The defense secretary broke with public health directives when he made the flu vaccine optional for all U.S. military personnel, both active and reserve, in April.

A summer influenza outbreak didn't break epidemiology, it affirmed everything we know

As of June 19, around 222 flu cases were reported on Lackland Air Force Base in San Antonio, Texas

Hegseth had announced a vaccine rollback in April and described the mandate as an issue of "medical autonomy" and religious freedom.