PNAS:北美鸟类与西尼罗河病毒

美国加州大学洛杉矶分校科研人员报告了西尼罗河病毒对各种北美鸟类物种的存活率的影响。自从西尼罗河病毒于1999年引入到北美以来，人们已经把它与数以百万计的原产鸟类的死亡联系在了一起。然而，这种病毒对于各物种的影响尚未得到充分的记录。Ryan Harrigan及其同事使用1992年到2007年间美国各地500多个鸟类环志站的标记-再捕获数据，研究了西尼罗河病毒对49个鸟类物种的影响。这组作者在49种鸟的23种之中，即被研究的物种的47%之中发现了与西尼罗河病毒有关的存活率下降。对于这23个物种中的11种，存活率在该病毒最初到来之后下降，但是后来恢复到了病毒到来之前的估计数字。对于剩下的12个物种，存活率下降并在之后的年份保持在病毒到来之前的估计数字之下。新大陆麻雀、地雀和莺雀群体都拥有大得不成比例的受该病毒影响的物种，这提示种系发生可能影响物种对该病毒的易感性。这些结果提示，传染病的引入可能对原产种群有大而长期的影响。

原文链接：

Persistent impacts of West Nile virus on North American bird populations

原文摘要：

Since its introduction to North America in 1999, West Nile virus (WNV) has had devastating impacts on native host populations, but to date these impacts have been difficult to measure. Using a continental-scale dataset comprised of a quarter-million birds captured over nearly two decades and a recently developed model of WNV risk, we estimated the impact of this emergent disease on the survival of avian populations. We find that populations were negatively affected by WNV in 23 of the 49 species studied (47%). We distinguished two groups of species: those for which WNV negatively impacted survival only during initial spread of the disease (n = 11), and those that show no signs of recovery since disease introduction (n = 12). Results provide a novel example of the taxonomic breadth and persistent impacts of this wildlife disease on a continental scale. Phylogenetic analyses further identify groups (New World sparrows, finches, and vireos) disproportionally affected by temporary or persistent WNV effects, suggesting an evolutionary dimension of disease risk. Identifying the factors affecting the persistence of a disease across host species is critical to mitigating its effects, particularly in a world marked by rapid anthropogenic change.

doi: 10.1073/PNAS.1507747112

作者：T. Luke George