Flu Infections Surge Amid Holiday Season, Raising Concerns Among Health Officials

Wed Jan 07 2026 12:33:56 GMT+0200 (Eastern European Standard Time)

With U.S. flu infections spiking over the holidays, health officials warn of a potentially severe season, driven by a new variant strain of flu that may complicate vaccination efforts.

The holiday period has seen a dramatic rise in flu infections across the U.S., prompting health officials to label the current flu season as severe. Despite rising COVID-19 cases, flu remains the more pressing concern, particularly due to the prevalence of the H3N2 variant, which has raised fears about the effectiveness of the vaccine this year. Early data suggest this season is already outpacing the severe flu season experienced last winter, and health experts advise vaccinations as a precaution as flu activity is unlikely to peak until later in the winter.

NEW YORK (AP) — U.S. flu infections surged over the holidays, with health officials labeling the current season as potentially severe and likely to worsen.

Data from the Centers for Disease Control and Prevention (CDC) indicates that flu activity during the week of Christmas has already outstripped last winter's severe flu epidemic by some measures.

Moreover, COVID-19 infections have been on the rise, although they remain less prevalent than flu cases, according to federal health data.

Reports indicate that 45 states are observing high or very high flu activity, a steep increase from 30 states the prior week.

Public health experts attribute this surge partly to the dominance of the H3N2 strain of the flu virus, historically associated with more severe cases among older populations. Alarmingly, over 90% of the H3N2 cases analyzed were of the new subclade K variant, which does not match the strain included in this season's flu vaccine.

Since peak flu seasons often occur in January or February, it remains uncertain how significant the effects of this vaccine mismatch will ultimately be.

Last flu season saw the highest hospitalization rates since the H1N1 pandemic, with 288 flu-related child deaths reported—an unprecedented figure for the typical flu season in the U.S.

So far this season, nine pediatric flu deaths have been documented, with emergency department visits for flu-like symptoms exceeding previous high levels during last season.

The CDC estimates a total of at least 11 million flu illnesses, 120,000 hospitalizations, and 5,000 deaths already this season. Health authorities recommend that everyone aged six months or older who has not yet been vaccinated this season receive an annual flu vaccine.