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Moderna mRNA flu vaccine mFlusiva US launch and scrutiny

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2026-09-25 10:53 UTC → 2026-09-30 03:14 UTC · added ~~removed~~

By late September 2026, Moderna’s mFlusiva has become available at over 13,000 locations across the United States, including pharmacies such as CVS and Walgreens. The mRNA-based vaccine, which provides genetic instructions to trigger an immune response rather than using inactivated virus particles, offers a faster production timeline of two to three months compared to the six months required for conventional formulas. While clinical trials suggest the formulation may offer superior protection against certain influenza A strains, data also indicates a higher frequency of mild-to-moderate systemic side effects, such as fever, fatigue, and muscle aches. No increase in serious adverse events has been reported in these findings. However, the vaccine has not yet been tested in immunocompromised populations. The rollout continues to face scrutiny following a reanalysis of FDA clinical data published on the preprint server Zenodo. Researchers, including Dr. Peter McCullough and Nicolas Hulscher, have called for the vaccine's withdrawal, claiming it shows ‘abysmal efficacy’ in preventing hospitalizations and carries a higher risk of adverse events, including death, compared to non-mRNA standard-dose vaccines. They have urged Health and Human Services Secretary Robert F. Kennedy Jr. to halt distribution. In Washington, availability of the vaccine varies as it is only included in some Medicare plans, with an estimated cost of approximately $171 for those without insurance. While some reports indicate the FDA has approved mFlusiva for adults aged 50 and older, other regional guidance recommends it specifically for individuals aged 65 and older, noting that approval for the 50 to 64 age range may still be pending in certain contexts.

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