A Young Boy with Asthma and Egg Allergy Gets a Flu Shot

FluBlok uses no egg but can't be given to persons younger than age 18 y.

It is early October and you are seeing a child in your office for his 5-year check up. While he is there, you write refills for an albuterol inhaler (he has mild intermittent asthma) and for an injectable epinephrine kit. At the age of 3 years he broke out in hives on his face and extremities after eating some scrambled eggs. He was subsequently seen by an allergist who confirmed the egg allergy with blood IgE testing.

Mom has read somewhere that children with asthma are at higher risk for complication from influenza and she requests that you vaccinate him today if it can be done safely.  He has never received a dose of flu vaccine before.

You tell mom that:

A. A new flu vaccine called FluBlok is egg-free and he should receive that.

B. It is acceptable to give him the flu shot, but he will need to be watched in the office for at least 30 minutes after being vaccinated.

C. If he didn't have a history of wheezing, you could give him the live attenuated flu vaccine (FluMist) since the amount of egg in that vaccine is almost undetectable.

D. He should not receive flu vaccine until it can be proven he has outgrown his egg allergy.

The mom is right, her son's asthma does put him into a higher risk group and he should be vaccinated yearly. At the same time, individuals with asthma who develop anaphylaxis are more likely to get into serious trouble. FluBlok is a new vaccine for this year. It will only be in the trivalent form and is made with a recombinant technology using no eggs in its manufacture so is very safe to use in egg-allergic individuals. Unfortunately, it is only labeled for use in persons aged 18 to 49 years. Pediatric studies are planned, so this may be an option for pediatricians in the future. 

This given, the answer is: B. It is acceptable to give him the flu shot, but he will need to be watched in the office for at least 30 minutes after being vaccinated.

Several expert groups including the Advisory Council on Immunization Practice (ACIP) recommend the use of a flu shot in this scenario with two caveats: First, the health care provider should be knowledgeable and prepared to treat an allergic reaction. Second, the vaccine recipient should be observed for at least 30 minutes for signs of an allergic reaction before being allowed to leave the health care facility. In my opinion, egg-allergic individuals should not receive their flu vaccine at a pharmacy.

The ACIP also states that  “...regardless of allergy history, all vaccines should be administered in settings in which personnel and equipment for rapid recognition and treatment of anaphylaxis are available.” Persons who can eat lightly cooked eggs (eg, scrambled eggs) are unlikely to be allergic, but the possibility of egg allergy is not precluded  by this. Someone who had more of a reaction than just urticaria following egg exposure (eg, angioedema, wheezing, recurrent vomiting, sense of impending doom) or who required emergency medical treatment should not receive any flu vaccine except FluBlok if appropriate per the package insert.

References:

CDC. Prevention and Control of Seasonal Influenza with Vaccines: Recommendations of the Advisory Committee on Immunization Practices (ACIP) - United States, 2014–15 Influenza Season. MMWR Morb Mortal Wkly Rep.2014;63:691-697. (August 15, 2014)