Vector-Host Interactions of Culiseta melanura in a Focus of Eastern Equine Encephalitis Virus Activity in Southeastern Virginia.
Vector-Host Interactions of Culiseta melanura in a Focus of Eastern Equine Encephalitis Virus Activity in Southeastern Virginia.
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DOI：
10.1371/journal.pone.0136743
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发表时间：
2015
期刊：
影响因子：
3.7
通讯作者：
Andreadis TG
中科院分区：
文献类型：
--
作者：
Molaei G;Armstrong PM;Abadam CF;Akaratovic KI;Kiser JP;Andreadis TG
东部马脑炎病毒（EEEV）引起一种高致病性蚊媒人畜共患病，导致美国东部人和马的严重疾病零星暴发。Culiseta（Cs.）在大多数地理区域中，黑尾目是EEEV的主要媒介，但在大西洋中部区域，其对特定鸟类和哺乳动物宿主的摄食模式在很大程度上是未知的。本研究的目的是：1）确定鸟类宿主的Cs。2）评估在强病毒传播季节中病毒活动的空间和时间模式; 3）研究Cs的潜在作用。在EEEV向人类和马的流行性/动物流行性传播中，因此，我们于2013年在弗吉尼亚州萨福克郡的55个地点收集了蚊子，并通过线粒体细胞色素B基因的核苷酸测序PCR产物鉴定了饱食蚊子的血餐来源。我们还检查了现场收集的蚊子感染EEEV的证据，使用载体测试，细胞培养和PCR。分析188个充血的Cs。2013年4月至10月期间采集的黑尾两栖类样本表明，95.2%、4.3%和0.5%的黑尾两栖类分别从鸟类、哺乳动物和爬行动物宿主获得血粉。美洲知更鸟是最常见的Cs宿主。黑尾椋鸟（占血粉的42.6%），其次是北方红雀（16.0%）、欧洲椋鸟（11.2%）、卡罗莱纳鹪鹩（4.3%）和普通八哥（4.3%）。在106个蚊池中检测到EEEV。病毒阳性池的数量在7月下旬达到峰值，有22个阳性池，最大似然估计（MLE）感染率为每1，000只蚊子4.46。我们的研究结果强调了Cs的重要性。黑尾燕是一种区域性EEEV载体，其基于频繁取食病毒感受态鸟类物种。从哺乳动物宿主获得的一小部分血粉表明，该物种可能偶尔会导致EEEV的流行/动物流行性传播。
Eastern equine encephalitis virus (EEEV) causes a highly pathogenic mosquito-borne zoonosis that is responsible for sporadic outbreaks of severe illness in humans and equines in the eastern USA. Culiseta (Cs.) melanura is the primary vector of EEEV in most geographic regions but its feeding patterns on specific avian and mammalian hosts are largely unknown in the mid-Atlantic region. The objectives of our study were to: 1) identify avian hosts of Cs. melanura and evaluate their potential role in enzootic amplification of EEEV, 2) assess spatial and temporal patterns of virus activity during a season of intense virus transmission, and 3) investigate the potential role of Cs. melanura in epidemic/epizootic transmission of EEEV to humans and equines. Accordingly, we collected mosquitoes at 55 sites in Suffolk, Virginia in 2013, and identified the source of blood meals in engorged mosquitoes by nucleotide sequencing PCR products of the mitochondrial cytochrome b gene. We also examined field-collected mosquitoes for evidence of infection with EEEV using Vector Test, cell culture, and PCR. Analysis of 188 engorged Cs. melanura sampled from April through October 2013 indicated that 95.2%, 4.3%, and 0.5% obtained blood meals from avian, mammalian, and reptilian hosts, respectively. American Robin was the most frequently identified host for Cs. melanura (42.6% of blood meals) followed by Northern Cardinal (16.0%), European Starling (11.2%), Carolina Wren (4.3%), and Common Grackle (4.3%). EEEV was detected in 106 mosquito pools of Cs. melanura, and the number of virus positive pools peaked in late July with 22 positive pools and a Maximum Likelihood Estimation (MLE) infection rate of 4.46 per 1,000 mosquitoes. Our findings highlight the importance of Cs. melanura as a regional EEEV vector based on frequent feeding on virus-competent bird species. A small proportion of blood meals acquired from mammalian hosts suggests the possibility that this species may occasionally contribute to epidemic/epizootic transmission of EEEV.