New flu Variant and Declining Vaccination Rates Raise Concerns for severe US Flu Season
ATLANTA – A newly circulating influenza subclade, dubbed K, coupled with a concerning drop in flu vaccination rates across the United States, is prompting health experts to warn of a possibly severe flu season. While the current flu shot offers protection, its effectiveness may be hampered by the variant’s emergence and reduced uptake of vaccination.
Early indicators suggest a rise in flu activity nationwide, with type A influenza detected in 40% of wastewater samples in November – a meaningful increase from 18% in October, according to data from the WastewaterSCAN network. This comes as vaccination numbers lag behind last year, with pharmacies administering 26.5 million flu shots from August thru October, down from 28.7 million during the same period in 2024, according to IQVIA data.
The emerging subclade K presents a challenge because it differs enough from previous strains that it may be less easily recognized by the existing immunity developed from prior infections or vaccinations. Despite this, the flu shot has demonstrated effectiveness, reducing the risk of hospitalization or emergency care by approximately 75% in children and 30% to 40% in adults so far this season.
“What they saw in Australia is that they had a bad season. And so it’s concerning for you and us,what’s coming,” warned Dr. earl Rubin,division director of infectious disease at Montreal Children’s Hospital,referencing Australia’s experience this year with over 443,000 flu cases following a decline in vaccination rates.
Experts also point to growing vaccine hesitancy as a contributing factor.Jennifer Nuzzo, professor of epidemiology and director of the Pandemic Center at Brown university, noted that recent debates about vaccine safety have “left people confused but possibly at the worst have left people worried about getting vaccinated.”
Currently, only four U.S. monitoring sites – in Maine, vermont, Iowa, and Hawaii – have officially reported high flu activity. Though, Marlene Wolfe, an assistant professor at Emory University, emphasizes that the upward trend is undeniable.
“It’s not too late. Go and get your flu shot,” urged Dr. Adam Lauring, chief of the division of infectious diseases at the University of Michigan Medical School.
These preliminary findings have not yet undergone peer review. More information on the flu vaccine is available from the Texas Department of State Health Services (DSHS).