Study on Influenza Vaccines for Patients with Egg Allergies

Updated Guidelines for the 2017-2018 Flu Season

A recent study has examined the safety of administering influenza vaccines to individuals with egg allergies. As a result of this research, guidelines for the 2017-2018 flu season have been revised. The annual influenza vaccine remains the most effective means of preventing the contraction and spread of the flu virus, which is a significant cause of hospitalization and mortality in North America during flu season.

Understanding Egg Allergies and Vaccine Administration

Not everyone is eligible to receive influenza vaccines, particularly those with egg allergies. Most influenza vaccines are produced using chicken eggs and may contain small amounts of egg protein. Researchers from the Section of Allergy and Clinical Immunology at the Children’s Hospital in Colorado, U.S., conducted a study to assess the safety of these vaccines for patients with egg allergies. Their findings were published in the Annals of Allergy, Asthma, and Immunology.

Research Objectives and Findings

The primary goal of the investigation was to update recommendations regarding the administration of influenza vaccines for patients with egg allergies. The researchers reviewed 28 studies involving over 4,300 individuals with egg allergies, of whom 656 experienced severe anaphylactic reactions to egg ingestion. This analysis led to the development of a detailed approach for administering influenza vaccines to egg-allergic patients, resulting in necessary updates to existing guidelines.

Safety of Influenza Vaccines for Egg-Allergic Individuals

No Increased Risk of Anaphylactic Reactions

The data revealed no significant increase in anaphylactic reactions following influenza vaccine administration among the study participants. While minor reactions did occur, their frequency was consistent with that observed in the general population. In Canada, current guidelines do not mandate special precautions when vaccinating individuals with egg allergies, and there has been no rise in side effects. Consequently, a history of egg allergy is no longer a contraindication for receiving any influenza vaccine, and providers do not need to inquire about egg allergies before vaccination.

Non-Egg Based Vaccines and Anaphylaxis Considerations

During the establishment of new practice recommendations, two additional questions were addressed. Non-egg-based vaccines have been developed for egg-allergic patients, although their use is no longer deemed medically necessary. It is important to note that patients can still experience anaphylactic reactions to these non-egg-based vaccines. Furthermore, the researchers confirmed that all influenza vaccines, including both non-live and live variants, are suitable for individuals regardless of their egg allergy status. Vaccine providers must remain prepared to manage anaphylactic reactions, as is standard practice for any vaccination.

Inclusion of New Recommendations in Guidelines

The updated recommendations have been incorporated into the 2017-2018 influenza guidelines. These guidelines affirm that all influenza vaccines are safe for patients with egg allergies, with no special precautions required during administration. Additionally, non-egg-based vaccines are not medically necessary. However, vaccine providers should continue to be equipped to respond to the rare occurrence of anaphylactic shock after vaccine administration.

Reference

Greenhawt M, Turner PJ, Kelso JM. Administration of influenza vaccines to egg allergic recipients: A practice parameter update 2017. Ann Allergy Asthma Immunol. 2018.