American Aedes japonicus japonicus, Culex pipiens pipiens, and Culex restuans mosquitoes have limited transmission capacity for a recent isolate of Usutu virus

Tyler A Bates; Christina Chuong; Pallavi Rai; Jeffrey Marano; Aaron Waldman; Amy Klinger; Joanna M Reinhold; Chloé Lahondère; James Weger-Lucarelli

doi:10.1016/j.virol.2020.12.023

American Aedes japonicus japonicus, Culex pipiens pipiens, and Culex restuans mosquitoes have limited transmission capacity for a recent isolate of Usutu virus

Virology. 2021 Mar:555:64-70. doi: 10.1016/j.virol.2020.12.023. Epub 2021 Jan 7.

Authors

Tyler A Bates¹, Christina Chuong¹, Pallavi Rai¹, Jeffrey Marano¹, Aaron Waldman¹, Amy Klinger¹, Joanna M Reinhold², Chloé Lahondère³, James Weger-Lucarelli⁴

Affiliations

¹ Department of Biomedical Sciences and Pathobiology, Virginia Tech, VA-MD Regional College of Veterinary Medicine, Blacksburg, VA, USA.
² Department of Biochemistry, Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061, USA.
³ Department of Biochemistry, Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061, USA; The Fralin Life Science Institute, Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061, USA; The Global Change Center, Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061, USA.
⁴ Department of Biomedical Sciences and Pathobiology, Virginia Tech, VA-MD Regional College of Veterinary Medicine, Blacksburg, VA, USA; The Fralin Life Science Institute, Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061, USA; The Global Change Center, Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061, USA. Electronic address: weger@vt.edu.

PMID: 33454558
DOI: 10.1016/j.virol.2020.12.023

Abstract

Usutu virus (USUV; Flavivirus) has caused massive die-offs in birds across Europe since the 1950s. Although rare, severe neurologic disease in humans has been reported. USUV is genetically related to West Nile virus (WNV) and shares an ecological niche, suggesting it could spread from Europe to the Americas. USUV's risk of transmission within the United States is currently unknown. To this end, we exposed field-caught Aedes japonicus, Culex pipiens pipiens, and Culex restuans-competent vectors for WNV-to a recent European isolate of USUV. While infection rates for each species varied from 7%-21%, no dissemination or transmission was observed. These results differed from a 2018 report by Cook and colleagues, who found high dissemination rates and evidence of transmission potential using a different USUV strain, U.S. mosquito populations, temperature, and extrinsic incubation period. Future studies should evaluate the impact of these experimental conditions on USUV transmission by North American mosquitoes.

Keywords: Aedes japonicus japonicus; Culex pipiens pipiens; Culex restuans; TM-Netherlands; United States; Usutu virus; Vector competence.

Publication types

Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Aedes / virology*
Animals
Birds / virology
Culex / virology*
Flavivirus / pathogenicity*
Flavivirus Infections* / transmission
Flavivirus Infections* / virology
Humans
Mosquito Vectors / virology*

Supplementary concepts

Usutu virus