Division of Epidemiology of Microbial Diseases, Yale School of Public Health, 60 College Street, New Haven, CT 06520-8034, USA.
Am J Trop Med Hyg. 2010 Feb;82(2):337-43. doi: 10.4269/ajtmh.2010.09-0506.
West Nile virus (WNV) perpetuates in an enzootic transmission cycle involving Culex mosquitoes and virus-competent avian hosts. In the northeastern United States, the enzootic vectors, Cx. pipiens and Cx. restuans, feed preferentially on American robins (Turdus migratorius), suggesting a key role for this bird species in the WNV transmission cycle. We examined the role of American robin communal roosts as virus amplification foci in greater New Haven, Connecticut. Robin communal roosts were located by radio tracking. After mid-August, when most robins were using the roosts, Cx. pipiens and Cx. restuans fed often on robins and were significantly more infected with WNV at communal roosts than at non-roosting sites. We also identified 6.4% human-derived blood meals in Aedes vexans in communal roosts. Our results indicate that communal roosts act as late-season amplification foci facilitating transmission to humans because of high infection rates, high abundance, and feeding patterns of enzootic and bridge vectors.
西尼罗河病毒（WNV）在涉及库蚊属蚊子和具有病毒感染能力的禽类宿主的地方性传播循环中持续存在。在美国东北部，地方性传播媒介库蚊属和致倦库蚊属优先以美洲知更鸟（Turdus migratorius）为食，这表明这种鸟类在 WNV 传播循环中发挥了关键作用。我们研究了在康涅狄格州纽黑文地区，美洲知更鸟的公共栖息地作为病毒扩增焦点的作用。通过无线电追踪来定位知更鸟的公共栖息地。8 月中旬以后，当大多数知更鸟开始使用栖息地时，库蚊属和致倦库蚊属经常以知更鸟为食，并且在公共栖息地的感染率显著高于非栖息地。我们还在公共栖息地的 Aedes vexans 中发现了 6.4%的人血。我们的研究结果表明，公共栖息地作为晚期的扩增焦点，由于高感染率、丰富度和地方性及桥梁媒介的取食模式，促进了向人类的传播。
