The FDA has approved the influenza vaccine formulation for the 2011-2012 influenza season.
The agency’s Vaccines and Related Biological Products Advisory Committee voted to determine the three strains they believe will be most likely to cause illness during the upcoming season based on virus samples and patterns collected from worldwide surveillance systems. These include:
- Influenza A/California/7/09 (H1N1)-like virus
- Influenza A/Perth/16/2009 (H3N2)-like virus
- Influenza B/Brisbane/60/2008-like virus
The strains selected for the 2011-2012 influenza season are identical to those contained in vaccines produced for the 2010-2011 season, but the agency emphasized annual immunization is vital for disease prevention.
“It is important to get vaccinated every year even if the strains in the vaccine do not change, because the protection received the previous year will diminish over time and may be too low to provide protection in the next year,” Karen Midthun, MD, director of the FDA’s Center for Biologics Evaluation and Research, said in a press release.
Currently, six U.S. companies are licensed to produce influenza vaccine in the following formulations: CSL Limited (Afluria); GlaxoSmith Kline Biologicals (Fluarix); ID Biomedical Corporation (FluLaval); MedImmune Vaccines Inc. (FluMist); Novartis Vaccines and Diagnostics Limited (Fluvirin);and Sanofi-Pasteur (Fluzone High-Dose and Fluzone Intradermal).
Sanofi-Pasteur’s intradermal influenza vaccine formulation – which is delivered into the skin rather than the muscle and requires a smaller needle – was newly approved in May 2011 and will be available for adults aged 18 through 64 years.
The agency warned that although the virus strains chosen are not always an optimal match for circulating strains, vaccination might still reduce the severity of illness or help prevent influenza-related complications.