Abstract:
Background: Immediate type hypersensitivity to vaccines containing bovine/porcine excipients, such as
the measles, mumps and rubella (MMR) vaccine is probably due to sensitization to bovine/porcine gelatin.
Most patients with such reactions in Sri Lanka have cow’s milk (CM) or beef allergy.
Objectives: We investigated whether those who had beef and CM allergy had a higher incidence of hypersensitivity
reactions to vaccines and the possible trigger of such reactions.
Material and methods: Twenty patients with immediate type hypersensitivity reactions to vaccines containing
bovine/porcine excipients, controls with allergy to beef/pork (n = 11) or CM (n = 11), and 8 non
atopic controls were recruited. Total serum IgE, specific IgE to beef, CM, casein, beta lactoglobulin, gelatin
and bovine serum albumin (BSA) by Phadia ImmunoCap and IgE to porcine gelatin by Western blot were
evaluated.
Results: 11/20, 5/20, 2/20, 2/20, 1/20 and 1/20 patients reported allergic reactions to measles containing,
JE, rabies primary chick embryo, pentavalent, diphtheria and tetanus, and adult diphtheria and tetanus
vaccines, respectively. Only one patient with allergy to vaccines had gelatin specific IgE, whereas IgE
to BSA was seen in 73.3%, 90%, 66.6% and 0 of vaccine, beef or CM allergic and non-atopic controls, respectively.
The mean IgE to BSA was higher in patients with allergy to vaccines, although not significant.
Specific IgE to BSA was present in 54.7% of children with allergy to CM, of whom 11.8% had high levels
(>17.5 kUA/L). In contrast, 66.6% of these children did not have specific IgE to b-lactoglobulin, which is
one of the major components of whey protein.
Conclusion and clinical relevance: Gelatin does not appear to play a major role in Sri Lankan children with
allergy to vaccines. In contrast, due to the higher levels of BSA specific IgE, sensitization to BSA is possibly
playing a role.
