Influenza-A Circulation in Vietnam through Data Analysis of Hemagglutinin Entires

Hemagglutinin is a glycoprotein locating on surface of influenza virus. Influenza A human hemagglutinin protein H1, H2, H3, H5, H7, H9 sequences on NCBI database from Vietnam were retrieved and analyzed to find out the pattern of viral circulation within the country in the last 12 years. 1060 sequences were collected and analyzed. The results revealed five main influenza A virus including H5N1, H3N2, H1N1, H6N2, and H9N2 circulating in Vietnam with high level of genetic compatibility, identified as reassortants between a wide variety viral genotypes and share common mechanisms of spread. The most two popular host are human and poultry. The two recent pandemics avian H5N1 in 2005 and Swine H1N1 in 2009 did show significant effects on the viral circulation in Vietnam. H5N1 and H1N1 subtype remain pathogenic and require close surveillance.