• Posted January 2, 2026

Holiday Flu Surge Drives Record Illness Across the U.S. — Here's What You Can Do

The holiday season brought a massive spike in influenza cases across the U.S. 

New data from the U.S. Centers for Disease Control and Prevention (CDC) indicates that the virus is spreading rapidly, with some regions reporting record numbers of infections and hospitalizations.

At least 7.5 million people had been sickened by late December, resulting in at least 81,000 hospitalizations and 3,100 deaths, including eight pediatric deaths.

The geographical spread is widening quickly: 32 jurisdictions report "high" or "very high" levels of flu-like activity, nearly double the number from a week before.

New York and Massachusetts are among the hardest-hit areas. The New York State Department of Health reported about 71,000 cases in the week ending Dec. 20 — the highest weekly total since the start of its current tracking system in 2004. Meanwhile, Boston has seen a 114% increase in cases, with kids accounting for the largest share of the new infections.

In Minnesota, a significant spike in illness forced at least one school to transition to remote learning just before the winter break.

Health experts are particularly concerned about the dominance of a specific Influenza A subtype known as H3N2. It accounted for nearly 92% of all flu samples recently analyzed by the CDC.

H3N2 is notorious for causing more severe flu seasons, especially for older adults. 

"The virus has changed just enough to make it harder for people's immune systems to recognize the illness," said Jesse Bloom, a scientist at the Fred Hutchinson Cancer Center in Seattle.

He told CBS News that this shift allows the virus to bypass some of the defenses the body has built up from previous infections.

While there are concerns that this year's vaccine might not perfectly match the circulating H3N2 strain, experts emphasize that the shot remains a vital tool.

Data from the United Kingdom suggests that even with the "mismatch," the vaccine is still highly effective at helping people stay out of the hospital with severe infection, especially children.

Unfortunately, vaccine uptake is lower this year, with only about 130 million doses administered so far in the U.S., reports CBS News. Health officials urge those who have not yet been vaccinated to get the shot immediately. 

"It's not going to eliminate their chance of getting infected," Bloom said, "But it does mitigate their risk."

Getting the flu vaccine, staying away from those who are sick, washing hands often and disinfecting surfaces are key ways to prevent illness, according to the CDC.

More information 

The latest prevention tips, vaccine information and treatment options for the flu are outlined at the U.S. Centers for Disease Control and Prevention.

SOURCE: CBS News, Dec. 30, 2025