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On Monday, the U.S. Food and Drug Administration (FDA) said it had approved the formulation for the 2011-2012 vaccine . This year’s formulation is designed to protect against all three strains included in last years vaccine. Nevertheless, if you received a flu shot last year, you should still get vaccinated again this year: immunity to influenza viruses from vaccination declines over time and may be too low to provide protection after a year.
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. Currently, there are 136 national influenza centers in 106 countries that conduct year-round surveillance for influenza viruses and disease activity. Based on the information that’s been collected and the recommendations of the FDA’s Vaccines and Related Biological Products Advisory Committee, the strains selected for the Northern Hemisphere’s 2011-2012 influenza season are:
- A/California/7/2009 (H1N1)-like virus (pandemic (H1N1) 2009 influenza virus)
- A/Perth /16/2009 (H3N2)-like virus
- B/Brisbane/60/2008-like virus
Six manufacturers are licensed to produce and distribute flu vaccines in the U.S. this year (brand names in parenthesis): CSL Limited (Afluria); GlaxoSmithKline Biologicals (Fluarix); ID Biomedical Corporation (FluLaval); MedImmune Vaccines Inc. (FluMist); Novartis Vaccines and Diagnostics Limited (Fluvirin); and Sanofi Pasteur Inc. (Fluzone, Fluzone High-Dose and Fluzone Intradermal).
For 2011, a new vaccine is also available. Sanofi’s Fluzone Intradermal was approved by the FDA in May . It’s a shot that, unlike traditional flu shots, is injected under the skin instead of into the muscle. The company says the needle is 90% shorter than the kind used for intramuscular injection.
Cold and flu germs hide everywhere and everyone is at risk. Early last year, the CDC’s Advisory Committee on Influenza Practices recommended that everyone 6 months of age and older receive an annual influenza vaccination .
Flu season runs from November to April — most cases occur between late December and early March. Every winter, approximately 10-20% of people get the flu . In children, the odds are even worse, with up to 40% of children becoming clinically ill due to the influenza virus. The most effective method to prevent infection, reduce symptom severity if you do get sick, and prevent the spread of virus to others is annual vaccination. Besides vaccination, one of the easiest ways to avoid getting sick is to wash your hands.
- FDA approves vaccines for the 2011-2012 influenza season. U.S. Food and Drug Administration News Release. 2011 Jul 18.
- FDA Licenses Sanofi Pasteur’s New Influenza Vaccine Delivered by Intradermal Microinjection. Sanofi Pasteur. 201 May 10.
- CDC’s Advisory Committee on Immunization Practices (ACIP) Recommends Universal Annual Influenza Vaccination. Centers for Disease Control and Prevention press release. 2010 Feb 24.
- Evans M. Flu shot. Can Fam Physician. 2005 Nov;51:1511-2, 1515-6.