Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, 66506, USA.
Biosecurity Research Institute, Kansas State University, Manhattan, KS, 66506, USA.
Parasit Vectors. 2018 Sep 20;11(1):519. doi: 10.1186/s13071-018-3103-2.
Cache Valley virus (CVV) is a mosquito-borne orthobunyavirus endemic in North America. The virus is an important agricultural pathogen leading to abortion and embryonic lethality in ruminant species, especially sheep. The importance of CVV in human public health has recently increased because of the report of severe neurotropic diseases. However, mosquito species responsible for transmission of the virus to humans remain to be determined. In this study, vector competence of three Culex species mosquitoes of public health importance, Culex pipiens, Cx. tarsalis and Cx. quinquefasciatus, was determined in order to identify potential bridge vector species responsible for the transmission of CVV from viremic vertebrate hosts to humans.
Variation of susceptibility to CVV was observed among selected Culex species mosquitoes tested in this study. Per os infection resulted in the establishment of infection and dissemination in Culex tarsalis, whereas Cx. pipiens and Cx. quinquefasciatus were highly refractory to CVV. Detection of viral RNA in saliva collected from infected Cx. tarsalis provided evidence supporting its role as a competent vector.
Our study provided further understanding of the transmission cycles of CVV and identifies Cx. tarsalis as a competent vector.
卡尤加谷病毒（CVV）是一种在北美流行的蚊虫传播正粘病毒。该病毒是一种重要的农业病原体，会导致反刍动物（尤其是绵羊）流产和胚胎致死。由于报告了严重的神经毒性疾病，CVV 对人类公共卫生的重要性最近有所增加。然而，仍需确定将病毒传播给人类的蚊虫种类。在这项研究中，为了确定可能传播 CVV 的桥梁媒介种类，从带毒脊椎动物宿主到人类，测定了三种具有公共卫生重要性的库蚊种类（库蚊、库蚊和田蚊）的媒介效能。
在本研究中测试的选定库蚊种类中观察到对 CVV 的敏感性存在差异。经口感染导致库蚊建立感染和传播，而库蚊和致倦库蚊对 CVV 高度抵抗。从感染的库蚊中采集的唾液中检测到病毒 RNA，为其作为有效媒介的作用提供了证据。
我们的研究进一步了解了 CVV 的传播周期，并确定库蚊和田蚊为有效媒介。
