Infectivity of equine H3N8 influenza virus in bovine cells  and calves.
BACKGROUND
Serological evidence for influenza A, subtype H1 and H3 virus infections of bovines, associated with respiratory disease and decreased milk production, has been reported. Equine H3N8 influenza virus circulates widely and was responsible for the introduction of H3N8 influenza into canines.


OBJECTIVE
To explore the possibility that equine H3N8 influenza might also infect bovines.


METHODS
To assess the incidence of seroconversion in the field, a retrospective survey of bovine serum samples was carried out. Also, primary cultures of bovine nasal turbinate cells, and live beef calves, were studied for their permissiveness to infection.


CONCLUSIONS
We found serological evidence of exposure of bovines in Kentucky to H3 influenza. We demonstrate that cultured bovine respiratory epithelium is permissive for the growth of equine H3N8 influenza virus in vitro, but this virus does not replicate extensively or produce disease in experimentally inoculated cattle.
Department of Veterinary Science, University of Kentucky, Lexington, KY 40546-0099, USA.
Chengbin
C
Lin
Robert E
RE
Holland
Morgan H
MH
McCoy
Jennifer
J
Donofrio-Newman
Mary L
ML
Vickers
Thomas M
TM
Chambers
D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology* / Q000473:pathology / Q000821:virology*; D002478:Cells, Cultured; D004195:Disease Models, Animal; D004847:Epithelial Cells / Q000821:virology; D006734:Horse Diseases / Q000821:virology; D006736:Horses; D053123:Influenza A Virus, H3N8 Subtype / Q000254:growth & development / Q000302:isolation & purification / Q000472:pathogenicity*; D007629:Kentucky / Q000453:epidemiology; D009976:Orthomyxoviridae Infections / Q000453:epidemiology / Q000473:pathology / Q000662:veterinary* / Q000821:virology; D012189:Retrospective Studies; D016036:Seroepidemiologic Studies