Pediatric hospitalizations due to influenza in 2010 in Argentina.

To the Editor: Much concern has been raised about the upcoming 2010–2011 flu season in the Northern Hemisphere. In preparation for this event, we investigated the burden of influenza during the 2010 season in the Southern Hemisphere in the same hospitals involved in our report in the Journal (Jan. 7 issue)1 of serious disease in children in Argentina during the 2009 season. During 2009, Argentina had the third largest number of deaths due to pandemic influenza in the Americas.2 As reported in the Journal, 1 our retrospective case series consisted of 251 hospitalizations and 13 deaths between May 1 and July . . .