The seasonal influenza vaccine is produced in chicken eggs. Ovalbumin, an egg protein, is often listed as a component of the purified vaccine on most drug-package inserts. The concentration of ovalbumin indicates the potential egg-allergen content of a vaccine.
Earlier ACIP guidelines recommended against giving the influenza vaccine to people with egg allergy, including those with a history of mild symptoms. However, several studies showed that influenza vaccine containing inactivated, or killed, virus is safe to give to people with egg allergy, especially those with a history of mild allergic reactions.
Influenza vaccines are now made with much lower ovalbumin concentrations than in the past; therefore, the level of potential egg protein allergens in a single dose of vaccine is extremely low.
The following are ACIP recommendations for the 2011 to 2012 influenza season:
Inactivated influenza vaccine (seasonal flu shot) is safe to give to people whose history of allergic reactions to egg has been limited to hives.
People with more severe allergic reactions to egg may receive the seasonal flu shot, but the vaccine must be given by a healthcare professional familiar with the signs and symptoms of an allergic reaction to egg and who has the ability to treat a severe reaction if one occurs.
