Florida Medical Entomology Laboratory, University of Florida IFAS, 200 9th Street SE, Vero Beach, FL.
Global Health Infectious Disease Research Program, University of South Florida, 3720 Spectrum Boulevard, Suite 304, Tampa, FL.
J Med Entomol. 2020 Sep 7;57(5):1627-1634. doi: 10.1093/jme/tjaa067.
The mosquito Culiseta melanura (Coquillett) is the primary enzootic vector of eastern equine encephalitis virus (EEEV), a zoonotic Alphavirus endemic to eastern North America. In its northern range, Cs. melanura is considered a strict avian biter, transmitting EEEV among susceptible birds in a cycle of enzootic amplification. In its southern range, however, Cs. melanura is more general in host use, feeding heavily upon birds but also reptiles and mammals. The goal of this study was to better understand how host use of Cs. melanura changes throughout the year in Florida, where year-round EEEV transmission is observed. Mosquitoes were sampled in 2018 from nine sites across three central Florida counties. In total, 213 Cs. melanura bloodmeals were identified by PCR consisting of 39 species of birds, reptiles, and mammals. Avian bloodmeals were prominent throughout the year (range = 30-85%), and songbirds were a large portion of identified bloodmeals (37.1%). Reptiles surpassed birds only in spring (April-June), and brown anole (Anolis sagrei Duméril and Bibron, 1837 [Reptilia: Dactyloidae]) was the most commonly detected single host species (22.1% overall). Mammalian bloodmeals were mainly observed in summer, with humans being the most fed on mammal (12.7% overall). This study reveals that in southern foci of EEEV transmission, Cs. melanura host use varies throughout the year with reptiles providing the majority of blood meals in spring (51.3%), and birds are fed on more than other host groups during all other seasons (50.6-70.1%). In addition, feeding on mammals increases during summer months, which may implicate Cs. melanura in epizootic transmission in Florida.
黑尾库蚊（Culiseta melanura）是东部马脑炎病毒（EEEV）的主要地方性媒介，EEEV 是一种在北美东部流行的嗜神经正粘病毒。在其北部地区，黑尾库蚊被认为是一种严格的禽类吸血者，在地方性放大循环中在易感鸟类中传播 EEEV。然而，在其南部地区，黑尾库蚊的宿主使用更加广泛，大量吸食鸟类，但也吸食爬行动物和哺乳动物。本研究的目的是更好地了解佛罗里达州黑尾库蚊全年的宿主使用情况，因为在佛罗里达州全年都有 EEEV 传播。2018 年，从佛罗里达州三个中心县的九个地点采集了蚊子。总共通过聚合酶链反应（PCR）鉴定了 213 只黑尾库蚊的血餐，包括 39 种鸟类、爬行动物和哺乳动物。全年都有明显的鸟类血餐（范围=30-85%），鸣禽是鉴定血餐的主要部分（37.1%）。爬行动物仅在春季（4 月至 6 月）超过鸟类，而棕色安乐蜥（Anolis sagrei Duméril and Bibron, 1837 [爬行动物：鬣蜥科]）是最常检测到的单一宿主物种（总体占 22.1%）。哺乳动物的血餐主要在夏季观察到，人类是最常被吸食的哺乳动物（总体占 12.7%）。本研究表明，在 EEEV 传播的南部焦点地区，黑尾库蚊的宿主使用全年都在变化，春季爬行动物提供的血餐最多（51.3%），而鸟类在其他季节（50.6-70.1%）被吸食的比例高于其他宿主群体。此外，夏季哺乳动物的吸血量增加，这可能使黑尾库蚊参与佛罗里达州的爆发性传播。
