Data_Sheet_4_Patterns of foot-and-mouth disease virus detection in environmental samples in an endemic setting.XLSX

Foot-and-Mouth Disease virus (FMDV) is endemic in several regions and is a virus that can persist in the environment dependent on pH, relative humidity (RH), temperature, and matrix (i.e., soil, water, or air). Our previously published analysis of available viral persistence data showed that persistence is likely affected by interactions between RH, temperature, and matrix. Understanding these relationships will aid efforts to eliminate FMD, which has significant impacts on economies and food security. In Cameroon, West Africa, the livestock system consists of mobile (transhumant), transboundary trade and sedentary herds. Studying this system can provide information about the patterns of environmental detection of FMDV RNA that may influence approaches to virus elimination on premises during an outbreak. To improve our understanding of these patterns, we collected samples from individuals, vehicles, and along cattle pathways at three sedentary herds beginning on day one of owner-reported outbreaks, ending by day 30, and tested for the presence of FMD viral RNA using rRT-PCR. Our analysis suggests that detection decreases in soil surface samples with increased distance from herd and time from the first report of disease. Whereas time but not distance decreases detection in air samples. Interaction of RH and temperature suggests increased detection at high temperatures (>24°C) and RH (>75%), providing us with new information about the patterns of FMD viral RNA detection in and around cattle herds that could help to inform targeted virus elimination strategies, such as location and application of disinfectants.

口蹄疫病毒（Foot-and-Mouth Disease Virus, FMDV）在多个区域呈地方性流行，是一种可在环境中存活的病毒，其存活时长依赖于pH值、相对湿度（Relative Humidity, RH）、温度以及基质（即土壤、水体或空气）。我们此前已发表的针对现有病毒存活数据的分析显示，病毒存活时长大概率受到相对湿度、温度与基质之间交互作用的影响。明晰这些关联将有助于推进口蹄疫（Foot-and-Mouth Disease, FMD）的根除工作，而该疫病会对经济与粮食安全造成严重影响。在西非喀麦隆，畜牧系统包含流动放牧（transhumant）、跨境贸易以及定居畜群三种模式。对该系统展开研究，可帮助我们了解口蹄疫病毒核糖核酸（FMDV RNA）的环境检出模式，这类模式或能影响暴发期间场区内的病毒根除策略。为加深对这类模式的理解，我们于畜主报告暴发后的第1天起至第30天结束前，在3个定居畜群中采集了个体样本、车辆样本以及牛只行进路径沿线样本，并通过实时逆转录聚合酶链式反应（real-time reverse transcription polymerase chain reaction, rRT-PCR）检测了口蹄疫病毒核糖核酸的存在情况。我们的分析结果显示，土壤表层样本的病毒检出率会随着与畜群的距离增大、距首次疫病报告的时间延长而降低；而空气样本的检出率仅随时间推移下降，与距离无关。相对湿度与温度的交互作用表明，在高温（>24℃）且高湿度（>75%）的环境下，病毒检出率会升高。这为我们提供了牛群内外口蹄疫病毒核糖核酸检出模式的新信息，可用于指导针对性的病毒根除策略，例如消毒剂的布设点位与使用方案。