Effect of Temperature on Replication of Epizootic Hemorrhagic Disease Viruses in Culicoides sonorensis (Diptera: Ceratopogonidae)

作者：Mark G. Ruder, David E. Stallknecht, Elizabeth W. Howerth, Deborah L. Carter, R. S. Pfannenstiel, Andrew B. Allison, Daniel G. Mead · 发表于：Journal of Medical Entomology · 年份：2015 · DOI：10.1093/jme/tjv062 · 被引用次数：29 · 研究领域：Vector-Borne Animal Diseases、Viral Infections and Vectors、Animal Disease Management and Epidemiology

Replication of arboviruses, including orbiviruses, within the vector has been shown to be temperature dependent. Cooler ambient temperatures slow virus replication in arthropod vectors, whereas viruses replicate faster and to higher titers at warmer ambient temperatures. Previous research with epizootic hemorrhagic disease virus (EHDV) serotype 1 demonstrated that higher temperatures were associated with shorter extrinsic incubation periods in Culicoides sonorensis Wirth & Jones, a confirmed vector of EHDV in North America. To further our understanding of the effect of temperature on replication of EHDV within the vector, C. sonorensis were experimentally infected with one of three EHDV strains representing three serotypes (1, 2, and 7). Midges were fed defibrinated white-tailed deer (Odocoileus virginianus) blood spiked with EHDV (≥10(6.5) TCID(50)/ml) through a parafilm membrane using an artificial feeding device and were then held at 20, 25, or 30°C. In addition to this in vitro method, a white-tailed deer experimentally infected with EHDV-7 was used to provide an infectious bloodmeal to determine if the results were comparable with those from the in vitro feeding method. Whole midges were processed for virus isolation and titration at regular intervals following feeding; midges with ≥10(2.7) TCID(50) were considered potentially competent to transmit virus. The virus recovery rates were high throughout the study and all three viruses replicated within C. sonorensis to high...