Risk of sexual transmission of Zika virus infection: a study among sex workers and their clients in an endemic area of coastal Ecuador

寨卡病毒(ZIKV)是一种通过伊蚊叮咬传播给人类的黄病毒，最近于2015年在美洲流行。目前还没有ZIKV的疫苗或治疗方法。在大约80%的感染者中，寨卡病毒无症状，有症状的病例表现为轻度发热。然而，在目前的拉丁美洲疫情期间，同时报告受感染孕妇的严重神经系统并发症和不良胎儿结局成为令人担忧的原因。ZIKV现在被认为与新生儿小头畸形症有因果关系，原因不明，这可能是拉丁美洲发病率地区差异的原因。除了经典的传播之外，很明显ZIKV遵循埃博拉的脚步。病毒在感染后持续存在于精液和外阴阴道液中，在没有经典蚊子传播途径的情况下，人与人之间发生性传播的病例越来越多。如果性传播被证明是一种既定的传播途径，单靠灭蚊力量可能不足以在有能力传播媒介的地区遏制寨卡病毒从零星流行向可持续流行的转变。该项目将初步确定厄瓜多尔埃斯梅拉达斯省奎宁德地区在性传播感染高危人群中寨卡病毒的基线血清阳性率。将招募女性性工作者，并对该地区流行的寨卡病毒和其他蚊媒病毒进行血清学筛查。来自性工作者人群的样本将与昆宁德公立医院产前诊所就诊的育龄妇女的年龄和性别匹配的对照组样本进行比较，以确定那些有高风险性行为的人是否有更高的ZIKV患病率，以估计性传播对整体ZIKV负担的可能贡献。参与者还将接受问卷调查，收集有关人口、社会经济和生活方式信息(包括敏感的性行为和其他高风险行为，如一贯使用避孕套、生殖器外性行为和非法药物使用)的信息。2这个博士项目涉及医学研究理事会制定的所有四个战略目标的各个方面(医学研究理事会，研究改变生活，医学研究理事会战略计划2014-2019https://www.mrc.ac.uk/publications/browse/strategic-plan-2014-19/).Strategic目标1：交付的研究；主题二“健康长寿”和战略目标2：对人民进行研究评估性传播的风险因素，随后向目标群体提供信息，对高危人群进行教育/筛查，并提高对ZKV周围的公共卫生意识。战略目标3：走向全球通过在厄瓜多尔的伙伴实验室内开展工作，我们的项目不仅促进了伦敦圣乔治大学、MRC LID方案和(厄瓜多尔)国际大学之间的合作，而且还在厄瓜多尔国内建立了能力。该项目的结果有可能支持在一个节育和避孕套尚未广泛获得或使用的国家倡导女性和性工作者的性健康和权利。能力和技能学生将接受以下方面的培训；定量技能流行病学调查问卷的创建和分析分子、基因组和系统发育技术跨学科技能与社会和定性科学家合作制定问卷和具有社会/社会活力的项目协议与实验室科学家合作开发分子和基因组技能与厄瓜多尔当地环境合作开发现场流行病学和西班牙语杀手全球生物生理学了解寨卡病毒在患者体内的感染动力学ZIKV基因组分析以了解寨卡病毒的症状和生物学表现

Zika Virus (ZIKV) is a flavivirus transmitted to humans through the bite of Aedes mosquitoes, recentlyepidemic in the Americas in 2015. There is currently no vaccine or treatment for ZIKV. ZIKV isasymptomatic in approximately 80% of those infected, with symptomatic cases displaying mild febrileillness. However, during the ongoing Latin America epidemic, concurrent reporting of severeneurologic complications and adverse foetal outcomes in infected pregnant women became cause forconcern. ZIKV is now considered causally linked to microcephaly in new-borns with unknown cofactorsperhaps accounting for regional variation in incidence in Latin America.In addition to classic transmission, it has become apparent that ZIKV follows in the footsteps of Ebola.Virus is persistent in semen and vulvovaginal fluids post-infection, with increasing numbers of casereports of sexual transmission between humans in the absence of classical mosquito transmissionpathways. If sexual transmission proves to be an established transmission route, mosquito controlefforts alone may not be enough to curb the transition of ZIKV from sporadic epidemic to sustainedendemicity in regions with capable vectors.The project will initially determine the baseline seroprevalence of ZIKV in the District of Quininde,Esmeraldas Province, Ecuador among high-risk groups for STIs. Female sex workers will be recruitedand serologically screened for ZIKV, and other mosquito borne viruses endemic to the region. Samplesfrom sex worker populations will be compared to those of an age and gender-matched control group ofwomen of childbearing age attending antenatal clinics at the public hospital in Quininde, to determine ifthere is a higher prevalence of ZIKV in those with 'high' risk sexual behaviours to estimate the possiblecontribution of sexual transmission to overall ZIKV burden. Participants will also be administered aquestionnaire collecting information on relevant demographic, socioeconomic and lifestyle information(including sensitive sexual and other high risk behaviours such as consistency of condom use, extragenitalsex and illicit drug use). 2This PhD project addresses aspects of all four Strategic Aims laid out by the Medical Research Council(MRC, Research Changes Lives, MRC Strategic Plan 2014-2019https://www.mrc.ac.uk/publications/browse/strategic-plan-2014-19/).Strategic Aim 1: Research that Delivers; Theme Two "Living a Long and Healthy Life" ANDStrategic Aim 2: Research to the peopleAssessment of risk factors for sexual transmission, subsequently informing targetededucation/screening of high-risk groups, as well as enhancing public health awareness effortssurrounding ZIKV.Strategic Aim 3: Going GlobalBy working within partner laboratories in Ecuador, our project not only fosters collaborationbetween St George's University London, the MRC LID programme and the InternationalUniversity (of Ecuador), but also builds capacity within Ecuador.The findings of this project have the potential to support advocacy for female and sex workersexual health and rights in a country, where birth control and condoms are not widely availableor used.Strategic Aim 4: Supporting Scientists, Capacity and SkillsThe student will undergo training in the following areas;Quantitative SkillsEpidemiological questionnaire creation and analysisMolecular, genomic and phylogenetic techniquesInterdisciplinary SkillsCollaboration with social and qualitative scientists to develop questionnaires andethically/socially robust project protocolsWorking with laboratory scientists to develop molecular and 'omic skillsWorking with local settings in Ecuador to develop field epidemiology and Spanish languageskillsWhole Organism PhysiologyDeveloping an understanding of ZIKV infection kinetics within patientsZIKV genomic analysis to understand symptomatic and biological presentation of ZIKV