What flu viruses are included in the Northern Hemisphere seasonal vaccine for 2011-2012?

WHO recommended that the Northern Hemisphere's 2011–2012 seasonal influenza vaccine contain the following three vaccine viruses:

• 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 selected for the Northern Hemisphere for the 2010-2011 influenza vaccine.