Seroprevalence of equine influenza in three southwestern states of Nigeria

Abstract

Equine influenza (EI) virus is one of the most economically significant pathogens causing respiratory disorders in equids. The recent outbreaks of EI in equids in North Western Nigeria showed EI virus is circulating in the Northern part of the country. This study determined the seroprevalence of EI infection in horses from the Southwestern states of Nigeria. One hundred sera samples from horses kept in three South Western states: Lagos, Ogun, and Oyo were screened for antibodies against influenza A nucleoprotein antigen using the direct ELISA method. Positive sera samples were thereafter examined thereafter further examined for haemagglutination inhibition (HI) antibodies to the H3 subtype of the influenza A virus. Antibodies were detected in 60 of the horses (22 Lagos, 8 Ogun and 30 Oyo). Although significantly higher seropositivity was observed in the male horses, seroprevalence of EI was also higher among 11- 15 years, exotic breeds and patrol horses. High seropositivity of horses in the South Western states of Nigeria to EIV infection is an indication that adequate monitoring of horse movement and continuous surveillance of the virus and vaccination should be strongly recommended.