Safe administration of influenza vaccine to patients with egg allergy

Specific recommendations for administering the influenza vaccine to patients with egg allergy are based on limited scientific data. The objectives of this investigation were to determine the safety of a 2-dose administration of an influenza vaccine to patients with egg allergy and to evaluate the usefulness of skin testing with the influenza vaccine before administration.

In this multicenter clinical trial, clinical histories of egg allergy were confirmed by skin testing with egg and, if possible, by oral challenges with egg. Subjects with egg allergy received the vaccine in 2 doses, 30 minutes apart; the first dose was one tenth and the second dose nine tenths of the recommended dose as determined by age. Subjects without egg allergy were recruited as control subjects and received 1 age-determined dose of the vaccine. Skin prick tests with the influenza vaccine were performed on all subjects.

From 1994 to 1997, 83 subjects with egg allergy and 124 control subjects were evaluated. The content of ovalbumin/ovomucoid was 0.1, 1.2, and 0.02 micrograms/mL, respectively in the 1994-95, 1995-96, and 1996-97 influenza vaccines. Results of vaccine skin prick tests were positive in 4 subjects with egg allergy and in 1 control subject. All patients with egg allergy tolerated the vaccination protocol without any significant allergic reactions.

These results demonstrate that patients with egg allergy, even those with significant allergic reactions after egg ingestion, can safely receive an influenza vaccine in a 2-dose protocol when the vaccine preparation contains no more than 1.2 micrograms/mL egg protein.