"Take time to get a flu vaccine" tops the list of the Centers for Disease Control and Prevention's recommendations for protecting against flu. In healthy adults, the vaccine can reduce the risk of flu by 70 to 90 percent, says the CDC. While almost anyone over six months of age can receive a vaccination, the key word is "almost" because some contraindications exist.
Life-Threatening Allergic Reaction
People with a history of a life-threatening allergic reaction to a previous flu vaccine should not be vaccinated again, according to the FDA. People who have had less severe allergic responses to the vaccine should share this information with their healthcare provider prior to receiving a vaccination. The most dangerous type of life-threatening allergic reaction, anaphylaxis, usually follows a previous exposure to the allergen.
Hypersensitivity to Eggs
The viruses used to prepare the flu vaccine are grown in chicken eggs and trace amounts of eggs persist in the final vaccine. Although the amounts in question are small--less than a tenth of one percent, according to the FDA--these can be enough to trigger allergic reactions in some people. People with a history of hypersensitivity to eggs or any egg component should discuss this with their health care provider prior to receiving a vaccination. In some cases, a physician may recommend going ahead with the vaccine under conditions in a situation where emergency care is available if necessary.
Hypersensitivity to Antibiotics
According to the FDA, antibiotics are usually used to prevent contamination of the chicken eggs and improve the yield of flu vaccine lots. For the 2009 to 2010 flu season, the antibiotics used included neomycin, polymyxin and gentamicin. As with people allergic to eggs, only trace amounts persist in each dose. However, people with a hypersensitivity to these antibiotics should disclose this information to their health care provider. Two flu vaccines, Fluzone and Fluzone High-Dose, do not use any antibiotics during processing, although supplies may be limited.
References
- Centers for Disease Control and Prevention: CDC Says "Take 3" Actions To Fight The Flu
- Centers for Disease Control and Prevention: Seasonal Influenza Vaccine Safety: A Summary for Clinicians
- U.S. Food and Drug Administration: FDA: Approved Influenza Vaccines
- U.S. Food and Drug Administration: Fluzone and Fluzone High-Dose Prescribing Information
- CDC: Key Facts About Seasonal Flu Vaccine
