Flu season is declining but remains severe

CDC data show flu cases and wastewater signals are falling in early January after a record-high December, but the season has caused roughly 180,000 hospitalizations and 7,400 deaths and remains driven largely by an H3N2 subclade called K.

Flu activity in the United States has eased in early January after a sharp rise through December. The Centers for Disease Control and Prevention reported historically high flu-related medical visits at the end of December and says activity remains elevated. The season has produced substantial hospitalizations and deaths, and public health agencies note a mutated H3N2 variant, called subclade K, is now widespread. Officials have said elevated influenza activity is expected to continue for several more weeks. Key facts: - CDC tracking showed test positivity fell to about 25% for the week ending Jan. 3, down from about 32% the prior week. - The agency reports about 180,000 hospitalizations and roughly 7,400 deaths this season, with 17 known pediatric deaths reported. - Genetic surveillance found H3N2 accounted for over 92% of tested influenza A cases that week, and about 91.5% of those H3N2 viruses were subclade K. - WasteWaterSCAN reported a 37% drop in median flu signal between Dec. 26 and Jan. 7, and CDC projections on Jan. 6 showed cases declining or likely declining in 44 states. Summary: Detected flu circulation has begun to fall in early January, but the overall health impact this season remains substantial. The CDC and other agencies report that elevated activity is likely to persist for several more weeks. Undetermined at this time.