Flu Shot is Safe for Those with Egg Allergies

Matthew Greenhawt, MD, MBA, MSc, lead author of the practice parameter, chair of ACAAI Food Allergy Committee, Children Hospital Colorado, University of Colorado Denver School of Medicine

Matthew Greenhawt, MD, MBA, MSc

According to new government guidelines published in the Annals of Allergy, Asthma and Immunology, the scientific journal of the American College of Allergy, Asthma and Immunology (ACAAI), individuals with an egg allergy no longer need to avoid the flu shot.

In the past, individuals allergic to eggs were advised against the flu vaccination by healthcare practitioners. For some licensed preparations, the viruses were grown in chicken eggs and therefore the vaccine contained trace amounts of egg protein which can induce immediate hypersensitivity reactions. However, the Centers for Disease Control and Prevention (CDC) has since updated their guidelines to state that the vaccine is safe for individuals in this population.

“Egg allergy affects nearly 2% of children, and around 29% of these children may have asthma,” Matthew Greenhawt, MD, MBA, MSc, lead author of the practice parameter, chair of ACAAI Food Allergy Committee, Children’s Hospital Colorado, University of Colorado Denver School of Medicine, told MD Magazine. “Both children and asthmatics are vulnerable populations who are highly recommended to receive annual influenza vaccine, so this subgroup is, in particular, a prime target to protect.”

The practice parameter update makes a strong recommendation indicating that individuals with an egg allergy, regardless of how severe those allergies are, should receive the flu vaccine. The updated recommendations are based on data from more than 2 dozen studies.

“This (vaccination) should be routinely offered in the primary care setting, as per CDC guidelines, to all groups in which annual influenza vaccine is recommended,” Greenhawt said. “This would include children and individuals with asthma, among the numerous individuals who fit the CDC recommendations. There is no need to ask about egg allergy or consider special precautions — these are not necessary. The egg allergic individual should be treated just like any other patient who walks into a provider’s office seeking the vaccine.”

The guidelines are the result of an analysis of 28 studies involving 4,315 egg allergic patients, including 656 patients with a severe egg allergy. The studies showed that those with an egg allergy were no more likely than others to react to a flu shot.

Low rates of minor reactions like hives were noted to occur but at no greater rate than those occurring in the non-egg allergic arm.

“We are now at the point where any remaining contraindication or special precaution is unnecessary, and there should be no barrier to the egg allergic patient receiving this vaccine in the primary care setting, like any patient may,” Greenhawt noted.

While previous parameters stated that those with an egg allergy could safely receive the vaccine at an allergy specialist’s office, followed by a specific waiting period, new parameters, however, state precautions such as specific waiting periods, specific medical settings and choice of vaccination, are not warranted and considered an unnecessary barrier to immunization.

Vaccine providers and screening questionnaires also no longer need to ask about the egg allergy status of vaccine recipients.

“We are now at the point where any remaining contraindication or special precaution is unnecessary, and there should be no barrier to the egg allergic patient receiving this vaccine in the primary care setting, like any patient may,” Greenhawt noted.

Anaphylaxis can rarely occur after the administration of any vaccine to any patient, regardless of allergy at a rate of 1 per million, and therefore it’s recommended that providers are prepared to recognize and manage an adverse reaction.

The practice parameter update was published in the Annals of Allergy, Asthma and Immunology journal, December 2017.