Flu outbreak sickens Lackland trainees after vaccine mandate ends

A flu outbreak has sickened scores of Air Force trainees at Lackland Air Force Base in San Antonio, weeks after Defense Secretary Pete Hegseth ended the military’s long-standing requirement for annual influenza vaccination.

“Over the last three weeks, the 37th Training Wing, in close coordination with the 59th Medical Wing, has been managing a localized influenza outbreak among trainees at Basic Military Training,” an Air Force spokesperson told CBS News.

At least 159 recruits have fallen ill, The New York Times and ABC News reported, according to The Guardian. CBS News reported that dozens of service members at the Texas base have contracted the flu, citing sources familiar with the situation.

The 37th Training Wing has begun isolating and treating trainees with symptoms and monitoring others who may have been exposed, according to the Air Force statement reported by CBS News. Symptomatic trainees are receiving antiviral medications such as Tamiflu.

The outbreak follows Hegseth’s April memo rescinding the decades-old military flu vaccine mandate. In an accompanying social media video, Hegseth said the Pentagon was “seizing this moment to discard any absurd, overreaching mandates that only weaken our warfighting capability.”

The Guardian reported that Hegseth also said, “In this case that includes the universal flu vaccine and the mandate behind it,” adding, “Your body, your faith and your convictions are not negotiable.”

Since the mandate was lifted, only about 40% of Air Force trainees have chosen to receive the flu vaccine, sources familiar with the matter confirmed to CBS News. The New York Times reported the same figure based on Air Force officials, according to The Guardian. By comparison, about 46% of adults were vaccinated against influenza in the 2025-26 cold season, according to the Centers for Disease Control and Prevention, The Guardian reported.

The Pentagon said Thursday that the new policy still allows exceptions when military departments or defense agencies determine vaccination is needed. Chief Pentagon spokesman Sean Parnell said the Under Secretary of Defense for Personnel and Readiness granted exceptions to the policy for the Army, Navy, Air Force, National Security Agency and Defense Health Agency if there were needs to make the vaccine mandatory.

“The decisions were based upon thorough risk assessments and are designed to maximize operational readiness, lethality, and force generation, while safeguarding at-risk populations,” Parnell said. “The Army, Navy, Air Force, NSA, and DHA are responsible for implementing the ETPs,” he added, referring to exceptions to policy. “The Department remains committed to the health and readiness of our warfighters and civilian personnel.”

Air Force officials said recruits at Lackland had been ordered to receive flu vaccinations as part of containment efforts, The New York Times reported, according to The Guardian.

Lackland is part of Joint Base San Antonio, a 70,000-member installation sometimes called Military City, The Guardian reported. Recruits there live in communal settings, including dormitories, and eat together. The 37th Training Wing is the Air Force’s largest training wing and provides basic military training for all enlisted recruits entering the Air Force, Space Force, Air Force Reserve and Air National Guard, according to an Air Force fact sheet cited by CBS News.

The Air Force also announced that trainee Keon McDaniel, who was in his sixth week of basic military training, died June 16 at Brooke Army Medical Center after a medical emergency. He had been taken there June 12 for care. The cause of the emergency remains under investigation, and it is not clear whether his death was related to the flu outbreak.