The vaccines are FDA-licensed for use in adults ≥65 years old and in persons aged 6 months-64 years (Spikevax), 5-64 years (Comirnaty), or 12-64 years (mNEXSPIKE, Nuvaxovid) who are at high risk for severe COVID-19 because of an underlying condition.

THE NEW FORMULAS — The 2026-2027 COVID-19 vaccines are monovalent. They target the spike protein of the XFG Omicron strain of SARS-CoV-2, which is descended from the JN.1 strain and is currently the dominant circulating strain in the US.2 Comirnaty and Spikevax code for the entire spike protein; mNEXSPIKE codes only for the N-terminal and receptor-binding domains of the spike protein. Nuvaxovid contains a recombinant form of the spike protein.

DOSAGE AND ADMINISTRATION — For most patients, a single dose of a 2026-2027 COVID-19 vaccine administered ≥2 months after any previous COVID-19 vaccine dose is recommended. Additional doses are recommended for immunocompromised patients,3,4 children 6-23 months old who have never been vaccinated against COVID-19, and adults ≥65 years old (see Table 1).

RECOMMENDATIONS — The risk of severe outcomes from COVID-19 is highest in older adults, persons with underlying medical conditions, and residents of long-term care facilities (see Table 2). The CDC recommends COVID-19 vaccination for all persons ≥18 years old and for children 6 months-17 years old with moderate to severe immunocompromise; they say the decision to vaccinate other children should be based on shared clinical decision-making.5 Four medical societies have provided 2026-2027 vaccination recommendations for specific patient populations according to their individual areas of specialization (see Table 3); the recommendations are intended to be combined to provide guidance for all US residents.4,6-8

EFFECTIVENESS — Licensure of the 2026-2027 vaccines was based on the immunogenicity, safety, and effectiveness of previous vaccines. In previous seasons, COVID-19 vaccination has been associated with reductions in the risk of severe disease, emergency department visits, hospitalizations, and deaths in children, adults, and persons with immunocompromising conditions.9-12

ADVERSE EFFECTS — Adverse effects of currently licensed US COVID-19 vaccines have included injection-site reactions, fatigue, fever, chills, muscle and joint pain, headache, nausea, vomiting, and lymphadenopathy. Vaccine-related serious adverse events have been rare. Severe allergic reactions have occurred.

Myocarditis and pericarditis have occurred rarely following COVID-19 vaccination; the incidence has been highest in adolescent and young adult males.13 Myocarditis and pericarditis can also occur with SARS-CoV-2 infection.14

PREGNANCY AND LACTATION — SARS-CoV-2 infection has been associated with an increased risk of adverse pregnancy outcomes. In a retrospective cohort study of in-hospital deliveries, pregnant women infected with SARS-CoV-2 had higher rates of severe morbidity, ICU admission, and in-hospital mortality; increased risks of preterm birth, cesarean delivery, and fetal death at ≥20 weeks' gestation were also observed.15

COVID-19 vaccination has been shown to protect pregnant women against adverse outcomes while providing passive immunity to their infants.16-20 Administration of COVID-19 vaccines to breastfeeding women is considered safe.6

The American College of Obstetricians and Gynecologists (ACOG) recommends COVID-19 vaccination for women who are pregnant (any trimester), recently pregnant, contemplating pregnancy, or breastfeeding.6

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