Flu Vaccination Decline Raises Fears of a Deadlier US Winter

Americans are heading into winter less protected against one of the season’s deadliest viruses, with flu vaccination rates forecast to fall more than 10% this year, according to CSL Ltd., the world’s second-biggest maker of the shots.

CSL expects US vaccination rates for the 2025-2026 season to drop 12% overall and 14% among people ages 65 and older compared with last year, Chief Executive Officer Paul McKenzie told the company’s annual meeting in Melbourne on Tuesday, citing insurance-claims data.

The downturn in flu vaccination observed by CSL provides a now-rare glimpse into Americans’ uptake of the shots since the ...