ABSTRACT: Vibrio aestuarianus infection in oyster populations causes massive mortality, resulting in losses for oyster farmers. Such dynamics result from host-pathogen interactions and contagion through water-borne transmission. To assess the spatiotemporal spread of V. aestuarianus infection and associated oyster mortality at a bay scale, we built a mathematical model informed by experimental infection data at 2 temperatures and spatially dependent marine connectivity of oyster farms. We applied the model to a real system and tested the importance of each factor using a number of modelling scenarios. Results suggest that introducing V. aestuarianus in a fully susceptible adult oyster population in the bay would lead to the mortality of all farmed oysters over 6 to 12 mo, depending on the location in which infection was initiated. The effect of temperature was captured by the basic reproduction number (R₀), which was >1 at high seawater temperatures, as opposed to values <1 at low temperatures. At the ecosystem scale, simulations showed the existence of long-distance dispersal of free-living bacteria. The western part of the bay could be reached by bacteria originating from the eastern side, though the spread time was greatly increased. Further developments of the model, including the consideration of the anthropogenic movements of oysters and oyster-specific sensitivity factors, would allow the development of accurate maps of epidemiological risks and help define aquaculture zoning.

中文翻译：

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河口弧菌感染的空间流行病学模型表明，连通性和温度控制牡蛎死亡率

摘要：牡蛎种群中的河口弧菌感染导致大量死亡，给牡蛎养殖者造成损失。这种动态是由于宿主与病原体之间的相互作用以及通过水传播的传染所导致的。为了评估海湾规模上的河口沙门氏菌感染的时空传播和相关牡蛎死亡率，我们建立了一个数学模型，该模型由2个温度下的实验感染数据以及牡蛎养殖场的空间相关海洋连通性决定。我们将模型应用于实际系统，并使用多种建模方案测试了每个因素的重要性。结果表明，引入了V. aestuarianus在海湾中一个完全易感的成年牡蛎种群，将导致所有养殖牡蛎的死亡超过6到12个月，这取决于开始感染的地点。温度的影响可以通过基本再现数（R ₀），在较高的海水温度下为> 1，而在低温下为<1。在生态系统范围内，模拟表明存在自由生存细菌的远距离扩散。尽管传播时间大大增加，但从东部传播的细菌仍可到达海湾的西部。该模型的进一步发展，包括考虑牡蛎的人为运动和牡蛎特有的敏感性因素，将有助于开发准确的流行病风险图，并有助于确定水产养殖区划。