Are there any vaccines that should not be administered concurrently with the seasonal influenza vaccine?

No Absolute Contraindications for Concurrent Vaccination with Flu Vaccine

There are no vaccines that are absolutely contraindicated to give with the flu vaccine—you can safely administer influenza vaccines concurrently with virtually all other vaccines, both inactivated and live. The key distinction is in timing requirements for live vaccines when not given simultaneously.

General Principles for Concurrent Administration

Inactivated Influenza Vaccines (IIV) and Recombinant Vaccines (RIV)

• Can be given simultaneously or sequentially with ANY other vaccine (inactivated or live) 1, 2, 3
• Administer injectable vaccines at separate anatomic sites 1, 3
• No waiting period required between doses

Live Attenuated Influenza Vaccine (LAIV)

• Can be given simultaneously with other live or inactivated vaccines 1
• Critical timing rule: If LAIV and another live vaccine are NOT given on the same day, wait at least 4 weeks before administering the second live vaccine 4, 1, 3
• This 4-week spacing requirement applies to live vaccines like MMR, varicella, and live zoster vaccine

Specific Vaccine Combinations Studied

Well-Established Safe Combinations

The following have demonstrated safety and adequate immunogenicity when co-administered with influenza vaccines:

In Adults:

• Pneumococcal vaccines (PCV13, PPSV23) 1, 5
• Tdap (tetanus, diphtheria, pertussis) 1
• Zoster vaccines (both live attenuated and recombinant) 6, 1, 5
• COVID-19 mRNA vaccines 2, 7, 8

In Children:

• MMR and varicella vaccines with LAIV 4, 1
• PCV13 with IIV 1
• DTaP-containing vaccines with IIV 1

Important Caveats and Clinical Considerations

Increased Reactogenicity (Not Contraindications)

While safe, certain combinations may increase side effects:

Young Children (6-23 months):

• Co-administration of IIV with PCV13 increases fever risk on days 0-1 post-vaccination 1, 5
• Increased febrile seizure risk when IIV given with PCV7, PCV13, or DTaP vaccines 1
• These are NOT contraindications—febrile seizures are brief with good prognosis, and ACIP made no changes to recommendations 1

Adults:

• Injection site reactions more common with concurrent administration but generally mild-moderate 1
• When giving two adjuvanted vaccines (e.g., high-dose flu vaccine with Shingrix), consider administering in different limbs 3

Novel Adjuvanted Vaccines

For vaccines with newer adjuvants (AS01B in Shingrix, MF59 in Fluad, AS01E in Arexvy):

• Limited data on co-administration of multiple adjuvanted vaccines 1, 3
• You may consider selecting a non-adjuvanted flu vaccine when giving another adjuvanted vaccine simultaneously to potentially reduce reactogenicity 1, 3
• However, do not delay vaccination if a specific product is unavailable 1, 3
• Most reactogenicity resolves within 4 days 1, 3

Potential Immunologic Interference (Clinically Uncertain)

Some studies show reduced antibody responses to certain antigens when co-administered with IIV:

• PCV13 1, 5
• Tetanus and pertussis antigens 1
• One influenza B antigen when PPSV23 given with IIV4 (resolved by 6 months) 2, 5

Clinical significance is uncertain in most cases—these findings have not changed ACIP recommendations 1, 5

The Only True Restriction: Influenza Antivirals with LAIV

This is about medications, not vaccines, but worth noting:

• Influenza antivirals (oseltamivir, zanamivir, peramivir, baloxavir) can interfere with LAIV replication 4, 9, 2
• Do not give LAIV within 48 hours after stopping oseltamivir/zanamivir 4, 9
• Avoid LAIV from 5 days before to 14 days after peramivir, or 17 days before to 14 days after baloxavir 2
• This does NOT apply to inactivated flu vaccines (IIV/RIV), which can be given with antivirals 4, 9, 2

Practical Algorithm

For any patient receiving flu vaccine:

1. Identify vaccine type: Inactivated (IIV/RIV) or Live (LAIV)?

2. For IIV/RIV: Give with any other needed vaccine on the same day

   • Use separate injection sites
   • If giving multiple adjuvanted vaccines, use different limbs when possible

3. For LAIV:

   • Give with any other needed vaccine on the same day, OR
   • If another live vaccine needed but not given today, schedule it ≥4 weeks later
   • Ensure no influenza antivirals given 48 hours before to 14 days after

4. Counsel patients: Expect potentially increased local reactions or fever with concurrent administration, especially in young children with PCV13