A flu outbreak has torn through the basic training wing at Lackland Air Force Base in San Antonio, sickening more than 220 recruits and raising hard questions about War Secretary Pete Hegseth’s decision, less than two months earlier, to drop the requirement that all troops get a flu shot.

The outbreak hit the 37th Training Wing, the Air Force’s largest, which runs basic training for every enlisted recruit entering the Air Force, Space Force, Air Force Reserve, and Air National Guard. The wing, working with the 59th Medical Wing, has spent three weeks managing the outbreak, according to the Air Force. The setting made spread almost inevitable: Recruits sleep on bunk beds in open bays and eat at communal tables, the kind of close-quarters living that has fueled respiratory disease outbreaks among military personnel for centuries.