High-Dose Influenza Vaccine for Patients ≥65 Years with Egg Allergy
For patients aged 65 years or older with a history of mild egg allergy (hives only), Fluzone High-Dose is an acceptable option and can be safely administered. 1
Understanding the Vaccine and Egg Content
Fluzone High-Dose is an egg-based, high-dose trivalent inactivated influenza vaccine (HD-IIV3) that contains 60 μg of hemagglutinin per strain—four times the amount in standard-dose vaccines. 1, 2 Like most inactivated influenza vaccines, it is manufactured via propagation of virus in eggs and therefore contains residual egg protein. 1
Current Guidance for Egg Allergy
The Advisory Committee on Immunization Practices (ACIP) has evolved its recommendations regarding egg allergy:
All persons aged ≥6 months with egg allergy should receive influenza vaccine, and any influenza vaccine (egg-based or non-egg-based) that is otherwise appropriate for the recipient's age and health status can be used. 1
For patients with mild egg allergy (specifically those who have experienced only hives following egg exposure), egg-based vaccines including Fluzone High-Dose can be administered without special precautions. 1
The only absolute contraindication is a history of severe allergic reaction (anaphylaxis) to eggs or any vaccine component. 1
Why High-Dose for Patients ≥65 Years
ACIP now expresses a preferential recommendation for higher-dose or adjuvanted influenza vaccines in adults aged 65 years and older. 3, 4 The evidence supporting this includes:
Fluzone High-Dose demonstrated 24.2% relative efficacy over standard-dose vaccine in preventing laboratory-confirmed influenza in a randomized trial of 31,989 persons aged ≥65 years. 3
High-dose vaccine consistently reduces hospitalizations for pneumonia, influenza, cardiorespiratory illnesses, and mortality in elderly populations. 3
The vaccine elicits higher hemagglutination inhibition (HAI) titers against all three influenza virus strains compared to standard-dose vaccines in older adults. 1, 3
Administration Protocol
Fluzone High-Dose is administered as a single 0.5 mL intramuscular injection in the deltoid muscle. 1, 3
Only one dose per influenza season is required. 3
The vaccine is available as a prefilled syringe with no mercury content. 1
Alternative Options if Egg Allergy is Severe
If the patient has a history of anaphylaxis to eggs (not just hives):
Consider Flublok (recombinant influenza vaccine, RIV3), which is manufactured without eggs and contains no egg protein. 1 However, this vaccine is only approved for ages 18-49 years in older guidelines 1, though newer formulations may have expanded age indications.
Flucelvax (cell culture-based vaccine) contains minimal egg protein (<50 femtograms) but cannot be considered completely egg-free and should be used with caution. 1
Common Pitfalls to Avoid
Do not delay vaccination to obtain a specific product when an appropriate one is available. 5 If high-dose vaccine is temporarily unavailable, standard-dose vaccine should be administered. 3
Do not confuse high-dose with standard-dose formulations—verify the product is specifically labeled "Fluzone High-Dose" with 60 μg hemagglutinin per strain. 3
Patients may experience more frequent injection site reactions and systemic symptoms with high-dose vaccine compared to standard-dose, but these are typically mild and transient. 1, 3
Avoid vaccinating in July or August for most adults ≥65 years due to concerns about waning immunity before peak influenza season. 3