Flu activity is running ahead of its usual early-October pace this year, federal surveillance data show, even as health officials say levels remain within the range of normal seasonal variation. The CDC's most recent FluView report, covering the week ending October 3, found clinical laboratories reporting 3.6% of specimens positive for influenza, with the West Coast — HHS Regions 9 and 10 — showing the highest activity in the country.
Nearly all of this season's flu so far is one strain: of the influenza A viruses subtyped by public health labs in that week, 98.4% were A(H1N1)pdm09 and just 1.6% were A(H3N2). Hospitalization rates are still low in absolute terms — about 1.0 per 100,000 people nationally, per the CDC's NHSN hospital-reporting network — but have been climbing since August, and adults 65 and older have the highest rate of any age group, at 3.3 per 100,000. The CDC's own language is measured: this season's early activity is "higher than typically observed at this time of year but remains within expected seasonal variation," the agency said, stopping short of calling it an early or severe season.
A new vaccine option reaches pharmacies
This is the first flu season in which Americans can get a messenger-RNA-based flu shot. The FDA approved Moderna's mFlusiva (mRNA-1010) in early August for adults, full approval for ages 50 to 64 and accelerated approval for those 65 and older pending further study, after a roughly 40,000-person trial found about 27% fewer flu cases among recipients compared with a standard flu vaccine, according to reporting distributed by the Associated Press. Moderna said it expected supply to begin reaching select retailers this season; it is not a replacement for existing flu shots, which remain the primary recommended option, and most people will likely still receive one of the established egg- or cell-based vaccines.
Complicating the backdrop, the CDC's Advisory Committee on Immunization Practices — the body that typically issues detailed, consensus federal vaccine recommendations — has been described by some state health departments as inactive this year, prompting a handful of states to lean more heavily on guidance from medical societies such as the American Academy of Pediatrics. The CDC's interim guidance for 2026-2027 carries over the prior season's core recommendations: annual vaccination for everyone six months and older, ideally completed before the end of October, with people 65 and older preferentially offered a high-dose, recombinant or adjuvanted vaccine.
One methodological note on the surveillance numbers themselves: early-October positivity rates are based on a relatively small share of specimens tested so far this season, and CDC's early-season figures can shift as more labs report and as the mix of circulating strains evolves — a pattern seen in past years when an early H1N1-dominant start gave way to co-circulation with H3N2 later in the winter.
What happens next: CDC's weekly FluView updates will show whether the current H1N1-dominant, West Coast-centered pattern spreads nationally in the coming weeks, which is typically the clearest early signal of how severe a given flu season will be.
