Composition of the 2012-2013 Seasonal Influenza Vaccine
Both the trivalent inactivated influenza vaccine (TIV) and the live, attenuated influenza vaccine (LAIV) for the 2012-2013 season will include an A/California/7/2009 (H1N1)-like virus, an A/Victoria/361/2011 (H3N2)-like virus, and a B/Wisconsin/1/2010-like virus (B/Yamagata lineage). Global laboratory surveillance for influenza viruses is the basis for changing one or more of the vaccine strains each year.