Marine diseases have major impacts on ecosystems and economic consequences for aquaculture and fisheries. Understanding origin, spread and risk factors of disease is crucial for management, but data in the ocean are limited compared to the terrestrial environment. Here we investigated how the marine environment drives the spread of viral disease outbreak affecting The Pacific oyster worldwide by using a spatial epidemiology framework. We collected environmental and oyster health data at 46 sites spread over an area of 300 km² along an inshore-offshore gradient during an epizootic event and conducted risk analysis. We found that disease broke out in the intertidal farming area and spread seaward. Mortalities and virus detection were observed in oysters placed 2 km from the farming areas, but oysters of almost all sites were subclinically infected. Increasing food quantity and quality, growth rate and energy reserves of oyster were associated with a lower risk of mortality offshore whereas increasing turbidity, a proxy of the concentration of suspended particulate matter, and terrestrial inputs, inferred from fatty acid composition of oysters, were associated with a higher risk of mortality. Offshore farming and maintenance of good ecological status of coastal waters are options to limit disease risk in oysters.

中文翻译：

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使用大规模空间流行病学框架确定牡蛎疱疹病毒暴发的危险因素。

海洋疾病对生态系统有重大影响，并对水产养殖和渔业产生经济影响。了解疾病的起源，传播和危险因素对于管理至关重要，但是与陆地环境相比，海洋中的数据是有限的。在这里，我们通过空间流行病学框架研究了海洋环境如何驱动病毒性疾病爆发的传播，从而影响了太平洋牡蛎在世界范围内。我们收集了分布在300 km ^2内的46个站点的环境和牡蛎健康数据在流行期间发生沿岸-离岸梯度的变化，并进行了风险分析。我们发现该病在潮间带农业区爆发并向海传播。在距养殖区2公里处的牡蛎中观察到死亡率和病毒检测，但几乎所有地点的牡蛎都受到亚临床感染。从牡蛎的脂肪酸组成推断出，牡蛎的食物数量和质量，生长速度和能量储备的增加与较低的离岸死亡率相关，而浊度增加，悬浮颗粒物浓度和地面投入的相关性增加具有更高的死亡风险。海上养殖和维持沿海水域良好的生态状况是限制牡蛎疾病风险的选择。