WHO: Recommended composition of influenza virus vaccines for use in the 2012-2013 northern hemisphere influenza season
It is recommended that vaccines for use in the 2012-2013 influenza season (northern hemisphere winter) contain the following:
- an A/California/7/2009 (H1N1)pdm09-like virus;
- an A/Victoria/361/2011 (H3N2)-like virus;
- a B/Wisconsin/1/2010-like virus.