For years, people with an egg allergy have been told to avoid or take special precautions when getting a flu shot because most influenza vaccines are grown in eggs and contain a tiny amount of egg protein. An updated practice parameter from the Joint Task Force on Practice Parameters stresses that people with egg allergy should receive their yearly flu shot, and that no special precautions are required. The guidelines are published in Annals of Allergy, Asthma and Immunology, the scientific journal of the American College of Allergy, Asthma and Immunology (ACAAI).
"When someone gets a flu shot, health care providers often ask if they are allergic to eggs," says allergist Matthew Greenhawt, MD, chair of the ACAAI Food Allergy Committee and lead author of the practice parameter. "We want health care providers and people with egg allergy to know there is no need to ask this question anymore, and no need to take any special precautions. The overwhelming evidence since 2011 has shown that a flu shot poses no greater risk to those with egg allergy than those without."
There have been dozens of studies involving thousands of patients with egg allergy who have received a flu shot without allergic reactions – including hundreds with life-threatening egg allergy. This is because the influenza vaccine does not contain enough egg protein to cause an allergic reaction, even in patients with severe egg allergy. Prior practice parameters noted this and recommended that egg allergic patients could safely receive their vaccination at an allergist's office.
The updated parameter stresses that no special precautions are needed or recommended for those with egg allergy. There is no longer a need to:
- See an allergy specialist for the flu shot.
- Give special flu shots that don't contain traces of egg.
- Require longer-than-normal observation periods after the shot, or
- Even ask about egg allergy before giving the vaccine.
If the vaccine is age-appropriate, it can be used for anyone with or without egg allergy.
These recommendations from the allergy community are consistent with those from the Centers for Disease Control and Prevention and the American Academy of Pediatrics, all emphasizing the safety and importance of egg-allergic patients receiving their annual influenza vaccine.
"There are hundreds of thousands of hospitalizations, and tens of thousands of deaths in the United States every year because of the flu, most of which could be prevented with a flu shot," says allergist John Kelso, MD, ACAAI member and co-author of the practice parameter. "Egg allergy primarily affects young children, who are also particularly vulnerable to the flu. It's very important that we encourage everyone, including children with egg allergy, to get a flu shot."
One of the main concerns with any vaccine is a severe allergic reaction – known as anaphylaxis. Anaphylaxis can happen with any vaccine at a rate of about one per million, no matter the type or whether the person has an allergy. That is why it is always recommended that all personnel and facilities providing vaccines have procedures in place for responding to this rare event.