Travel and age of influenza A (H1N1) 2009 virus infection

Abstract

Age distribution of 4,986 cases of influenza A (H1N1) 2009 in Japan was analyzed. Cases with a travel history within 10 days preceding the illness onset were significantly older than indigenous cases (p < 0.01) reflecting age-specific travel patterns. Border controls should account for the high frequency of infection among adults. © 2010 International Society of Travel Medicine.