Allergic Reactions to MMR Vaccines in Egg- and Non-Egg-Sensitive Children: A Continuing Controversy

Abstract

Measles vaccines prepared in chick embryo fibroblast culture have been used since 1963. Since then, dramatic reductions of the incidence of measles have been observed where the vaccination was extensively applied in the pediatric population, with the best results observed in the initial phase when the target population was that producing over 90% of cases in the prevaccinal era. Since the virus vaccine is grown in cultures of chicken fibroblast cell, although egg proteins could not be found in vaccines, a possible limiting factor to the diffusion of measles vaccination is represented by the assumption that allergy to egg proteins contraindicates the vaccination. It is known that there is a controversy in the literature about the safety of measles vaccine and measles, mumps, and rubella vaccine (MMR) in eggallergic children. Recent data suggest that reactions to MMR vaccine can be mediated by gelatin and/or neomycin. In this paper, current knowledge on the safety of measles immunization in children with and without egg allergy is discussed. In addition, we propose that all children to be immunized with MMR vaccine and their families should be questioned about neomycin and related antibiotic allergy.