Safe Administration of Flu Vaccine to Egg Allergic Children

Historically, providing influenza vaccination of egg allergic children and young adults (EAC) with a history of anaphylaxis to egg, or other severe symptoms of an allergic reaction to egg (e.g., severe hives, swelling, or asthma), has been contra-indicated, though vaccination of children with less severe egg allergy has been shown to be safe. Though many children with severe egg allergy, including anaphylaxis, have received past influenza vaccination anecdotally, very few data exist to show this procedure is safe. The investigators propose a double blind, placebo-controlled randomized, prospective multi-centered study to a) demonstrate seasonal trivalent influenza vaccine (TIV) can be safely given in a single dose (as opposed to through 2-step graded dosing of 10% then 90% of the vaccine dose) to EAC despite history of anaphylaxis or previous severe allergic reaction to egg; and b) provide further evidence that adverse outcomes are not related to ovalbumin (egg) content in TIV. Study participants must have a documented history of a severe egg allergy, substantiated by both a history of clinical reactivity AND either a positive skin test or ImmunoCAP/RAST test greater than 0.7 kUA/L. Participants will be randomized to receive either a 2-step graded challenge or a single dose given after a small placebo dose of saline (to mimic the graded challenge). If required, all participants will receive a booster vaccination as a single dose.