Author: Siddhi Mahatole and Sriparna Roy
Dec 31 (Reuters) – Flu cases are rising across the United States amid holiday travel and gatherings, with infections rising faster than in previous years, according to the latest data from the U.S. Centers for Disease Control and Prevention.
Estimates released Tuesday showed at least 7.5 million people have become sick, 81,000 hospitalized and 3,100 have died so far this quarter, and experts warn that the numbers are likely to continue to rise.
Public health experts told Reuters holiday travel, low vaccination rates and misinformation were to blame for the surge in cases.
Of the 275 viruses collected since September 28, 2025 that underwent additional genetic characterization at CDC, 89.5% belonged to subclade K, a variant of influenza A H3N2 virus.
Andrew Pekosz, a virologist at the Johns Hopkins Bloomberg School of Public Health, said an important factor in this year’s flu season will be how quickly cases occur once the flu virus enters a state or geographic area.
He said some experimental data and genetic sequences also showed that the virus seemed to have some mutations that would avoid some herd immunity.
According to the Centers for Disease Control and Prevention (CDC), more than 19,000 flu patients were hospitalized in the week ending December 20, an increase of about 10,000 from the previous week.
Five flu-related pediatric deaths were reported last week, bringing the total for the 2025-26 season to eight.
“This could be a much more severe flu season than what we’ve seen in years past, but so far we have no evidence that it’s more severe in every patient,” said Daniel Kuritzkes, a senior infectious disease physician at Massachusetts General Hospital Brigham General.
The CDC reports that while severity indicators remain low, flu activity is expected to continue for several weeks.
The agency urges anyone six months and older who has not yet received a flu shot to get one.
Experts also say that while there is a mismatch between vaccines and virus strains, people should get vaccinated, which induces some antibodies that recognize the new variant and help fight the disease.
“We know the vaccine is not a perfect match for this strain… because there are some mutations that have occurred in the flu virus,” said Eric Asher, a family medicine physician at Lenox Hill Hospital in Northwell.
The CDC says about 130 million doses of flu vaccine have been distributed in the country this season.
“The mix of all the holidays is bound to increase transmission, but we haven’t seen the start of an accelerated decline in cases yet,” said Duke University professor Cameron Wolfe.
(Reporting by Siddhi Mahatole and Sriparna Roy in Bengaluru; Editing by Shilpi Majumdar)
