WASHINGTON — The Department of Defense announced Wednesday that all military branch boot camps will once again require flu vaccinations for incoming recruits, reversing a policy change made just weeks ago by Defense Secretary Pete Hegseth.
Hegseth had made the flu shot optional across the military at the end of April, citing “medical autonomy” and religious freedom. At that time, however, he left the door open for individual branches to request exceptions — meaning they could apply to keep the vaccination mandatory — within 15 days of the policy taking effect.
A Pentagon official confirmed the change to the Associated Press, speaking on the condition of anonymity because the details had not been cleared for public release. The official said the decisions on those exception requests were being wrapped up in early June, and insisted the timing had nothing to do with a flu outbreak currently spreading through the U.S. Air Force’s boot camp at Lackland Air Force Base.
That outbreak has now stretched to roughly three weeks. Democratic Rep. Joaquin Castro, whose district includes part of the base, announced on social media that 275 confirmed flu cases have been recorded there. The base processes approximately 700 new recruits each week, according to Air Force data.
A source familiar with the situation told the AP that once the flu shot became optional, only 40% of new trainees at Lackland chose to receive it. That source also spoke anonymously because the information was not approved for public release.
Experts say the environment at military boot camps is particularly vulnerable to the spread of illness. Recruits live under high stress, get limited sleep, and spend extended periods in close contact with one another. They typically sleep in large open bays, share communal showers, and receive instruction in tight group settings — all conditions that make it easy for viruses to spread.
Dr. Arnold Monto, a flu expert and emeritus professor at the University of Michigan, said the Lackland outbreak is “not unusually concerning.” He noted that while flu is most common in the fall and winter months, the virus does circulate at lower levels year-round. Outbreaks in spring and summer tend to occur in places where large groups of people gather indoors, such as military bases and cruise ships.
“It is especially necessary to vaccinate when there are group settings,” Monto said.
Pentagon spokesman Sean Parnell confirmed in a statement that exceptions were granted to the Army, Navy, and Air Force, as well as the National Security Agency and the Defense Health Agency, though he declined to provide additional details. Army and Navy officials have separately indicated they also requested permission to mandate the vaccine for broader groups, including troops deploying overseas, healthcare workers, and childcare workers.
Advocacy group Families Fighting Flu welcomed the move. Executive Director Michele Slafkosky said in a statement: “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.”
“This updated guidance from the military will save lives,” Slafkosky added.
