AUTHOR=Cai Tong , Liu Ran , Jiang Yuting , Jia Nan , Jian Xianyi , Cheng Xiaolan , Song Fenglin , Guo Xiaoxia , Zhao Tongyan 

TITLE=Vector competence evaluation of mosquitoes for Tahyna virus PJ01 strain, a new Orthobunyavirus in China

JOURNAL=Frontiers in Microbiology

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2023.1159835

DOI=10.3389/fmicb.2023.1159835

ISSN=1664-302X

ABSTRACT=<sec><title>Introduction</title><p>Tahyna virus (TAHV), an arbovirus of the genus <italic>Orthobunyavirus</italic>, is a cause of human diseases and less studied worldwide. In this study, a new strain of TAHV was isolated from <italic>Aedes</italic> sp. mosquitoes collected in Panjin city, Liaoning province. However, the competent vector of TAHV in China is still unknown.</p></sec><sec><title>Methods</title><p>The genome of newly isolated TAHV was sequenced and phylogenetic analysis is performed. <italic>Aedes albopictus</italic> and <italic>Culex pipiens pallens</italic> were orally infected with artificial virus blood meals (1:1 of virus suspension and mouse blood), the virus was detected in the midgut, ovary, salivary gland and saliva of the mosquitoes. Then, the transmission and dissemination rates, vertical transmission and horizontal transmission of the virus by the mosquitoes were assessed.</p></sec><sec><title>Results</title><p>Phylogenetic analysis revealed that the virus shared high similarity with TAHV and was named the TAHV PJ01 strain. After oral infection with virus blood meals, <italic>Ae. albopictus</italic> showed positive for the virus in all tested tissues with an extrinsic incubation period of 2 days and a fluctuating increasement of transmission and dissemination rates. Whereas no virus was detected in the saliva of <italic>Cx. pipiens pallens</italic>. Suckling mice bitten by infectious <italic>Ae. albopictus</italic> developed obvious neurological symptoms, including inactivity, hind-leg paralysis and difficulty turning over, when the virus titer reached 1.70×10<sup>5</sup> PFU/mL in the brain. Moreover, TAHV was detected in the eggs, larvae and adults of F1 offspring of <italic>Ae. albopictus</italic>.</p></sec><sec><title>Discussion</title><p><italic>Ae. albopictus</italic> is an efficient vector to transmit TAHV but <italic>Cx. pipiens pallens</italic> is not. <italic>Ae. albopictus</italic> is also a reservoir host that transmits the virus vertically, which further increases the risk of outbreaks. This study has important epidemiological implications for the surveillance of pathogenic viruses in China and guiding comprehensive vector control strategies to counteract potential outbreaks in future.</p></sec>