Egg Allergies

For years, health organizations and pediatricians recommended not giving infants (especially those at high-risk) food allergens – like eggs, peanuts, dairy or fish – as an introductory food, and at the same time, pediatricians were noticing an increase in the prevalence of food allergies in U.S. children. Now, current research has challenged that paradigm. Introducing allergen foods as early as 4 months, when the child is developmentally ready, may actually decrease risk of developing food allergies.

Featured article in the Fall 2016 Issue of Nutrition Close-Up; written by Apeksha Gulvady, PhD

Our present decade presents a very different food allergy landscape than it did about 35 years ago in terms of prevalence, types and severity of food-allergic reactions, diagnostic tools, and even recommendations for prevention. Take prevalence in the United States for instance. Although the rates of perceived prevalence have remained at around 20% through the ages, the actual incidence has gradually risen from <1% in the 1980s up to about 5% of the general population and 8% of U.S. children in recent years.^1-4 And while the number of individuals affected by food allergies continues to grow across the globe, particularly in developing countries, the United States alone accounts for as many as 15 million people with food allergies today.¹

Today’s post comes from Chris Barry, PA-C, MMSc. Barry is a nationally certified physician assistant specializing in pediatrics. He is a member of the American Academy of Pediatrics, American Academy of Physician Assistants, North Carolina Academy of Physician Assistants and currently serves as the Medical Liaison from the American Academy of Physician Assistants to the American Academy of Pediatrics. Barry currently serves as one of ENC’s Health Professional Advisors.

It’s hard to believe, but it’s almost that time of year again—flu season. Flu season typically runs from late fall through late winter, but the exact timing can vary from year to year. The safest, most effective method to prevent influenza infection is vaccination. The flu vaccine is recommended for all children, starting at 6 months of age.

There are relatively few contraindications to administering the flu vaccine. The full list of flu vaccine recommendations, dosing and contraindications is listed on the CDC website.

Because most flu vaccines contain residual egg proteins from the manufacturing process, people with egg allergies were previously unable to receive the flu vaccine due to the theoretical concerns of anaphylaxis. This caused many children to not receive this important vaccine.

A 2013 study published in Annals of Asthma, Allergy, and Immunology shows that the flu vaccine can be safely given to children with egg allergies, even those who have severe reactions to eggs (1). Updated guidelines have been issued, stating that children with a history of egg allergy who have experienced only hives after exposure to egg should receive the influenza vaccine. Inactivated or recombinant flu vaccine is recommended for these children, due to lack of data with the live, attenuated nasal flu vaccine. Flu vaccines should be administered in settings, such as their healthcare provider’s office, in which personnel and equipment are available to manage anaphylaxis. Vaccine recipients should be observed for at least 30 minutes for signs of a reaction after administration of each vaccine dose. By one estimate, an additional 150,000-250,000 children would now be eligible to receive the flu vaccine, under the updated guidelines (2).

Children with more severe reactions to eggs, such as anaphylaxis, should be referred to an allergy specialist before vaccine administration. Children with a previous history of severe allergic reaction to the flu vaccine should not receive the flu vaccine.

In summary, a recent study provides strong evidence that egg allergic patients can safely receive the flu vaccine as a single dose without prior vaccine skin testing, provided they are observed for 30 minutes afterward in a medical setting (1).

– Chris Barry, PA-C, MMSc

References:
1. Kelso JM, Greenhawt MJ, Li JT. Update on influenza vaccination of egg allergic patients. Ann Allergy Asthma Immunol. 2013; 111(4):301.
2. Des Roches A, Paradis L, Gagnon R et al. Egg-allergic patients can be safely vaccinated against influenza. J Allergy Clin Immunol. 2012; 130(5):1213-1216.

Researchers in a new preclinical study for Northwestern Medicine have tricked the immune system. They have figured out how to turn off a life threatening allergic response to peanuts (nut proteins). The investigators used mice (that were bred to mimic one with severe food allergies) and attached peanut proteins to leucocytes and reintroduced them into the mice’s bodies. What happened next? The mice ingested a peanut extract and did not have an allergic reaction.

In a second phase of the study, the researchers successfully desensitized mice to egg proteins. The Northwestern researchers used the same tactic with an egg protein. They attached the proteins to white blood cells and infused the cells back into the mice. The mice then inhaled the asthma-provoking egg protein and their lungs did not become inflamed. Dr. Paul J. Bryce, Department of Microbiology-Immunology, Feinberg School of Medicine,noted that it appears that this approach can be used to target multiple food allergies at one time.

Each year there are between 15,000 and 30,000 episodes of food-induced anaphylaxis and 100 to 200 related deaths in the United States, according to the National Institutes of Health. This study may be the link regulating allergic diseases. To quote Dr. Stephen D Miller, the Judy Gugenheim Research Professor at the Feinberg School: “This is an exciting new way in which we can regulate specific allergic diseases and may eventually be used in a clinical setting for patients.”

If this were successful in clinical settings, what would it look like? People with food allergies would not have to worry everyday about coming in contact with the allergen causing food. Also, it would mean that people would be able to enjoy the “allergen causing foods” without risk!