Prevalence of influenza A/H3N2 virus in northern Iran from 2011 to 2013.

Background: Influenza A virus is the most virulent human pathogen and causes the most serious problem. Having epidemiological knowledge about this disease is important. The aim of this study was to determine the prevalence of influenza A/H3N2 virus infection in northern Iran from 2011 to 2013 using the real-time polymerase chain reaction (RT-PCR).