Evaluating the mosquito vector range for two orthobunyaviruses: Oya virus and Ebinur Lake Virus

Abstract Background:Mosquito-borne viruses cause various infectious diseases in humans and animals. Oya virus (OYAV) and Ebinur lake virus (EBIV), belonging to the genus Orthobunyavirus within the Peribunyaviridae family, are recognized as neglected viruses with the potential to pose threats to animal or public health. The evaluation of vector competence is essential for predicting the arbovirus transmission risk. Methods: To investigate the range of mosquito vectors for OYAV and EBIV, four medically significant mosquitoes —Culex pipiens pallens, Culex quinquefasciatus, Aedes albopictus, and Aedes aegypti —were selected to measure their vector susceptibility through blood-feeding infection. The RNA copies and infection rates of various mosquito species were determined using RT-qPCR. Subsequently, susceptible mosquito species were examined to determine their vector competence. Results: The results revealed that Cx. pipiens pallens can support in vivo infection and multiplication of OYAV, while Cx. quinquefasciatus, Ae. albopictus,and Ae. aegypti exhibit lower susceptibility. Furthermore, Cx. pipiens pallenscan be infected by EBIV, posing a potential risk of virus transmission (with a transmission rate of up to 15.4%) at 7 days post-infection. In contrast, Cx. quinquefasciatus and Ae. albopictus exhibited poor vector competence. Conclusions: This study evaluated the possible transmission risk of OYAV and EBIV using four mosquito species. The findings indicate a potential risk of EBIV transmission in Cx. pipiens pallens.