SAN ANTONIO — The Pentagon now requires flu vaccinations for all recruits in military boot camps, reversing a policy from late April 2026 that made them optional. The change follows a flu outbreak at the U.S. Air Force boot camp at Lackland Air Force Base that sickened hundreds.

Defense Secretary Pete Hegseth had made flu vaccinations optional for the military in late April 2026. Hegseth cited "medical autonomy" and religious freedom when he announced the repeal of the flu vaccine mandate. He also stated that flu shot requirements were "not rational" and that removing the requirement was "restoring freedom" to military members.

During the interim period, Hegseth allowed military services to request exceptions to keep the flu vaccine mandatory within 15 days of the rollout of the optional policy. Sean Parnell, the Pentagon's top spokesman, confirmed that exceptions were granted to the Army, Navy, Air Force, National Security Agency, and Defense Health Agency. Army and Navy officials had requested permission to make flu shots mandatory for troops deploying overseas, as well as for healthcare workers and child care workers.

A Pentagon official said that decisions on these exceptions were being finalized in early June 2026. The official also stated on June 24, 2026, that the new requirement to mandate flu vaccinations was unrelated to the outbreak at Lackland Air Force Base. At Lackland, roughly 700 new recruits arrive every week.

The flu outbreak at Lackland Air Force Base sickened at least 222 recruits and hospitalized four. A source familiar with the situation indicated that 40% of new trainees at Lackland opted to receive the flu shot when it became optional. Recruit Keon McDaniel died on June 12, 2026, after suffering a medical emergency during his sixth week of basic training at the base.

Dr. Arnold Monto, an Emeritus Professor at the University of Michigan, stated, "If you want to prevent flu outbreaks, it is especially necessary to vaccinate when there are group settings." Monto also stated, "The new outbreak is not unusually concerning."

Michele Slafkosky, Executive Director of Families Fighting Flu, addressed the previous policy. "For decades, the military prioritized the health and safety of troops and the public by requiring flu vaccine for recruits. It's unfortunate that more than 200 individuals at Lackland Air Force Base in Texas became ill when that requirement was rescinded." Regarding the updated guidance, Slafkosky stated, "This updated guidance from the military will save lives."