Molecular surveillance of avian influenza virus in domestic ducks: A provincial study



BACKGROUND: In the first time, avian Influenza (AI) infection, subtype H9N2, was isolated from chicken in 1988 in Qazvin province and since then has become endemic in Iran. Waterfowls, such as wild ducks, are natural reservoirs for all types of influenza A viruses and cause virus circulation in environment and poultry population. In 2006, Iranian Veterinary Organization confirmed that 135 dead swans in Gilan province were positive for H5N1 avian influenza virus. OBJECTIVES: The purpose of this study was to determine the role of domestic ducks in avian influenza virus circulation (subtypes: H5,H7 and H9) in Gilan province during 2010-2011 through molecular surveillance techniques. METHODES: 550 cloacal swabs from Mallard and Pekin ducks were tested in rural areas of Shaft and Fouman cities. Meanwhile a breeding farm in Gilan was tested by RT-PCR assay for detection of AI virus subtypes (H5,H7 and H9) according to OIE protocols. RESULTS: We did not detect AI viral RNA in 550 samples which were tested for type A and subtypes H5 and H7. CONCLUSIONS: While waterfowls could have a crucial role in emergence of new influenza virus strains, no AI viral RNA mentioned subtypes was detected for the mentioned subtypes. These findings could be due to restrict control programs following 2006 AI outbreak in the mentioned region. However, surveillance programs for monitoring AI viruses need to be continuously performed.