Serological Evidence of Inter-Species Transmission of H9N2 Avian Influenza Virus in Poultry, Iran

Ducks and in-contact backyard chickens on 20 smallholder backyard farms in 4 districts of Shiraz, Southwest of Iran, were monitored for antibodies against H9N2 avian influenza virus using hemagglutinationinhibition (HI) test. A total of 200 unvaccinated ducks and backyard chickens were sampled. The mean H I titers and seroprevalence in ducks and backyard chickens were 8.3, 5.7 and 78.4, 62.9%, respectively. Results of this study revealed that the Scavenging ducks are the natural reservoir of avian influenza viruses and play an important role in the epidemiology of H9N2 avian influenza virus infection.