Composition of the 2011-2012 Seasonal Influenza Vaccine
Both the trivalent inactivated influenza vaccine (TIV) and the live, attenuated influenza vaccine (LAIV) for the 2011-2012 season will include an A/California/7/2009 (H1N1)-like virus, an A/Perth/16/2009 (H3N2)-like virus, and a B/Brisbane/60/2008-like virus. These are the same viruses that were used for the 2010-2011 influenza vaccine. Global laboratory surveillance for influenza viruses is the basis for changing one or more of the vaccine strains each year.