Center for Grain and Animal Health Research, Agricultural Research Service, United States Department of Agriculture, Manhattan, KS 66502, USA.
Florida Medical Entomology Laboratory, Institute of Food and Agricultural Sciences, University of Florida, Vero Beach, FL 32962, USA.
Viruses. 2021 Mar 5;13(3):410. doi: 10.3390/v13030410.
Epizootic hemorrhagic disease virus (EHDV; family , genus ) is an arthropod-borne virus of ungulates, primarily white-tailed deer in North America. , the only confirmed North American vector of EHDV, is rarely collected from Florida despite annual virus outbreaks. is an abundant species in Florida and is also a confirmed vector of the closely related Bluetongue virus. In this study, oral challenge of was performed to determine vector competence for EHDV serotype-2. Field-collected female midges were provided bovine blood spiked with three different titers of EHDV-2 (5.05, 4.00, or 2.94 logPFUe/mL). After an incubation period of 10 days or after death, bodies and legs were collected. Saliva was collected daily from all females from 3 days post feeding until their death using honey card assays. All samples were tested for EHDV RNA using RT-qPCR. Our results suggest that is a weakly competent vector of EHDV-2 that can support a transmissible infection when it ingests a high virus titer (29% of midges had virus positive saliva when infected at 5.05 logPFUe/mL), but not lower virus titers. Nevertheless, due to the high density of this species, particularly in peninsular Florida, it is likely that plays a role in the transmission of EHDV-2.
流行性出血热病毒（EHDV；科，属）是一种节肢动物传播的病毒，主要感染北美的白尾鹿。 ，是 EHDV 的唯一确认的北美媒介，但尽管每年都会爆发病毒，但在佛罗里达州却很少采集到。 在佛罗里达州非常丰富，也是密切相关的蓝舌病病毒的确认媒介。在这项研究中，通过口服挑战 ，以确定其对 EHDV 血清型 2 的媒介能力。采集野外采集的雌性蚋，并用三种不同滴度的 EHDV-2（5.05、4.00 或 2.94 logPFUe/mL）感染牛血。经过 10 天的潜伏期或死亡后，收集身体和腿。从所有感染后 3 天开始到死亡为止，每天使用蜂蜜卡检测法从所有雌性个体中收集唾液。使用 RT-qPCR 检测所有样本中的 EHDV RNA。我们的结果表明， 是 EHDV-2 的弱媒介，可以在摄入高病毒滴度（当感染 5.05 logPFUe/mL 时，有 29%的蚋唾液中含有病毒）时支持可传播的感染，但不能支持较低的病毒滴度。尽管如此，由于该物种密度很高，尤其是在佛罗里达州半岛，它很可能在 EHDV-2 的传播中发挥作用。
