Egg allergy and the 2013 Influenza vaccine

Let’s start with a patient case.  A 55 year old female patient is seen in clinic that has recently been diagnosed with COPD.  After suffering from influenza last year, she is now seeking the influenza vaccine.  Upon further questioning, the patient confirms she is allergic to eggs.  When she eats eggs, she develops hives but no other symptoms.  What can we tell her?

Egg allergies are one of the most common food allergies in children with rates reported in up to 2% of children¹. While rates in adults are estimated to be much lower, this issue may soon be relevant considering the upcoming influenza season.  In past years, most prescribing information for the various influenza vaccines has listed allergy to eggs as a ‘Contraindication’ for use as the vaccines are prepared from influenza virus propagated in embryonated chicken eggs.  The necessity of avoiding the vaccines in patients with only minor reactions has decreased in recent years and much of the prescribing information has been revised to only list severe reactions (ie. anaphylaxis) as a ‘Contraindication.’

The following are the recommendations from the Advisory Committee on Immunization Practices for the 2013-2014 season²:

From the algorithm above, we see that the patient in our vignette should receive the inactivated influenza vaccine (ie. brand names Fluzone®, Fluarix®, Flucelvax®) and be observed for a short time.  She should not receive the RIV3 or the live attenuated influenza vaccine (Flumist®) as she falls outside of the indicated age range.

Eligible patients, even with the most severe reaction from eggs can receive the RIV3 vaccine.  This specific vaccine (brand name Flublok®) contains no egg proteins, antibiotics, or preservatives and can be used at any step of the above algorithm³.

References:

1.  Clark AT, Skypala I, Leech SC, et al.  British Society for Allergy and Clinical Immunology guidelines for the management of egg allergy.  Clinical & Experimental Allergy 2010:40;1116-29.

2.  Summary Recommendations: Prevention and Control of Influenza with Vaccines: Recommendations of the Advisory Committee on Immunization Practices—(ACIP)—United States, 2013-14

Available at: http://www.cdc.gov/flu/professionals/acip/2013-summary-recommendations.htm

3.  Flublok prescribing information.  Protein Sciences. December 2012.