Despite fears that Robert F. Kennedy Jr.'s tenure as US health secretary would disrupt this year's flu and COVID-19 vaccine rollout, the season is shaping up to be largely routine. The CDC's vaccine advisory committee remains defunct after a federal judge ruled in March that Kennedy's appointees were illegally installed, voiding their policy changes, but the FDA has approved updated flu and COVID shots, which are already reaching pharmacies, and major insurers have agreed to keep covering recommended vaccines free of charge until at least the end of 2027.

With the official advisory process sidelined, a coalition of medical bodies including the American Medical Association, the American Academy of Pediatrics and the Infectious Diseases Society of America published their own evidence-based recommendations for 2026-27, largely unchanged from last year. Trivalent flu vaccines are advised for everyone aged six months and up, with a nasal-spray option for ages two to 49 (excluding pregnant or immunocompromised people) and a high-dose version for over-65s. The main new development is Moderna's mRNA flu vaccine, mFlusiva, approved in August for adults 50 and over, which trials found 27 percent more effective than standard shots but with somewhat more frequent mild side effects such as fatigue and soreness at the injection site.