Center for Tropical Research, Institute of the Environment and Sustainability, University of California, 619 Charles E. Young Drive East, Los Angeles, California, 90095, USA.
Glob Chang Biol. 2014 Aug;20(8):2417-25. doi: 10.1111/gcb.12534. Epub 2014 Feb 27.
Since first introduced to North America in 1999, West Nile virus (WNV) has spread rapidly across the continent, threatening wildlife populations and posing serious health risks to humans. While WNV incidence has been linked to environmental factors, particularly temperature and rainfall, little is known about how future climate change may affect the spread of the disease. Using available data on WNV infections in vectors and hosts collected from 2003-2011 and using a suite of 10 species distribution models, weighted according to their predictive performance, we modeled the incidence of WNV under current climate conditions at a continental scale. Models were found to accurately predict spatial patterns of WNV that were then used to examine how future climate may affect the spread of the disease. Predictions were accurate for cases of human WNV infection in the following year (2012), with areas reporting infections having significantly higher probability of presence as predicted by our models. Projected geographic distributions of WNV in North America under future climate for 2050 and 2080 show an expansion of suitable climate for the disease, driven by warmer temperatures and lower annual precipitation that will result in the exposure of new and naïve host populations to the virus with potentially serious consequences. Our risk assessment identifies current and future hotspots of West Nile virus where mitigation efforts should be focused and presents an important new approach for monitoring vector-borne disease under climate change.
自 1999 年首次引入北美以来，西尼罗河病毒（WNV）迅速在整个大陆传播，威胁到野生动物种群，并对人类健康构成严重威胁。虽然 WNV 的发病率与环境因素有关，特别是温度和降雨量，但对于未来气候变化如何影响疾病的传播知之甚少。利用 2003-2011 年收集的媒介和宿主中 WNV 感染的可用数据，并使用根据其预测性能加权的 10 种物种分布模型套件，我们在大陆范围内模拟了当前气候条件下 WNV 的发病率。模型被发现能够准确预测 WNV 的空间分布，然后利用这些模型来研究未来气候如何影响疾病的传播。对 2012 年人类 WNV 感染病例的预测是准确的，报告感染的地区与我们模型预测的存在概率显著更高。在未来气候下，北美 2050 年和 2080 年的 WNV 预计地理分布显示出疾病适宜气候的扩大，这是由更高的温度和更低的年降雨量驱动的，这将导致新的和天真的宿主群体接触到病毒，可能会产生严重后果。我们的风险评估确定了当前和未来的西尼罗河病毒热点地区，应集中精力进行缓解，并为气候变化下的虫媒疾病监测提供了一种重要的新方法。
