Most influenza vaccines are grown in the embryos of chicken eggs, and traditional practice has meant that people who have allergies to eggs could not get the flu vaccine.

But a new practice parameter update published today in the Annals of Allergy, Asthma and Immunology finds there is so little of the protein ovalbumin in the vaccine that egg-allergy sufferers can safely get the vaccines.

“Egg allergic patients can be vaccinated safely with influenza vaccines in the same manner as those without egg allergy,” write the doctors, from a cross-section of a dozen top medical school in the country.

The Influenza Vaccine and Egg Allergy Practice Parameter Workgroup developed the recommendations for the Joint Task Force on Practice Parameters.

The group looked at 38 studies, including data from 4,315 patients with an egg allergy (656 of whom had severe allergies).

Low rates of minor reactions such as hives were reported, they write.

However, since as much as two percent of the children in the U.S. have egg allergies – and 29 percent of those have asthma – the vaccines are an aggregate benefit, they conclude. Some 23,000 people die in the U.S. each year as a result of the flu, mostly vulnerable parts of the population who are either very young or very old.

“There is strong evidence that egg allergic individuals can safely receive (inactivated influenza vaccine) or (live attenuated influenza vaccine) if the latter vaccine is recommended for use once the concerns regarding efficacy have been resolved,” they write. “Presence of egg allergy in an individuals is not a contraindication to receive IISV or LAIV. Influenza vaccine recipients with egg allergy are at no greater risk for a systemic allergic reaction than those without egg allergy.”

The risk of anaphylaxis for any patient receiving any vaccine is roughly one in 1 million, the authors contend.