Houston's flu cases are rising

Flu cases are spiking in Houston just as people are headed 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: Houston Health Department is reporting the city ended 2025 with high levels of people with the flu visiting the doctor.

• City data shows 52% of those infected are 5 to 17 years old and 24% are under 5.
• There are also high levels of the flu detected in wastewater, and the number is increasing, per the department.

Zoom out: Houston's surge mirrors what's happening across Texas, where flu activity has reached very high levels and more than 4 in 10 hospital flu tests are coming back positive.

• Cases of the flu remain elevated nationwide, according to data from the CDC, which shows there's 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 an example of the "super flu," referring to a strain that spreads quickly and rapidly, becoming more troublesome.

Reality check: 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 more severe than usual strain of the flu circulating, experts say.

The bottom line: Andrew Pekosz, a virologist at Johns Hopkins University, recommends getting a flu shot for those who haven't.