Susceptibility of a North American Culex quinquefasciatus to Japanese encephalitis virus

Authors: HUANG, YAN-JANG - Kansas State University; HARBIN, JULIE - Kansas State University; HETTENBACH, SUSAN - Kansas State University; Maki, Elin; Cohnstaedt, Lee; BARRETT, ALAN - University Of Texas Medical Branch; HIGGS, STEPHEN - Kansas State University; VANLANDINGHAM, DANA - Kansas State University

Submitted to: Vector-Borne and Zoonotic Diseases
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/1/2015
Publication Date: 11/1/2015
Citation: Huang, Y.S., Harbin, J.N., Hettenbach, S.M., Maki, E.C., Cohnstaedt, L.W., Barrett, A.D., Higgs, S., Vanlandingham, D.L. 2015. Susceptibility of a North American Culex quinquefasciatus to Japanese encephalitis virus. Vector-Borne and Zoonotic Diseases. 15(11):709-711.

Interpretive Summary: Japanese encephalitis virus (JEV) is a virus commonly found in the tropical and subtropical regions of Asia. This mosquito transmitted pathogen infects bird, pigs, and humans. Infections in birds may result in large distance dispersal of the virus, whereas pigs are a reservoir species. Infection in pigs maintains the virus locally and infects mosquitoes during feeding. Humans are an incidental host and do not develop high enough virus levels to infect mosquitoes, although infections do result in disease such as neural problems in humans and can be lethal. Human vaccination is an effective strategy for disease prevention and is used in several Asian countries. This research is important because JEV can invade North America at any time and will be a major threat to human and animal health. This study used field collected mosquitoes from Valdosta, Georgia to determine if North American mosquitoes were susceptible to JEV. The common house mosquito will become infected and able to transmit the virus after 14 days post infection.

Technical Abstract: Japanese encephalitis virus (JEV) is a flavivirus that is transmitted by Culex (Cx.) tritaeniorhynchus in tropical and subtropical regions of Asia. The endemic transmission cycle involves domestic pigs and avian species that serve as amplification hosts; humans are incidental hosts that cannot develop a high-titer viremia sufficient for mosquito infection. Although vaccination can be an effective strategy for disease prevention and is used extensively in multiple Asian countries, unvaccinated immunologically naive human populations can suffer from severe neurological sequelae. The potential introduction of JEV into North America would be a major threat to human and animal health. In this study, field-collected Cx. quinquefasciatus from Valdosta, Georgia, were tested for their susceptibility to JEV and their potential to develop a disseminated infection via per os infection. These results demonstrate that North American Cx. quinquefasciatus are susceptible to JEV infection and subsequent dissemination at 14 days post infection (d.p.i.). Detection of viral RNA in saliva from infected mosquitoes also indicates competent vectors for JEV can be found in North America.