The mRNA Flu Shot Isn't Killing a Quarter of Its Recipients

On September 17, @CHANNAKAJIMA warned followers off this year's flu shot: "75% survival rate - 25% death and injury. It is that mRNA poison they shoved into people for covid-19." The post quoted a bigger one from @toobaffled, seen about 51,000 times, calling the COVID and flu shots "the same product line," like they come in a combo pack.

One piece is real. On August 5, the FDA licensed Moderna's mFLUSIVA, an mRNA flu vaccine for adults 50 and older. It isn't "the flu shot this year." CDC's table for the season lists eight vaccines, none of them mRNA, and the CDC's vaccine advisers haven't voted on mFLUSIVA at all. Your pharmacy is serving the same shots as last year.

The 25% comes from nowhere. In the trial behind the license, about 40,700 adults got either mFLUSIVA or a standard shot. Serious medical events of any cause showed up in 2.2% of the mFLUSIVA group and 1.9% of the comparison group over six months, about normal for older adults over half a year. Investigators tied one case to the vaccine: a fainting spell with fever. A 25% rate would have meant about 5,000 casualties among the 20,350 people who got the shot, and nobody needs years of follow-up to spot a few hospital wings filling up. Problems that hit a few people per million doses take millions of doses to surface, and mFLUSIVA isn't close.

Run the post's math on the 147.55 million flu doses handed out last season and you get nearly 37 million Americans dead or injured in one fall. Influenza itself kills between 6,300 and 52,000 a year.

Whether mFLUSIVA keeps people 65 and older from getting sick is a fair question, and Moderna still owes us the answer. @CHANNAKAJIMA skipped this for a made-up number.

Verdict: 4 Dangerous. False, and with real potential for harm: a made-up casualty rate could scare people away from a safe, routine flu shot.

Sources: FDA on mFLUSIVA · CDC 2026–27 flu vaccines