Hegseth says U.S. military no longer requires flu vaccination, drawing criticism from health experts

Hegseth says US military no longer requires flu vaccination, drawing criticism from health experts

By Jackie Flynn Mogensen edited by Claire Cameron

Updated April 21, 2026 has 5:15 p.m.

The U.S. military will no longer require its service members to be vaccinated against the flu, Defense Secretary Pete Hegseth said in a social media post Tuesday, a move that some health experts say could put troops at risk.

“The War Department is once again restoring freedom to our Joint Force. We are dropping the mandatory flu vaccine requirement, effective immediately,” Hegseth wrote in his message.

This policy contrasts with current recommendations from the U.S. Centers for Disease Control and Prevention (CDC), the nation’s top public health agency, which states that all Americans over six months of age who do not have contraindications should get a flu vaccine annually. The CDC estimates the vaccine saved some 12,000 lives and prevented about 180,000 hospitalizations during the 2024-2025 flu season.

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“Flu vaccines are the best tools we have to protect people from serious illness,” says Jennifer Nuzzo, a professor of epidemiology at Brown University. The vaccine doesn’t always prevent the flu, but it is effective in reducing the risk of hospitalization and serious illness, she explains.

It’s also a matter of national security, experts say. “I don’t understand why you would make this decision if troop readiness was important,” says Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota. The data on the flu vaccine is “clear and compelling” in terms of safety and the vaccine’s ability to reduce hospitalizations and deaths from severe illness, he says. “The data has been repeatedly confirmed to show this across all ages. »

“This is an irresponsible decision that will undermine the medical readiness of our troops,” said Georges Benjamin, CEO of the American Public Health Association. “[Hegseth] clearly demonstrates his inability to command the military forces of our country.

“In the military, vaccination is not political theater. It’s force protection. Troops live and work in close quarters, where the flu can spread quickly and sideline otherwise healthy service members,” Richard Ricciardi, a professor at the George Washington University School of Nursing who served in the US military for more than three decades, told CNN.

Notably, some of the first cases of influenza reported in the United States during the 1918 pandemic involved soldiers from Kansas who carried the virus with them to their camp, where it would then spread to the rest of the country and the rest of the world.

“If fewer service members were vaccinated against the flu, it would likely mean more troops would get sick during flu season, compromising the combat readiness of our armed forces and increasing health care costs paid by the U.S. government,” Nuzzo said. “With a growing number of global commitments, this seems like a particularly short-sighted policy.”

Editor’s Note (04/21/26): This is a breaking news story and will be updated.

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