RFK, Jr.–Backed Lyme Disease Conspiracy Theory May Be Probed under New Bill

President Donald Trump is expected to sign a defense bill this week that orders an investigation into whether the U.S. military bioengineered Lyme disease

By Claire Cameron edited by Andrea Thompson

Infected female deer tick on hairy human skin — Oleg Marchak via Getty Images

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U.S. president Donald Trump is expected to sign a defense bill this week that orders a government watchdog to probe a conspiracy theory—promoted by the country’s secretary of health and human services Robert F. Kennedy, Jr. —that the U.S. military bioengineered Lyme disease.

Bacteria, usually Borrelia burgdorferi, carried by black-legged ticks, also known as deer ticks, causes Lyme disease. The bacteria originate in rodents—ticks bite the animals and become carriers, and then the arachnids bite humans, sometimes passing the bacteria on. Ticks typically need to be attached to someone for a day or longer to actually spread the bacteria to their host, however.

Despite this established pathway for the disease, Kennedy has promoted the conspiracy theory that Lyme was bioengineered; on a 2024 podcast, he mused that the condition “is highly likely to have been a military weapon.” And at a roundtable on Monday, Kennedy appeared alongside Republican Representative Chris Smith of New Jersey, who authored the defense bill directive to investigate a possible connection between the military and Lyme.

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If the bill passes into law as currently written, the Government Accountability Office will be ordered to investigate a link, E&E News’ Climatewire reported. “GAO will be fully empowered to leave no stone unturned, and now it’ll have a congressional mandate to get to the bottom of it because they were weaponizing ticks,” Smith said at the Monday roundtable.

Lyme disease cases have skyrocketed in recent years, according to the Centers for Disease Control and Prevention, with estimated diagnoses now numbering around nearly half a million people each year. Experts believe climate change, more accurate reporting and land use are likely pushing the numbers up.

The Department of Health and Human Services did not immediately respond to a request for comment.

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