Molecular epidemiology of circulating highly pathogenic avian influenza (H5N1) virus in chickens, in Bangladesh, 2007-2010

► Clade 2.2 viruses are firmly entrenched and endemic in Bangladesh. ► Several amino acid substitutions detected. ► These substitutions are not indicative of adaptation toward human infection. ► Correlation between genetic distances and temporal distances is significant. ► Evidence of long distance dispersal of the virus within the country.