Department of Veterinary Surgery, College of Veterinary Medicine, Northeast Agricultural University, Harbin, China.
College of Wildlife and Protected Area, Northeast Forestry University, Harbin, China.
Transbound Emerg Dis. 2021 Mar;68(2):445-457. doi: 10.1111/tbed.13695. Epub 2020 Jul 12.
Rift Valley fever (RVF) is a mosquito-borne zoonotic disease. Since its first outbreak in 1930, RVF epidemics have caused huge economic losses and public health impacts in Africa. In 2000, RVF became a disease of global concern as it spread to the Arabian Peninsula. In our study, a Geographic Information System-based risk assessment for the occurrence of Rift Valley fever in China was established by means of ecological niche modelling. Based on occurrence records (RVF records from FAO EMPRES-i, vector records from literatures and GBIF) and high-resolution environmental layers, the prediction maps of RVF occurrence probability and distribution of five potential RVF vectors in China were modelled using Maxent. An internal validation was adopted for model verification, and high AUC values were obtained (0.918 for RVF and 0.837-0.992 for vectors). By overlaying the RVF prediction map with the combined RVF vector prediction map using Fuzzy overlay tool ('AND' operator) of ArcMap 10.2, we got the first risk map of possible RVF vector transmission. This map was further overlaid with the latest livestock distribution map ('AND' operator) to generate the second risk map of possible RVF threat to domestic livestock. The south-west border provinces in China, Yunnan, Guangxi and Tibet were predicted to have a high possibility of RVF occurrence. Conditions conducive to the local amplification of RVF also exist in these areas. Temperature seasonality, mean temperature of dry season and precipitation of the driest month were considered as key environmental variables for RVF, and common environmental conditions were found conductive for vectors. It is suggested to establish proper surveillance systems in south-west border areas to minimize the possibility of RVF invasion. Our findings can serve as a valuable reference for prevention measures to be implemented.
裂谷热（RVF）是一种由蚊子传播的人畜共患病。自 1930 年首次爆发以来，裂谷热疫情在非洲造成了巨大的经济损失和公共卫生影响。2000 年，裂谷热传播到阿拉伯半岛，成为全球关注的疾病。在我们的研究中，通过生态位模型建立了基于地理信息系统的中国裂谷热发生风险评估。基于发生记录（粮农组织 EMPRES-i 的裂谷热记录、文献中的媒介记录和 GBIF）和高分辨率环境层，使用 Maxent 对中国裂谷热发生概率和五种潜在裂谷热媒介的分布预测图进行建模。采用内部验证对模型进行验证，得到了较高的 AUC 值（裂谷热为 0.918，媒介为 0.837-0.992）。通过在 ArcMap 10.2 中使用模糊叠加工具（“AND”运算符）将裂谷热预测图与综合裂谷热媒介预测图叠加，得到了第一个可能裂谷热媒介传播的风险图。进一步将该图与最新的牲畜分布图（“AND”运算符）叠加，生成了第二个国内牲畜面临裂谷热威胁的风险图。中国西南部边境省份云南、广西和西藏被预测为裂谷热发生的可能性较高。这些地区也存在有利于裂谷热局部放大的条件。温度季节性、旱季平均温度和最干旱月降水被认为是裂谷热的关键环境变量，而常见的环境条件被认为有利于媒介。建议在西南边境地区建立适当的监测系统，以最大程度地降低裂谷热入侵的可能性。我们的研究结果可以为实施预防措施提供有价值的参考。
