The US Food and Drug Administration (FDA) announced that it has approved the influenza vaccine formulation for the 2011-2012 vaccine that will be used by the six manufacturers licensed to produce and distribute influenza vaccine for the United States.

Vaccination remains the cornerstone of preventing influenza, a contagious respiratory disease caused by influenza virus strains. The vaccine formulation protects against the three virus strains that surveillance indicates will be most common during the upcoming season and includes the same virus strains used for the 2010-2011 influenza season.

Between 5 per cent and 20 per cent of the US population develops influenza each year, leading to more than 200,000 hospitalizations from related complications, according to the US Centres for Disease Control and Prevention (CDC). Influenza-related deaths vary yearly, ranging from a low of about 3,000 to a high of 49,000 people.

“Vaccines to prevent seasonal influenza have a long and successful track record of safety and effectiveness in the United States,” said Karen Midthun, MD, director of FDA’s Centre for Biologics Evaluation and Research. “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 into the next year.”

In addition to the important role that health care providers play in recommending influenza vaccination for their patients, influenza vaccination of health care personnel is also important to protect themselves, their patients, their family, and the community from influenza. The FDA urges health care organizations to encourage their members to follow CDC’s Advisory Committee on Immunization Practices (ACIP) recommendations to get vaccinated.

The brand names and manufacturers of the vaccines for the upcoming season are: Afluria, CSL Limited; Fluarix, GlaxoSmithKline Biologicals; FluLaval, ID Biomedical Corporation; FluMist, MedImmune Vaccines Inc.; Fluvirin, Novartis Vaccines and Diagnostics Limited; and Fluzone, Fluzone High-Dose and Fluzone Intradermal, Sanofi Pasteur Inc. Fluzone Intradermal, approved on May 9, 2011, will be available for those ages 18 years through 64 years. This vaccine is delivered into the skin, rather than the muscle, using a very small needle.

Each year, experts from the FDA, World Health Organization, CDC, and others in the public health community study virus samples and patterns collected worldwide to identify virus strains likely to cause the most illness during the upcoming influenza season. Based on that information and the recommendations of the FDA’s Vaccines and Related Biological Products Advisory Committee, the strains selected for the 2011-2012 influenza season are: 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.

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, 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.

CDC’s ACIP recommends that everyone 6 months of age and older receive an annual influenza vaccination.

The FDA, an agency within the US Department of Health and Human Services, protects the public health by assuring the safety, effectiveness, and security of human and veterinary drugs, vaccines and other biological products for human use, and medical devices. The agency also is responsible for the safety and security of our nation’s food supply, cosmetics, dietary supplements, products that give off electronic radiation, and for regulating tobacco products.