Safe administration of the seasonal trivalent influenza vaccine to children with severe egg allergy

Abstract

BackgroundAnaphylaxis to egg or severe egg allergy has been considered a contraindication to receiving trivalent seasonal influenza vaccine (TIV). ObjectiveTo evaluate the safety of TIV among severely egg allergic children. MethodsA 2-phase, multicenter study at 7 sites was conducted between October 2010 and March 2012. Inclusion criteria included a history of a severe reaction, including anaphylaxis, to the ingestion of egg and a positive skin test result or evidence of serum specific IgE antibody to egg. Phase 1 consisted of a randomized, prospective, double-blind, placebo controlled trial of TIV administration to egg allergic children, using a 2-step approach; group A received 0.1 mL of influenza vaccine, followed in 30 minutes if no reaction with the remainder of an age-appropriate dose, whereas group B received an injection of normal saline followed in 30 minutes if no reaction with the full 100% of the age-appropriate dose. Phase 2 was a retrospective analysis of single dose vs split-dose administration of TIV in eligible study participants who declined participation in the randomized controlled trial. ResultsThirty-one study participants were prospectively evaluated in the randomized controlled trial (group A, 14; group B, 17); 45.1% had a history of anaphylaxis after egg ingestion. A total of 112 participants were retrospectively evaluated (87 with the single dose and 25 with the split dose); 77.6% of participants had a history of anaphylaxis after egg ingestion. All participants in both phases received TIV without developing an allergic reaction. ConclusionTIV administration is safe even in children with histories of severe egg allergy. Use of 2-step split dosing appears unnecessary because a single dose was well tolerated.