Recommendations for using MMR vaccine in children allergic to eggs

Abstract

The measles virus used in the MMR (measles, mumps, rubella) and single measles vaccine is grown in cultures of fibroblasts from chick embryos, and there have been concerns raised about the possible presence of egg protein in the vaccines and the advisability of administration to individuals who are allergic to eggs. We review the evidence for egg as the agent responsible for allergic reactions to MMR or measles vaccine and propose recommendations based on the evidence. The arguments presented also apply to the single mumps vaccine and all other vaccines derived from egg. The recommendations presented have been reviewed and endorsed by the Committee on Infection and Immunisation of the Royal College of Paediatrics and Child Health, and the British Society of Allergy and Clinical Immunology. #### Summary points The majority of life threatening (cardiorespiratory) allergic reactions to MMR vaccine have been reported in children who are not allergic to eggs; these are more likely to be explained by the gelatin or neomycin contained in the vaccine than the ovalbumin MMR vaccine is as safe as any other vaccine, and an allergy to eggs should not delay measles vaccination The only children who need to be vaccinated in hospital are those with an allergy to eggs in whom previous exposure led to cardiorespiratory reactions and those with coexisting active, chronic asthma Children with milder forms of allergy to eggs can be safely vaccinated without additional precautions Any child experiencing an acute allergic reaction to MMR vaccine must have the reaction clearly defined and be evaluated for other allergies References were found by performing a Medline search (for the years 1966-99), which identified 51 references, and by searching issue 3 of the 1999 Cochrane Library , which identified no references. We also reviewed the reference list of each study identified. Thirty four of the …