A Serological survey of H5, H7 and H9 Subtypes of avian influenza viruses in domestic geeses and ducks of rural areas around Neor Lake in Ardabil province, Iran

Influenza viruses are an acute respiratory, highly contagious and zoonotic disease which belong to the Orthomyxoviridae family. H9 subtype in the group of low pathogenic avian influenza (LPAI) and H5 and H7 Subtypes in the group of high pathogenic avian influenza (HPAI), which cause mild to very severe disease with 100% mortality in birds. Considering that Neor Lake, located in the southeast of Ardabil, is the habitat of migratory waterfowl birds, and there is a possibility of contact these birds with native poultry in rural areas. Therefore, the present study was conducted to survey the serological prevalence of avian influenza viruse H5, H7 and H9 subtypes in domestic geeses and ducks of the rural areas around Neor Lake in Ardabil province, northwest of Iran. The cross-sectional study was conducted from August to November of 2016. In this survey, 115 blood samples were collected from rural domestic goose and duck. Serum samples were examined by HI test for differentiate H5, H7 and H9 subtypes of viruse and sera with titers ≥4 (log2) were considered positive. The results of this study showed that 17.95% of goose sera and 26.32% of duck sera were positive for H9N2 subtype of influenza virus. 5.26% of the duck sera were positive for H5N1 influenza virus. All tested sera were negative for H5N2, H7N1 and H7N7 avian influenza viruses. Regarding to relatively high sero-prevalence of H9N2 virus and as well as the low sero contamination of H5N1 virus in domestic rural ducks and geese, any direct or indirect contact of these birds with other poultry and human can spread the viruses. It is necessary to implement strict control programs such as continuous monitoring of circulating influenza viruses and vaccination in native ducks and geese of infected rural areas.