Pathways Of Dispersal for Cholera And Solution Tools (PODCAST)

霍乱是一种水传播的人类流行病。它是一个重大的公共卫生威胁，每年影响全世界130万至400万人，据报告死亡21 000至143 000人。霍乱暴发是由霍乱弧菌病原菌引起的，在世界各地的许多沿海、河口和咸淡水中都有发现。当前霍乱大流行的起源是印度洋东北部盆地的单一病原体种群，在几次传播事件中向全球传播。传播途径包括人与人之间的直接感染和人与环境的相互作用，包括摄入受污染的水，而抗生素释放到环境中而出现的抗菌素耐药性加剧了这种相互作用。弧菌病原体以自由漂浮的形式存在，或附着在生物（浮游生物）和非生物（沉积物）宿主上。它们在温暖的温度、适度的盐度和浑浊度下繁殖。弧菌的主要环境宿主、它们的连通性、它们如何受到气候变化的影响以及对人类健康的相关影响在很大程度上仍然未知。显然，必须减少人类感染霍乱菌的风险，以实现与3-人类健康、6-水质、13-气候和14-水下生命有关的全球目标。目前印度洋北部是霍乱和相关疾病爆发的温床，播客项目将重点关注该地区，查明大规模海洋和气候过程对霍乱传播动态的影响（目标6、13、14）及其对公共卫生的影响（目标3）。来自印度、日本和英国的科学家将合作开展以下工作：1)确定霍乱弧菌的环境宿主以及可能通过洋流的平流运输和霍乱疫情的远距离传播途径；2)描述气候扰动对霍乱暴发和环境传播途径的影响；3)建立整合环境和人际传播途径的流行病学模型；4)对沿海地区的霍乱疫情进行预测。这项研究将与最终用户协商进行，包括依靠水资源维持生计、创收和娱乐的当地社区；政府;卫生服务;政府间机构;以及政策制定者，我们将为他们提供工具和弧菌疾病风险地图产品，以支持基于证据的政策决策和行动，以实现全球目标。这项工作将分为四个工作包。WP1 （abdulaziz -印度；sathyendranath -英国）将在公海和沿海地区的选定地点对生物物理变量（包括弧菌病原体和抗生素）进行新的现场观测；并处理整个北印度洋的卫星数据（海洋颜色、盐度、高度计和温度）。WP2 （Platt-UK; Clark-UK; Nonaka-Japan）将侧重于模型并使用来自WP1的数据，开发一个流行病学模型，包括霍乱疫情的人际传播和环境传播途径的组成部分；粒子跟踪模型用于研究弧菌的来源和环境水库之间的连通性；以及一个气候变率模式，用于生成大尺度气候变率模式的过去和未来指数。基于环境条件、区域环流和气候变率对北印度洋沿海地区暴发风险的影响（WP 2）的WP3 （Racault-UK）将侧重于为北印度洋沿海地区建立一个霍乱暴发预测系统。用户参与、政策信息和实践干预措施将在第四次世界行动计划（Menon-India; George-India）中讨论，我们将与当地社区、决策者和政府间机构（世卫组织、IPCC）接触，以确定需求、评估效益、最佳做法和吸收播客成果，以减少弧菌疾病对公共卫生的风险。

Cholera is a waterborne epidemic disease in humans. It is a major public health threat, affecting 1.3 to 4 million people each year worldwide, with 21,000 to 143,000 reported fatalities. Outbreaks are caused by the bacterial pathogen Vibrio cholerae, found in many coastal, estuarine, and brackish waters around the world. The origin of the current pandemic of cholera was a single population of pathogens in the north-eastern Indian Ocean basin, which spread globally, in several transmission events. Transmission pathways include direct human-to-human infection, and human-environment interactions, including ingestion of contaminated water, aggravated by emerging antimicrobial resistance through release of antibiotics into the environment. Vibrio pathogens are found as free-floating forms or attached to living (plankton) and non-living (sediment) hosts. They flourish under warm temperature, moderate salinity and turbidity. The major environmental reservoirs of Vibrios, their connectivity, how they might be affected by climate variability and the associated impact on human health remain largely unknown. There is a clear imperative to reduce human risk from cholera bacteria to meet Global Goals related to 3-human health, 6-water quality, 13-climate and 14-life under water. Focusing on the northern Indian Ocean, currently a hotbed of outbreaks of cholera and related diseases, the PODCAST project will pinpoint the impact of large-scale oceanic and climatic processes on the transmission dynamics of cholera (Goals 6, 13, 14) and their impact on public health (Goal 3). Scientists from India, Japan and the UK will work collaboratively to: 1) identify environmental reservoirs of Vibrio cholerae as well as possible advective transport via ocean currents and long-distance transmission routes for cholera outbreaks; 2) characterise the influence of climate perturbations on cholera outbreaks and environmental transmission routes; 3) build an epidemiological model integrating environmental and human-to-human transmission routes; and 4) produce forecasts for cholera outbreaks in coastal regions. The research will be developed in consultation with end-users, including local communities relying on water resources for livelihoods, income generation and recreation; governments; health services; intergovernmental agencies; and policy makers for whom we will provide tools and Vibrio disease risk map products that will support evidence-based policy decisions and actions to achieve Global Goals.The work will be organised in four Work Packages. WP1 (Abdulaziz-India; Sathyendranath-UK) will generate new in situ observations of biophysical variables (including Vibrio pathogens and antibiotics) at selected sites in open-ocean and coastal locations; and process satellite data (ocean-colour, salinity, altimeter and temperature) over entire northern Indian Ocean. WP2 (Platt-UK; Clark-UK; Nonaka-Japan), focussing on models and using data from WP1, will develop an epidemiological model including components of human-to-human and environmental transmission routes of cholera outbreaks; a particle-tracking model to study sources and connectivity between environmental reservoirs of Vibrios; and a climate-variability model to generate past and future indices of large-scale patterns of climate variability. WP3 (Racault-UK), based on the influence of environmental conditions, regional circulation and climate variability on risks of outbreaks at coastal locations in the northern Indian Ocean (WP 2), will focus on producing a cholera-outbreak prediction system for coastal regions of the northern Indian Ocean. The user-engagement, policy information and practice interventions will be addressed in WP4 (Menon-India; George-India) in which we will engage with local communities, policy-makers, and intergovernmental agencies (WHO, IPCC) to identify needs, assess benefits, best practices and uptake of results from PODCAST to reduce risks of Vibrio diseases to public health.