From the Guidelines
Patients with egg allergies should avoid the yellow fever vaccine, which is the only vaccine currently contraindicated for this population. While influenza (flu) vaccines were previously of concern, current guidelines indicate that most flu vaccines can be safely administered to people with egg allergies, including those with severe reactions, as stated in the most recent guidelines from 2024 1. The MMR (measles, mumps, rubella) vaccine is also safe for egg-allergic individuals despite being cultured in chicken embryo fibroblasts, as it contains negligible egg protein.
The key consideration for patients with egg allergies is not the type of vaccine but rather ensuring that any vaccination is administered in a setting where personnel and equipment are available to recognize and manage severe allergic reactions, as emphasized in the guidelines 1. For patients who need yellow fever vaccination for travel to endemic areas but have egg allergies, consultation with an allergist for potential desensitization protocols or medical exemption documentation is recommended. Always inform healthcare providers about any allergies before receiving vaccinations.
Some influenza vaccines, such as those that are egg-based (IIV or LAIV), may pose a risk for individuals with a history of severe allergic reactions to eggs, but the latest recommendations suggest that any licensed, recommended influenza vaccine can be used for individuals with egg allergy, with appropriate precautions 1. The guidelines from 2024 provide the most up-to-date recommendations for the use of influenza vaccines in individuals with egg allergies, superseding previous guidelines from 2018 2, 2019 3, and other years.
Given the most recent evidence, the yellow fever vaccine remains the primary concern for individuals with egg allergies due to its production in embryonated chicken eggs and the potential for severe allergic reactions. However, for influenza vaccines, the approach has shifted towards administering any appropriate vaccine with caution and in a medically supervised setting for those with severe egg allergies, as per the latest advisory committee recommendations 1.
From the Research
Vaccination Contraindication in Egg Allergy
- The yellow fever vaccine is contraindicated in patients with egg allergy, as it is propagated in hens' eggs and contains residual egg protein (ovalbumin) 4, 5, 6.
- However, studies have shown that the yellow fever vaccine can be safely administered to egg-allergic patients using a desensitization protocol or a simplified vaccination approach 4, 5, 6.
- In contrast, the trivalent influenza vaccine is no longer contraindicated in egg-allergic individuals, as it has been shown to be safe for patients with egg allergy, including those with severe egg allergy 7.
- Cell culture-based influenza vaccines have emerged as an alternative to egg-based vaccines, but there is insufficient evidence to suggest that they are superior in terms of efficacy or effectiveness 8.