The U.S. Food and Drug Administration announced today (Mon. Aug. 2) that it has approved vaccines for the 2010-2011 influenza season in the United States.
The new seasonal influenza vaccine protects against three strains of influenza, including the 2009 pandemic H1N1 influenza virus.
Vaccines for the 2010-2011 seasonal influenza contain the following strains:
• A/California/7/09 (H1N1)-like virus (pandemic (H1N1) 2009 influenza virus)
• A/Perth /16/2009 (H3N2)-like virus
• B/Brisbane/60/2008-like virus
Last flu season, two separate vaccines were needed to protect against seasonal flu and the 2009 H1N1 pandemic flu virus, because H1N1 emerged after production was underway on the seasonal vaccine.
There is always a possibility of a less than optimal match between the virus strains predicted to circulate and the virus strains that end up causing the most illness. However, the FDA says even if the vaccine and the circulating strains are not an exact match, the vaccine may reduce the severity of the illness or may help prevent influenza-related complications.
Strains are selected for the seasonal vaccine by the FDA, World Health Organization, CDC, and other institutions, who study virus samples and patterns collected worldwide to identify strains likely to cause the most illness during the upcoming season.