The U.S. flu season is concluding with a significantly low vaccine effectiveness rate of 25% to 30% for adults, primarily due to a mismatch between the vaccine and a dominant new H3N2 strain called subclade K. Despite at least 22,000 deaths and 27 million illnesses this season, health officials emphasize that vaccination remains crucial as it significantly reduces the risk of severe disease and death. Current CDC data shows a slight increase in adult vaccination rates but a decline in childhood immunizations following a shift in federal policy that removed broad flu shot recommendations for minors. Looking ahead, the World Health Organization and the FDA have already endorsed updated vaccine formulas for the 2026-27 season specifically designed to target the subclade K mutation.
Date: March 13, 2026. Source: apnews.com