A false rumor that the coronavirus outbreak is a plot by former Microsoft CEO Bill Gates is being spread by supporters of the pro-Trump QAnon movement and the anti-vax community.

A QAnon YouTuber named Jordan Sather warned his followers on Tuesday that the coronavirus was a “new fad disease” and claimed the release of the disease was “planned.” Following Sather’s heavily retweeted thread, the conspiracy theory traveled across Facebook, Twitter, and YouTube.

The newly discovered virus — a member of the coronavirus family that includes past outbreaks SARS and MERS — has infected more than 644 people and killed 18 since Dec. 31, 2019, according to Chinese news reports. Infected travelers have been detected in Japan, Vietnam, South Korea, Thailand, Taiwan, and Singapore. The first US case was announced on Tuesday, and five US airports have begun screening for the virus after a man in his thirties from Snohomish County, Washington, had his infection confirmed by a recently developed genetic test. (A potential second US case was announced today.) And on Thursday, Chinese officials quarantined a number of cities in close proximity to the center of the outbreak, Wuhan. Public transportation was shut down, roads were blocked, and outbound flights were suspended, leaving 20 million people effectively unable to leave on the eve of the Chinese Lunar New Year.

While the World Health Organization has so far stressed that this isn’t a global emergency, online rumors and lies have run fast.

The crux of Sather’s conspiracy hinges on a 2015 patent filed by the Pirbright Institute in Surrey, England, which covers the development of a weakened form of a coronavirus that could potentially be used as a vaccine to prevent respiratory diseases in birds and other animals. This is a standard way that vaccines are made, for everything from the flu vaccine to the polio vaccine.

“The assignee of this patent was the government-funded Pirbright Institute out of the UK,” Sather tweeted. “Was the release of this disease planned? Is the media being used to incite fear around it? Is the Cabal desperate for money, so they’re tapping their Big Pharma reserves?”

One of the many, many issues with Sather’s theory is that the Pirbright does not currently work with any strains of the coronavirus that affect humans — its patent covers the avian coronavirus, which only affects birds. (Scientists have suggested that snakes or mammals could be the source of the outbreak — not birds.)

Dr. Erica Bickerton, who studies avian pathology for Pirbright, told BuzzFeed News that the institute patented the avian coronavirus to study how it replicated in chickens and chicken cells.

“The name coronavirus is a whole family of viruses,” she said. “Each of these viruses has their own characteristics.”

Bickerton said she was aware of the misinformation spreading online, but stressed that none of Pirbright’s work with the coronavirus involved humans: “The work we do focuses on an avian coronavirus that affects chickens.”

But the facts haven’t slowed down the hoax.

“Big money in vaccines,” one QAnon supporter tweeted. “Who is pushing for people to be vaccinated? Hillary and Chelsea?”

According to CrowdTangle, the institute’s patent listing has been shared over 6,000 times in the last week. Facebook Groups like QAnon QClearance 8chan + related articles 2 Staqe 2 and Georgia Coalition for Vaccine Choice have linked the page to their thousands of followers, accusing Pirbright of being behind some kind of nefarious plot, which extends to the very social media company that hosts them.

“This is a man-made, patented virus with a vaccine in the works. Here’s the link to the patent,” one user wrote in a group called United States for Medical Freedom. “So back in Nazi Germany, Hitler didnt want anyone to wake up to his deceit. So he had Jews in every neighborhood give the S.S. intel. Kind of like facebook reporting our comments.”

Sather, who appears to have started the false rumor, has over 100,000 followers on Twitter and over 200,000 followers on YouTube, where he records videos about QAnon, the evidence-free mega-conspiracy theory that claims Donald Trump was appointed president by the military to save the nation from a ring of pedophilic Satanists, which includes Bill Gates.

Paranoid social media users found Google search results that connect the Pirbright Institute to a Bill & Melinda Gates Foundation grant to study livestock antibodies — and latched on to it.

“And would you look at that, some of [Pirbright’s] major funders are the World Health Organization and the Bill & Melinda Gates Foundation,” Sather tweeted.

Other conspiracy theorists have supplied a purported motive: “Bill & Melinda Gates Foundation one of the primary owners. Deep State released the virus to create chaos since nothing stopping Trump,” reads another user’s heavily retweeted post about the patent.

According to Teresa Maughan, a spokesperson for Pirbright, not only does the patent in question not involve a coronavirus strain that affects humans, but the institute’s work with the virus wasn’t funded by the Gates Foundation.

“The patented work cited in the conspiracy theories involved infectious bronchitis virus (IBV) only, and we made four changes in the gene responsible for replicating the virus’s genetic material. This has weakened the virus so it is no longer able to cause disease and has potential to be used as a vaccine, but has not yet been developed,” she told BuzzFeed News. “The patented work was completed in 2015 and is not funded by the Bill & Melinda Gates Foundation.”

Nevertheless, Sather continues to tweet rumors and lies about the coronavirus. “You see how they try to implant thoughts into your head,” he wrote on Wednesday in a post about the virus that has been retweeted almost 1,000 times. “Fear sells.”