Clinical and laboratory observation

Safe administration of mumps-measles-rubella vaccine in egg-allergic children1,2

Excipients are substances in pharmaceuticals other than the active ingredients. Some excipients are foods or substances derived from foods, raising the possibility that these substances would pose a hazard to patients with food allergy. This review describes which food-derived substances are used as pharmaceutical excipients in which medications and reviews published data regarding the safety of the administration of these medications to recipients with food allergy. Such reactions are rare, usually because the amount of food protein is not present in a large enough quantity to elicit a reaction. When a food protein appears as an unintentional contaminant, the amount, if any, that is present might be variable and might elicit reactions only from some lots of medication or only in some patients. In most circumstances these medications should not be routinely withheld from patients who have particular food allergies because most will tolerate the medications uneventfully. However, if a particular patient has had an apparent allergic reaction to the medication, potential allergy to the food component should be investigated.

La rubéole est une maladie virale bénigne de l’enfance. Cependant, lorsqu’une femme contracte la maladie au cours de la grossesse, les conséquences peuvent être dramatiques pour le fœtus, surtout si l’infection survient au cours du 1^er trimestre. La sévérité de cette maladie justifie donc sa prévention par la vaccination. En France, la recommandation de vaccination généralisée des enfants à partir de 1986 avec le vaccin trivalent rougeole-oreillon-rubéole a permis une diminution majeure de l’incidence des infections en cours de grossesse et des rubéoles congénitales. Cependant, l’objectif de l’OMS Europe d’éliminer la rubéole congénitale en 2010 n’étant pas atteint en France, les efforts pour augmenter la couverture vaccinale des enfants des deux sexes et améliorer le rattrapage des jeunes femmes en âge de procréer doivent être maintenus.

Rubella is a mild viral disease in childhood. Unfortunately, when a woman contracts the disease during pregnancy, the consequences can be dramatic for the fetus, especially if infection occurs during the first trimester. The severity of congenital rubella syndrome justifies its prevention through widespread vaccination. The introduction of vaccination in children of both sexes in 1986 in France with a trivalent measles-mumps-rubella vaccine dramatically reduced the incidence of maternal infection during pregnancy as well as that of congenital rubella infection. However, as the objective of WHO Europe to eliminate congenital rubella in 2010 has not been achieved, efforts to increase vaccination coverage in children of both sexes and to improve immunization of women of childbearing age must be maintained.

Since the measles and mumps components used in MMR vaccine are grown in cultures of fibroblast from chick embryos, for a long time there have been concerns about the presence of egg protein in the vaccine and the recommendations given to egg allergic patients.

We include in this paper our clinical experience vaccinating egg allergic patients with a regular triple viral vaccine, as well as an immunological study of each vaccine available in Spain. The aim of this study was to evaluate the clinical safety of a conventional MMR vaccine in a population of egg allergic patients and to determine the presence of egg allergens in a conventional MMR vaccine and if IgE antibodies from egg allergic can recognize egg allergens in this vaccine

Children 15 months old with a confirmed diagnosed of egg allergy were included.

In all patients, a skin prick test with non diluted MMR vaccine (Priorix, GSK) was made.

If negative, each patient received a single dose of measles, mumps, rubella (MMR) vaccine. If positive, a fractionated injection of the vaccine was made following SEICAP recommendations (2004).

SDS-PAGE immunoblotting was performed with Priorix vaccine.

A cumulative total of 26 patients with egg allergy have safely received MMR vaccine in a single-dose (after a negative SPT in all cases) at our department without any reaction.

5 sera of vaccinated patients and 6 control sera of egg allergic patients (positive oral challenge) were used to immunolabel the membranes. No positive bands corresponding to egg proteins were found in any of the patients.

Negative results found in SPT support the absence of clinical reaction against the components and Immunological studies point that there is no detectable amount of egg protein in this vaccine to produce an IgE mediated reaction. We can conclude that MMR can be safely administrated in children allergic to egg.

En España la alergia al huevo se ha considerado durante mucho tiempo una contraindicación de la administración de vacunas incubadas en células de embrión de pollo, como la triple vírica o la antigripal. Por ese motivo, en niños alérgicos al huevo, se ha indicado sistemáticamente una vacuna alternativa (Triviraten(r)) incubada en células diploides humanas, sin plantear si podrían tolerar la vacunación SaRuPa (Sarampión-Rubéola-Parotiditis) estándar.

Tras el cese de la producción de Triviraten(r) por parte del Laboratorio Biotech Berna se ha eliminado dicha alternativa para niños con alergia al huevo, que deben recibir la primovacunación a los 15 meses y una dosis de recuerdo a los 3 años, de acuerdo con el calendario vacunal vigente en la actualidad.

En este contexto, durante el período noviembre 2004-junio 2005 se realizó vacunación triple vírica convencional en 40 niños alérgicos al huevo, sin que ninguno de ellos presentase reacción adversa tras su administración, por lo que se puede concluir que esta es segura en el citado grupo de pacientes.

In Spain, for many years allergy to eggs was considered to contraindicate vaccines cultured in fibroblasts from chick embryos such as the measles, mumps, rubella (MMR) and influenza vaccines. Consequently, an alternative vaccine (Triviraten Berna^®) incubated in diploid human cells has been systematically administered to children who are allergic to eggs, without questioning tolerance to the standard MMR vaccine.

After Biotech Bern Laboratory discontinued the production of Triviraten^®, this alternative was no longer available for children with egg allergy, who should receive a first dose of the MMR vaccine at the age of 15 months and a second one (booster dose) at the age of 3 years.

In this context, from November 2004 to June 2005, a single dose of the MMR vaccine was administered to 40 children with allergy to eggs and none showed an adverse reaction. We conclude that this vaccine can be safely administered to this group of patients.