Surveillance for avian influenza viruses in wild birds at live bird markets, Egypt, 2014-2016.

ABSTRACT

AIM: Egypt is the habitat for a large number of bird species and serves as a vital stopover for millions of migratory birds during their annual migration between the Palearctic and Afrotropical ecozones. Surveillance for avian influenza viruses (AIVs) is critical to assessing risks for potential spreading of these viruses among domestic poultry. Surveillance for AIV among hunted and captured wild birds in Egypt was conducted in order to understand the characteristics of circulating viruses. METHODS: Sampling of wild bird species occurred in two locations along the Mediterranean Coast of Egypt in the period from 2014 to 2016. A total of 1316 samples (cloacal and oropharyngeal swabs) were collected from 20 different species of hunted or captured resident and migratory birds sold at live bird markets. Viruses were propagated then sequenced. Phylogenetic analysis and receptor binding affinities were studied. RESULTS: Eighteen AIVs (1.37%) were isolated from migratory Anseriformes at live bird markets. Further characterization of the viral isolates identified five hemagglutinin (H3, H5, H7, H9, and H10) and five neuraminidase (N1, N2, N3, N6, and N9) subtypes, which were related to isolates reported in the Eurasian region. Two of the 18 isolates were highly pathogenic H5N1 viruses related to clade 2.2.1, while three isolates were G1-like H9N2 viruses. CONCLUSIONS: Our data show significant diversity of AIVs in Anserifromes sold at live bird markets in Egypt. This allows for genetic exchanges between imported and enzootic viruses and put the exposed humans at a higher risk of infection.