What is the most appropriate influenza vaccination for a patient with a history of hives (urticaria) after consuming egg-containing products, but no history of anaphylaxis?

Influenza Vaccination for Patients with Hives-Only Egg Allergy

Any licensed, age-appropriate influenza vaccine (IIV, RIV4, LAIV4, or ccIIV4) can be administered to this patient without any special precautions beyond standard vaccination protocols. 1

Current ACIP Recommendations

The most recent CDC/ACIP guidelines (2019) have significantly liberalized recommendations for egg-allergic patients compared to earlier guidance. For patients with hives-only reactions to egg:

• Administer any licensed, recommended influenza vaccine that is otherwise appropriate for the recipient's age and health status 1
• No extended observation period is required beyond the standard 15-minute post-vaccination monitoring recommended for all vaccines to assess for syncope 1, 2
• No skin testing is necessary before vaccine administration 1, 2
• No divided-dose protocols are required 1, 2
• The vaccine does not need to be administered by a provider with special expertise in egg allergy 1

Evolution of Guidelines Shows Increasing Safety Data

This represents a substantial change from earlier recommendations. The 2013 ACIP guidelines required IIV (not LAIV), administration by a provider familiar with egg allergy manifestations, and 30-minute observation periods for hives-only patients 1. The 2012 guidelines similarly mandated these additional safety measures 1. These restrictions have been eliminated based on extensive safety data showing no cases of anaphylaxis in large surveillance studies. 1, 3

Available Vaccine Options

Standard Egg-Based Vaccines

• Most IIVs contain ≤1 μg/0.5 mL dose of ovalbumin, which has been well-tolerated in egg-allergic patients 1
• Research studies including over 4,000 patients (513 with severe egg allergy history) reported no occurrences of anaphylaxis 1

Low/No Egg Content Vaccines

• RIV4 (Flublok Quadrivalent): Completely egg-free, manufactured using recombinant technology, approved for ages ≥18 years 1, 2
• ccIIV4 (Flucelvax Quadrivalent): Contains theoretical maximum of 1.7×10⁻⁸ μg/0.5 mL dose of egg protein, approved for ages ≥4 years 1, 2

However, there is no requirement to preferentially use these egg-free or low-egg vaccines for hives-only patients—any age-appropriate vaccine is acceptable. 1, 2

Critical Distinction: More Severe Egg Allergy

For patients who report reactions involving angioedema, respiratory distress, lightheadedness, recurrent vomiting, or who required epinephrine:

• Any licensed, age-appropriate influenza vaccine can still be administered 1
• Must be given in an inpatient or outpatient medical setting (hospital, clinic, health department, or physician office) 1
• Administration must be supervised by a healthcare provider able to recognize and manage severe allergic reactions 1
• This is distinct from the hives-only scenario, where no special setting is required 1

Universal Safety Requirements

All vaccination providers must:

• Be familiar with the office emergency plan 1, 3
• Be certified in cardiopulmonary resuscitation 1
• Have personnel and equipment available for rapid recognition and management of anaphylaxis for all vaccine recipients 1, 3

Common Pitfalls to Avoid

• Do not unnecessarily delay vaccination due to egg allergy concerns when only hives have occurred 2, 4
• Do not perform skin testing for hives-only egg allergy—this is no longer recommended 1, 2
• Do not use divided-dose protocols—these are outdated and not necessary 1, 2
• Do not restrict to egg-free vaccines only—any age-appropriate vaccine is acceptable 1, 2
• Do not confuse egg allergy with vaccine allergy—a previous severe allergic reaction to influenza vaccine itself (regardless of suspected component) remains a contraindication to future influenza vaccination 1, 3

Verification of Hives-Only Status

Confirm that the patient's egg reactions consisted only of urticaria (hives) without:

• Angioedema or swelling 1
• Respiratory distress or wheezing 1
• Lightheadedness or cardiovascular changes 1
• Recurrent vomiting 1
• Need for epinephrine or emergency medical intervention 1

Patients who can eat lightly cooked eggs (e.g., scrambled eggs) without reaction are unlikely to be truly allergic, though tolerance to baked egg products does not exclude the possibility of egg allergy 1