Viruses associated with respiratory disease of horses in New Zealand: an update

Abstract

Viruses causing or associated with respiratory disease in horses worldwide are reviewed. Results are presented from a serological survey of 121 New Zealand foals and horses that had been affected by respiratory disease, determining the prevalence of antibodies in this country to the major viruses associated with similar disease overseas. To date there is no evidence of equine influenza virus in New Zealand. Both equine herpesvirus type 1 and 2 have been frequently isolated and show high serological prevalences. Serological evidence of equine rhinovirus type 1 and type 2 is presented with a prevalence of 12.3% and 41.2% respectively observed in foal sera, and 37.7% and 84.9% in adult horse sera. Antibody reacting to equine viral arteritis virus antigen was detected in 3/121 test sera. Equine adenovirus has been isolated on occasions and has shown a 39% serological prevalence in one study reviewed. Progress in New Zealand equine virus research is discussed.