Yes. Influenza vaccination is especially important during pregnancy because pregnant people are at increased risk for influenza-related complications and infants are at increased risk during the first 6 months of life.
CDC and the American College of Obstetricians and Gynecologists (ACOG) recommend influenza vaccination during any trimester. An age-appropriate inactivated or recombinant influenza vaccine as soon as it is available; FluMist (LAIV) should not be given during pregnancy. ACOG and CDC recommend that vaccination during July or August may be considered during the third trimester, and vaccination should continue while influenza viruses are circulating. The American Academy of Pediatrics (AAP) recommends annual influenza vaccination for all children age 6 months and older, including pregnant adolescents. See ACOG’s 2026 clinical guidance for influenza vaccination www.acog.org/clinical/clinical-guidance/practice-advisory/articles/2025/08/influenza-in-pregnancy-prevention-and-treatment and AAP’s 2026 influenza vaccination policy statement at https://doi.org/10.1542/peds.2026-078778.
Last reviewed:
October 11, 2026
Last reviewed:
January 9, 2026
Last reviewed:
September 3, 2025
CDC and the American Academy of Obstetricians and Gynecologists (ACOG) recommend influenza vaccination during any trimester because pregnant people are at increased risk for influenza complications and hospitalization. Infants younger than age 6 months are too young to be vaccinated. Vaccination during pregnancy produces antibodies that cross the placenta and help protect the infant during the first months of life. CDC and ACOG recommend an age-appropriate inactivated or recombinant influenza vaccine during pregnancy. See ACOG’s clinical practice guidance for vaccination at www.acog.org/clinical-information/maternal-immunization-schedule.
Last reviewed:
October 11, 2026
CDC, the American Academy of Pediatrics (AAP) and the American College of Obstetricians and Gynecologists (ACOG) recommend any age-appropriate inactivated or recombinant influenza vaccine during pregnancy and recommend against FluMist because it is a live vaccine. The newest influenza vaccine, mFlusiva by Moderna (an mRNA platform vaccine) is approved for use in people age 50 years and older. It is not licensed or recommended for use during pregnancy because of an absence of data on its use during pregnancy.
A June 2025 ACIP vote to recommend only thimerosal-free influenza vaccines was paused by a federal court stay in March 2026 and is not in effect. See ACOG’s clinical practice guidelines for immunization at www.acog.org/clinical-information/maternal-immunization-schedule. See AAP’s 2026 influenza vaccination policy statement https://doi.org/10.1542/peds.2026-078778.
Last reviewed:
October 11, 2026
Yes. A June 2025 ACIP vote to recommend only thimerosal-free influenza vaccines was paused by a federal court stay in March 2026 and is not in effect. Among 2026–27 influenza products, only Fluzone has a packaging option of a multidose vial containing thimerosal. The American College of Obstetricians and Gynecologists (ACOG) and the American Academy of Pediatrics (AAP) recommend an age-appropriate inactivated or recombinant influenza vaccine during pregnancy without a preference based on thimerosal. A few states restrict its use during pregnancy; check current state requirements.
Last reviewed:
October 11, 2026
No. CDC and medical societies do not routinely recommend more than one dose of influenza vaccine per season, except for certain children being vaccinated for the first time.
Last reviewed:
October 11, 2026
A CDC-funded study found that people who had been vaccinated early in pregnancy with an influenza vaccine containing the pandemic H1N1 (H1N1pdm09) component and who also had been vaccinated the prior season with an H1N1pdm09-containing influenza vaccine had an increased risk of spontaneous abortion (miscarriage) in the 28 days after vaccination. This study did not quantify the risk of miscarriage and did not prove that influenza vaccine was the cause of the miscarriage. Earlier studies have not found a link between influenza vaccination and miscarriage. A larger follow-up study also funded by CDC which included 3 more years of data found no association between early miscarriage and influenza vaccination regardless of previous influenza season vaccination. These results are reassuring regarding the safety of influenza vaccination during pregnancy.
CDC, the American Academy of Pediatrics (AAP), and the American College of Obstetricians and Gynecologists (ACOG) all recommend influenza vaccination during any trimester of pregnancy. Influenza poses a danger during pregnancy and the vaccine can prevent influenza in pregnant people and their infants.
Last reviewed:
October 11, 2026
The American Academy of Pediatrics (AAP) recommends any licensed influenza vaccine appropriate for a child’s age and health status, without preference for a product or formulation with or without thimerosal. A June 2025 ACIP vote to recommend only thimerosal-free influenza vaccines was paused by a federal court stay in March 2026 and is not in effect. Some states restrict thimerosal-containing vaccines; check current state requirements.
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October 11, 2026
People with a metabolic disease, including diabetes, should receive annual influenza vaccination with an age-appropriate inactivated, mRNA, or recombinant influenza vaccine.
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October 11, 2026
Yes. People with multiple sclerosis should be vaccinated against influenza. Multiple sclerosis is not a contraindication to any vaccine, including influenza vaccines.
Last reviewed:
October 11, 2026
Although some studies have demonstrated a transient increase in replication of HIV following inactivated influenza vaccine, other studies have not found this. This temporary increase in HIV titer has not been associated with deterioration in either T-lymphocyte counts or clinical condition. Annual influenza vaccination with an age-appropriate injectable influenza vaccine benefits HIV-infected people.
Last reviewed:
October 11, 2026
In November 2015, FDA licensed Fluad (aIIV, CSL Seqirus), an MF59-adjuvanted inactivated influenza vaccine, for people age 65 years and older. Fluad is the first adjuvanted influenza vaccine marketed in the U.S. An adjuvant is a substance added to a vaccine to increase the immune response to vaccination. The MF59 adjuvant is based on squalene, an oil that occurs naturally in many plants and animals. Fluad has been used in Europe since 1997 and is approved in many other countries. In contrast to Fluzone High-Dose (HD-IIV, Sanofi), Fluad is a standard-dose vaccine, containing 15 mcg of hemagglutinin per virus per dose.
Last reviewed:
October 11, 2026
Yes. CDC preferentially recommends Flublok, Fluad, or Fluzone High-Dose for adults age 65 years and older. If none is available, CDC recommends giving any age-appropriate influenza vaccine rather than delaying vaccination. The American Academy of Family Physicians (AAFP) recommends those three products and the mFlusiva mRNA vaccine preferentially for this age group.
Last reviewed:
October 11, 2026
Although Fluzone High-Dose (HD-IIV) and Fluad (aIIV) are FDA-licensed for people 65 years and older, in June 2024, ACIP recommended that HD-IIV or aIIV are options for administration to people age 18 through 64 years old who have had a solid organ transplant (SOT) and are on immunosuppressive medication regimens. ACIP expressed no preference for HD-IIV or aIIV over any other age-appropriate IIV or RIV vaccines for SOT recipients.
Last reviewed:
October 11, 2026
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September 3, 2025
No, and this is not recommended.
Last reviewed:
October 11, 2026
People with cancer need protection from influenza. CDC and IDSA recommend an age-appropriate 2026–27 influenza vaccine for immunocompromised adults and children. Inactivated, cell culture-based, recombinant, and mRNA vaccines may be options when age-appropriate; IDSA and CDC recommend against FluMist for immunocompromised people. IDSA notes that data on mRNA influenza vaccine in immunocompromised people are limited at this time. See www.idsociety.org/practice-guideline/Seasonal-RTI-Vaccinations-in-Immunocompromised-Patients/.
Last reviewed:
October 11, 2026
AAP provided additional details about timing and product choices for influenza vaccination of immunocompromised children in its 2026 influenza vaccination policy statement (see https://doi.org/10.1542/peds.2026-078778). All immunocompromised children should be vaccinated with an age-appropriate inactivated influenza vaccine (IIV) or recombinant influenza vaccine (RIV), preferably before the start of influenza season. Household contacts also should be vaccinated. The additional considerations from AAP concerning timing and product choice are listed below:
- For children with malignancy receiving chemotherapy, administer IIV or RIV 2 weeks or more before cytotoxic chemotherapy when possible.
- For children receiving immunosuppression for underlying autoimmune or autoinflammatory conditions, administer IIV or RIV 2 weeks or more before starting these therapies when possible.
- For children who will be starting anti-B cell therapies (e.g., rituximab, alemtuzumab), administer IIV or RIV 2 weeks or more before starting these therapies when possible.
- For children who have received B-lymphocyte–depleting therapies, consider IIV or RIV 3 to 6 months after last dose; earlier vaccination could be considered if influenza is circulating in the community.
- For children who have received CD19-targeted chimeric antigen receptor T-lymphocyte infusions (CAR-T), consider IIV or RIV 3 to 6 months after CAR-T in patients who are in remission and do not require additional intensive chemotherapy or hematopoietic cell transplant (HCT).
- For HCT recipients, consider IIV or RIV starting 3 months after HCT.
- Consider administering 2 doses of high-dose IIV 28 to 42 days apart in pediatric HCT recipients 3 to 17 years of age in the first year after HCT, recognizing that high-dose IIV is not approved for use in children.
- For solid organ transplant (SOT) recipients 6 months through 17 years of age, consider IIV or RIV at least 1 month after transplantation. For SOT recipients 18 years and older receiving immunosuppressive medications, HD or aIIV are acceptable options.
Last reviewed:
October 11, 2026
