Overview
- CDC estimates at least 7.5 million illnesses, 81,000 hospitalizations and 3,100 deaths so far this season, including eight pediatric deaths, based on data through Dec. 20.
- Hospital admissions with confirmed flu jumped 91% in the week ending Dec. 20 to about 19,000, and most states now report high or very high activity.
- New York recorded roughly 71,000 cases in the Dec. 20 week, its highest weekly total since tracking began in 2004, as emergency visits rose sharply in multiple regions.
- Genetic testing shows a drifted H3N2 offshoot known as subclade K is driving the vast majority of U.S. cases, reducing protection against infection but not eliminating vaccine benefits against severe disease.
- Vaccine uptake is lagging last year with about 130 million doses distributed, and health officials continue to urge vaccination, early antiviral treatment for high‑risk patients and basic precautions.