Flu vaccines and egg allergies were thought for years to be incompatible, since the vaccine is made with an egg-based process. But here's some good news for those allergic to eggs: If you get the flu vaccine, chances are you'll be just fine.
A new study shows that, indeed, most people with egg allergies can receive the flu vaccine. The issue is important because public health experts now urge just about everyone, from children ages six months and older to seniors, to get vaccinated against the flu. About 1.5 percent of U.S. kids—around one million—have an egg allergy.
In recent years the federal government has been attempting to ease fears that the flu vaccine is unsafe for most people with egg allergies. But it has sometimes been a tough sell, since many have justifiable fears of severe— even life-threatening—reactions to the vaccine.
The new study, published online recently in the Journal of Allergy and Clinical Immunology, put the question to a direct test. Researchers followed 367 people, mostly kids, with egg allergies who got a flu shot. About one-third of the study participants had a serious egg allergy, meaning they had a history of developing anaphylaxis after eating eggs.
Anaphylaxis is a severe reaction that often involves having trouble breathing, plus nausea and rash. But in the study, none of those supposedly high-risk individuals had a reaction to the flu shot. Among the 367 people, only 13 had mild symptoms after the shot, such as hives or itchy skin.
The authors of the report, from Hospital Sainte-Justine in Montreal, also looked at other studies on flu shots and egg allergy. Among 4,000 people examined in 26 studies, none had a serious allergic reaction to the flu shot.
The study adds to a growing body of research that's easing fears about egg allergies and the flu vaccine.
"Pediatricians used to just tell the parents of these kids, 'You have an egg allergy. You can't get the vaccine,' " Dr. Clifford Bassett, a fellow of the American College of Allergy, Asthma and Immunology, told TakePart (Bassett was not involved in the study). "But the key is to work with your allergist. The concern has been reduced significantly over the last five years. We're seeing a definite disadvantage, especially in years with swine flu outbreaks and other variants, where there is a real risk to pediatric patients by not getting the vaccine."
Flu vaccines today contain only a trace of egg protein, not enough to trigger a reaction, he says. But the quantity of egg protein in vaccines can vary. People who are concerned can ask their healthcare provider to check the vaccine's egg protein quantity, which is provided on the package labeling.
"There is less egg protein in these vaccines than ever before," says Bassett, who practices at Allergy & Asthma Care of New York and is a clinical assistant professor at New York University School of Medicine. "A board-certified allergist can find a brand that has the lowest amount of egg allergen."
Health professionals typically ask, "Are you allergic to eggs?" before administering a flu shot. But that question likely deters too many people from getting the vaccine, experts say. Instead, health professionals should ask how severe the egg allergy is, the authors of the study suggest.
According to updated recommendations for flu vaccinations from the Centers for Disease Control and Prevention, people with a prior severe allergic reaction to the vaccine should avoid the shot. But people who have only hives following the shot can get vaccinated. People who have had severe reactions to eating eggs—such as trouble breathing or the need for emergency medical care—should talk to a doctor with expertise in allergic conditions before getting a flu shot
People with known egg allergies should receive the flu vaccine by a healthcare professional who is prepared to handle an allergic reaction, Bassett says. These patients should be observed for at least 30 minutes following vaccination to make sure they can be treated in the case of a severe allergic reaction.
The CDC does not advise that people get an allergic skin test to see if they can tolerate the vaccine. Another approach to vaccinating people with egg allergies is to split the vaccine and deliver it in two doses. But the CDC says that's not necessary.
It's also helpful to know if you really are allergic to eggs. People who can eat lightly cooked egg, such as scrambled eggs, are not likely to react to a flu vaccine. Egg allergy can be confirmed by a skin test or blood test or immunoglobulin E antibodies to egg proteins. Most children outgrow egg allergies by ages 5 or 6, Bassett says.
Have you been hesitant to get a flu shot this year? Let us know in the comments.