Bexar County's flu positivity more than quadrupled in December
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Flu cases are spiking in Bexar County, just as people head back to work and school.
The big picture: An unprecedented rise in flu cases comes as other sicknesses — such as the "winter vomiting bug," COVID and whooping cough — are slamming the U.S. this winter.
Zoom in: Flu test positivity more than quadrupled from early to late December in Bexar County, according to Metro Health.
- Roughly 11% of all emergency department visits were flu-related in the week ending on Dec. 27, compared to just shy of 6% at the same point in 2024, per Metro Health.
Zoom out: San Antonio's surge mirrors what's happening across Texas — flu activity reached very high levels at the end of 2025, and more than 40% of hospital flu tests were positive statewide.
Reality check: Flu surveillance relies on testing and health care visits, so it does not capture people who manage illness at home.
The big picture: Cases of the flu remain elevated nationwide, according to CDC data, which shows there have been at least 11 million illnesses, 120,000 hospitalizations and 5,000 deaths from the flu so far this season.
- Many of these cases have been tied to "subclade K" — a variant of the H3N2 virus, which is a subtype of influenza A.
Experts and patients say subclade K is similar to a "super flu," referring to a strain that spreads quickly and rapidly, becoming more troublesome.
Yes, but: Although subclade K is being associated with the term, there isn't an official "super flu."
- The term emerges every so often, typically when there's a strain circulating that's more severe than usual, experts say.
The bottom line: It's not too late to get your vaccine. Metro Health tells Axios it's "too early to tell" when our flu season will peak.
- "In previous seasons, we have seen the influenza season peak in late January to early February," the department said in an email.