Can a flu (influenza) booster be administered to an infant who is not feeling well?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: March 25, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

From the Guidelines

It's generally not recommended to give a flu vaccine to an infant who is not feeling well, especially if they have a moderate to severe illness with or without fever. Minor illnesses like a mild cold with low-grade fever, ear infection, or mild diarrhea are usually not reasons to postpone vaccination. However, if your infant has a more significant illness with fever, it's best to wait until they recover before administering the flu vaccine. This recommendation exists for two main reasons: first, symptoms of illness might be incorrectly attributed to the vaccine rather than the underlying condition; second, the immune response to the vaccine might not be optimal if the body is already fighting an infection. If your infant is scheduled for a flu vaccine but isn't feeling well, contact their healthcare provider who can assess their condition and advise whether to proceed with vaccination or reschedule. The flu vaccine is important protection for infants, who are at higher risk for complications from influenza, so it should be given as soon as it's appropriate to do so 1.

Some key points to consider:

  • The American Academy of Pediatrics recommends annual influenza vaccination of all children without medical contraindications starting at 6 months of age 1.
  • Antiviral treatment of influenza is recommended for children with suspected or confirmed influenza who are hospitalized or have severe or progressive disease or have underlying conditions that increase their risk of complications of influenza, regardless of duration of illness 1.
  • The benefits of influenza vaccination might outweigh the risks for certain people who have a history of Guillain-Barré syndrome and who also are at high risk for severe complications from influenza 1.

In terms of morbidity, mortality, and quality of life, the most recent and highest quality study suggests that influenza vaccination is an important strategy for protecting children and the broader community as well as reducing the overall burden of respiratory illnesses 1. Therefore, it is essential to follow the recommendations of the American Academy of Pediatrics and consult with a healthcare provider to determine the best course of action for an infant who is not feeling well and is scheduled for a flu vaccine.

From the Research

Administration of Flu Booster to Infants

  • The American Academy of Pediatrics recommends annual influenza vaccination of all children without medical contraindications starting at 6 months of age 2, 3.
  • Any licensed influenza vaccine appropriate for age and health status can be administered, ideally as soon as possible in the season, without preference for one product or formulation over another 2, 4.
  • There is no specific guidance that prohibits the administration of a flu booster to an infant who is not feeling well, but the decision to vaccinate should be made on a case-by-case basis, considering the infant's overall health and medical history 2, 3, 4.
  • Antiviral treatment of influenza with any US Food and Drug Administration-approved, age-appropriate influenza antiviral medication is recommended for children with suspected or confirmed influenza who are hospitalized, have severe or progressive disease, or have underlying conditions that increase their risk of complications of influenza, regardless of duration of illness 2, 3.

Special Considerations

  • Influenza vaccination is an important strategy for protecting children and the broader community, as well as reducing the overall burden of respiratory illnesses when other viruses, including severe acute respiratory syndrome-coronavirus 2, are cocirculating 2, 4.
  • The effectiveness of influenza vaccines is related predominantly to the age and immune competence of the vaccinee and the antigenic relatedness of vaccine strains to circulating strains 5.
  • Guidance for vaccine planning during the pandemic is available, and recommendations for the use of COVID-19 vaccines are available 4.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Prevention and Control of Seasonal Influenza with Vaccines: Recommendations of the Advisory Committee on Immunization Practices, United States, 2021-22 Influenza Season.

MMWR. Recommendations and reports : Morbidity and mortality weekly report. Recommendations and reports, 2021

Research

Seasonal influenza vaccines.

Current topics in microbiology and immunology, 2009

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.