"My three year old had a skin breakout we think was due to eggs - is it safe to do a flu shot?" It's a question being asked to every doctor who takes care of kids during flu season. "On the one hand we are concerned about the devastating effects of the new strain of flu, and on the other we aren't sure if a history of eggs sensitivity is enough to hold the shot or spray," said Bobby Q. Lanier, M.D., clinical professor of pediatrics at the University of North Texas HSC in Fort Worth, Texas, and executive medical director of the American College of Allergy, Asthma and Immunology (ACAAI).
The process of using fertilized chicken eggs to grow the virus associated with influenza was a medical breakthrough in 1931, Dr. Lanier said. Before that discovery, the only treatment for flu was to transfuse blood from a survivor of flu to one with the symptoms. The egg technology opened up vaccines to literally billions of people.
While the vaccine production now removes virtually every trace of chicken protein, there were historical issues of vaccines causing major allergic reaction because of retained egg protein. Amal Assa'ad, M.D., professor at Cincinnati Children's Hospital Medical Center in Cincinnati, Ohio, and vice chair of the ACAAI Adverse Reactions Foods Committee, will be presenting a novel way to classify children (and adults) as to their risks at the ACAAI Annual Meeting in Miami Beach, Fla.
"Some allergic patients are at greater risk of a reaction to the 2009 vaccines, both H1N1 and the usual respiratory viruses in the normal flu shot and mist. This high risk group includes patients with a history of a positive skin test or an elevated blood test to egg, who have had allergic reactions to eating egg, or who had a reaction to flu vaccination in the past," Dr. Assa'ad said.
Dr. Ass'ad has classified possible reactors in five color-coded groups and makes these suggestions:
•Blue Group - Minimal Risk. Patients with a history of skin test or serum IgE positivity or clinical reaction to either egg or previous flu vaccines - who can eat whole eggs safely without allergic reaction - should receive either the inactivated (IM) or live (intranasal) vaccine at their general pediatrician's office. This should comprise the vast majority of patients this year.
•Green Group - Low Risk. Children who have had recent (less than 2 years) skin test or serum IgE positivity to egg, but who do not react to ingestion of baked products containing egg, should receive the inactivated flu vaccine at full-strength (or graded challenge in special cases) at their general pediatrician's office or the allergy clinic. Adrenalin should be available.
•Yellow Group - Moderate Risk. Any patient avoiding eggs entirely for any medical reason should be evaluated by an allergist. Patients who have had recent skin test or serum IgE positivity to egg who do react to baked products containing egg, or who have a history of allergic reaction to inactivated flu vaccine, should also be evaluated by an allergist. In order to provide the vaccine safely to these patients, we recommend skin testing with the full-strength inactivated flu vaccine and egg extract prior to vaccine administration. If the skin tests are negative, we recommend that the rest of the vaccine be given at full-strength or as a graded challenge. If the vaccine skin test is positive, we would either desensitize the patient to the vaccine and administer it or give chemoprophylaxis in special cases with a flu medication daily for the entire flu season.