The most recent COVID-19 vaccines in the United States follow a 2025-2026 formula, recommended by the CDC for everyone ages 6 months and older. The previous update, the 2024-2025 formula approved in August 2024, targeted the Omicron KP.2 subvariant and was available from Pfizer, Moderna, and Novavax. COVID vaccines are now updated on a roughly annual schedule, similar to the flu shot, to keep pace with circulating variants.
What the 2024-2025 Formula Targeted
The FDA approved updated mRNA vaccines from both Pfizer (Comirnaty) and Moderna (Spikevax) on August 22, 2024. These shots used a single-component design targeting the KP.2 strain, a descendant of the Omicron JN.1 lineage. During the months that followed, the dominant circulating variants were KP.2, KP.3, and a newer variant called XEC. Because XEC is closely related to KP.2 and JN.1, the vaccines maintained relevant protection even as the virus continued to evolve.
Novavax, which uses a protein-based approach rather than mRNA technology, also offered an updated formula for the 2024-2025 season. In August 2025, the FDA granted full approval to the Novavax vaccine (now branded as Nuvaxovid), giving people who prefer a non-mRNA option continued access.
How Well the Updated Vaccines Work
Real-world effectiveness data from two CDC surveillance networks, covering September 2024 through January 2025, showed moderate but meaningful protection. Among adults 18 and older, the updated vaccine reduced COVID-related emergency department and urgent care visits by 33%. For adults 65 and older with healthy immune systems, protection against hospitalization was stronger: 45% to 46% in the first four months after vaccination.
Older adults with weakened immune systems also benefited, though slightly less. Their protection against hospitalization was about 40% during the same window. These numbers reflect real-world conditions where the virus was actively shifting between subvariants, so they represent a practical floor rather than a ceiling.
For context, these effectiveness levels are comparable to what flu vaccines deliver in a typical season. The protection is not a guarantee against infection, but it substantially lowers your odds of ending up in a hospital bed.
Who Should Get It
The CDC recommends the current COVID vaccine for anyone 6 months and older, with the decision framed as an individual choice. That said, vaccination is especially important for certain groups:
- Adults 65 and older, who face the highest hospitalization and death rates from COVID
- People at high risk for severe illness, including those with heart disease, diabetes, obesity, or lung conditions
- People who are pregnant or planning to become pregnant
- Residents of long-term care facilities
- Anyone who has never received a COVID vaccine
- People who want to reduce their risk of Long COVID
If you are moderately or severely immunocompromised, the CDC has separate guidance that may include additional doses beyond what’s recommended for the general population.
Protection Against Long COVID
Beyond preventing severe acute illness, vaccination appears to reduce the risk of developing Long COVID. A literature review by the European Centre for Disease Prevention and Control found that fully vaccinated adults had roughly a 27% lower risk of Long COVID compared to unvaccinated individuals. Six out of seven high-quality studies included in that review showed a statistically significant reduction. This is one of the few tools available for lowering Long COVID risk, which makes it relevant even for younger, healthier people who might not worry much about hospitalization.
Side Effects to Expect
The side effect profile of the updated vaccines is consistent with earlier versions. The most common reactions are soreness at the injection site, fatigue, headache, muscle aches, chills, and occasionally fever. Most symptoms are mild to moderate, start within one to three days of the shot, and clear up within one to three days. Younger people tend to report more noticeable systemic reactions like fatigue and body aches, while injection-site pain is common across all ages.
Myocarditis and pericarditis (inflammation of the heart or its lining) remain rare but documented risks, occurring most often in adolescent and young adult males, typically within a week of the second dose. This risk has also been observed, though less frequently, with the Novavax vaccine. For young children receiving a multi-dose initial series, spacing doses eight weeks apart may further reduce this already small risk.
Timing After a Recent Infection
If you recently tested positive for COVID, you can delay your vaccine by three months from the date your symptoms started, or from the date of your positive test if you had no symptoms. You still need the vaccine eventually, since natural immunity wanes over time just as vaccine immunity does. But waiting three months lets your body’s natural immune response do its work before adding the boost from vaccination, potentially giving you a longer overall window of protection.
Cost and Access
Most people with health insurance, including Medicare and Medicaid, can get the COVID vaccine at no out-of-pocket cost. If you’re uninsured, the picture is more complicated since the federal Bridge Access Program ended in 2024. Local immunization programs run by health departments or community organizations may still offer low-cost or free vaccines in your area. HRSA-supported health centers are another option for uninsured individuals seeking affordable access to COVID-related care, including vaccination.