Viral genetic sequence variations in pandemic H1N1/2009 and seasonal H3N2 influenza viruses within an individual, a household and a community.

Background: There are few data in the literature on viral sequence variation between host generations/successive transmission events. Relatively little is known about the sequence heterogeneity of the influenza viruses transmitted within families.

Objectives: To study the molecular epidemiology of influenza virus and to determine the sequence variation within an individual, a household and a community during the first wave of influenza pandemic in 2009.