia [2013]. Phylogenetic studies revealed that the current strain shares about 99.7% of nucleotides and 99.9% of amino acids with the strain of French Polynesia epidemic [2013], suggesting that it has spread across the Pacific Ocean to invade South America. Aedes Aegypti mosquito is the main vector for ZIKV and there are some reports describing possible sexual and maternal to fetal transmission. ZIKV infection is known to be self-limited. However, recent reports suggested that it can be associated with neurological manifestations as Guillan-Barrè Syndrome and microcephaly in the newborn population. Currently, vector control seems to be the most effective available preventive measure against ZIKV spread. The development of broad spectrum antivirals and ZIKV vaccines should be a priority of future research.     

Zika virus infections imported to Italy: Clinical,immunological and virological findings,and public health implications

We report the first two cases of laboratory confirmed Zika virus (ZIKV) infections imported into Italy from French Polynesia. Both patients presented with low grade fever, malaise, conjunctivitis, myalgia, arthralgia, ankle oedema, and axillary and inguinal lymphadenopathy. One patient showed leukopenia with relative monocytosis and thrombocytopenia.The diagnosis was based on ZIKV seroconversion in both cases and on ZIKV RNA detection in one patient from acute serum sample. Sera from both patients exhibited cross-reactivity with dengue virus antigens. Our immunological analysis demonstrated that recovery from ZIKV infection is associated with restoration of normal numbers of immune cells in the periphery as well as with normal function of antigen-presenting cells. ZIKV is an emerging arbovirus, which has recently spread extensively in tourist destinations on several West Pacific islands. Returning viremic travelers may ignite autochthonous infections in countries like Italy, which are infested by Aedes albopictus, a suitable vector for ZIKV. The role of clinicians is crucial and includes early diagnosis and timely notification of public health authorities in order to quickly implement adequate focal vector control measurements.     

Two cases of thrombocytopenic purpura at onset of Zika virus infection

We report here two cases of thrombocytopenic purpura at onset of Zika virus infection. A 26-year-old woman and a 21-year-old man had thrombocytopenia above 5 × 10⁹ platelets/L. Hemorrhagic symptoms were mucosal and subcutaneous bleeding and gross hematuria and they reported episode of conjunctivitis. In both cases blood and bone marrow analysis suggested thrombocytopenic purpura, blood PCR tests for Dengue (DENV), Chikungunya (CHIKV) and Zika virus (ZIKV) were negative. In both cases urinary PCR for ZIKV was positive, Prednisolone yielded early remission. Only three similar cases have been reported so far. In the Caribbean, DENV is also epidemic and responsible for severe thrombocytopenia. Coinfections can occur. Our report underlines the need to include a ZIKV assay in the diagnostic work-up of thrombocytopenic purpura in epidemic areas.