Elias Susan P, Keenan Patrick, Kenney Joan L, Morris Sara R, Covino Kristen M, Robinson Sara, Foss Kimberly A, Rand Peter W, Lubelczyk Charles, Lacombe Eleanor H, Mutebi John-Paul, Evers David, Smith Robert P
1 Vector-Borne Disease Laboratory, Maine Medical Center Research Institute , Scarborough, Maine.
2 Biodiversity Research Institute , Portland, Maine.
Vector Borne Zoonotic Dis. 2017 May;17(5):325-330. doi: 10.1089/vbz.2016.2029. Epub 2017 Mar 13.
The intent of this study was to assess passerine eastern equine encephalitis virus (EEEv) seroprevalence during the breeding season in southern Maine by testing songbird species identified in the literature as amplifying hosts of this virus. In 2013 and 2014, we collected serum samples from songbirds at a mainland site and an offshore island migratory stopover site, and screened samples for EEEv antibodies using plaque reduction neutralization tests. We compared seasonal changes in EEEv antibody seroprevalence in young (hatched in year of capture) and adult birds at the mainland site, and also compared early season seroprevalence in mainland versus offshore adult birds. EEEv seroprevalence did not differ significantly between years at either site. During the early season (May), EEEv antibody seroprevalence was substantially lower (9.6%) in the island migrant adults than in mainland adults (42.9%), 2013-2014. On the mainland, EEEv antibody seroprevalence in young birds increased from 12.9% in midseason (June-August) to 45.6% in late season (September/October), 2013-2014. Seroprevalence in adult birds did not differ between seasons (48.8% vs. 53.3%). EEEv activity in Maine has increased in the past decade as measured by increased virus detection in mosquitoes and veterinary cases. High EEEv seroprevalence in young birds-as compared to that of young birds in other studies-corresponded with two consecutive active EEEv years in Maine. We suggest that young, locally hatched songbirds be sampled as a part of long-term EEEv surveillance, and provide a list of suggested species to sample, including EEEv "superspreaders."
本研究的目的是通过检测文献中确定为该病毒扩增宿主的鸣禽物种，评估缅因州南部繁殖季节的雀形目东部马脑炎病毒（EEEv）血清阳性率。2013年和2014年，我们在一个大陆地点和一个近海岛屿迁徙中途停留地点采集了鸣禽的血清样本，并使用蚀斑减少中和试验筛选样本中的EEEv抗体。我们比较了大陆地点幼鸟（捕获年份孵化）和成鸟中EEEv抗体血清阳性率的季节性变化，还比较了大陆成年鸟与近海成年鸟的早期血清阳性率。两个地点的EEEv血清阳性率在不同年份之间没有显著差异。在早期季节（5月），2013 - 2014年，岛屿迁徙成年鸟的EEEv抗体血清阳性率（9.6%）显著低于大陆成年鸟（42.9%）。在大陆，2013 - 2014年，幼鸟的EEEv抗体血清阳性率从中期季节（6 - 8月）的12.9%增加到后期季节（9月/10月）的45.6%。成年鸟的血清阳性率在不同季节之间没有差异（48.8%对53.3%）。根据蚊子中病毒检测增加和兽医病例增加来衡量，缅因州的EEEv活动在过去十年中有所增加。与其他研究中的幼鸟相比，缅因州幼鸟的高EEEv血清阳性率与连续两个活跃的EEEv年份相对应。我们建议将当地孵化的幼鸣禽作为长期EEEv监测的一部分进行采样，并提供一份建议采样物种的清单，包括EEEv“超级传播者”。
