Immune Responses to Vibrio cholerae infection and vaccination in Haiti

描述(申请人提供)：海地目前的霍乱疫情是过去十年中最大的疫情之一，代表着日益严重的霍乱疫情负担。值得注意的是，在免疫水平较低的人群中，以及在亚洲历史上霍乱流行地区以外的人群中，对霍乱和口服霍乱疫苗的免疫反应知之甚少。最重要的是，所有关于使用霍乱疫苗的决定都是根据在世界上霍乱长期根深蒂固的地区产生的免疫原性和效力数据做出的，在这些地区，霍乱疫苗可能会增强以前接触过的个人的记忆免疫反应。因此，在海地推广Shanchol期间对疫苗免疫原性和有效性的评估提供了直接为疫苗战略提供信息的独特机会。对艾滋病毒和霍乱之间的关系几乎一无所知，尽管向世卫组织报告的霍乱病例数量最多的现在来自撒哈拉以南非洲。在这里，我们建议描述海地对口服霍乱疫苗和霍乱弧菌感染的免疫反应--海地以前的免疫水平很低，宿主和流行病学特征反映了近年来经历霍乱流行的人群。我们还直接评估了海地口服霍乱疫苗Shanchol的效力，并评估了艾滋病毒和霍乱弧菌感染与疫苗接种之间的相互关系。我们的合作小组深入参与了海地霍乱疫苗的推出，并处于执行拟议研究的独特位置。

DESCRIPTION (provided by applicant): The ongoing epidemic of cholera in Haiti is one of the largest of the last decade and is representative of a growing burden of epidemic cholera. Remarkably little is known about immune responses to cholera and oral cholera vaccines in immunologically na¿ve populations, and in populations outside of historically cholera endemic areas of Asia. Of paramount importance, all decisions regarding the use of cholera vaccine have been made using immunogenicity and efficacy data generated in areas of the world where cholera has long been entrenched and where cholera vaccine may be boosting anamnestic immune responses in previously exposed individuals. Therefore, assessment of vaccine immunogenicity and effectiveness during the roll out of Shanchol in Haiti provides the unique opportunity to directly inform vaccine strategies. Almost nothing is known about the relationship between HIV and cholera, despite the fact that the largest number of cholera cases reported to WHO are now from Sub-Saharan Africa. Here, we propose to characterize immune responses to oral cholera vaccines and to V. cholerae infection in Haiti -- a previously immunologically na¿ve population with host and epidemiologic features that are reflective of populations experiencing cholera epidemics in recent years. We also directly assess the efficacy of the oral cholera vaccine, Shanchol, in Haiti, and evaluate the inter-relationship between HIV and V. cholerae infection and vaccination. Our collaborative team is deeply involved in the cholera vaccine roll-out in Haiti and is uniquely situated to perform the proposed studies.