As the coronavirus death toll rises, some Trump allies are making the dubious claim that people across the country already contracted the disease months ago—and unknowingly recovered from it before the crisis even began.

“I had it in January,” trash-talking former White House adviser Sebastian Gorka told his talk radio audience on Tuesday. “I had the longest cough, they put me on one of these little inhaler thingies, and I think I had it back in January. And I’ve heard this story so many times.”

Gorka said he had contracted the coronavirus after being prompted by a caller, who himself suspected he had himself recovered from the illness because he felt sick over the winter. Gorka claimed that his own then-unidentified coronavirus infection was so mild, he didn’t even have to stop his radio show.

“I have a radio show, they didn’t let me stay in bed,” Gorka said. “I think you’re right, I think we’ll find out that many, many more people have had it, and that’s why the mortality figures are going out to be much better than we expected.”

Asked by The Daily Beast whether he had received any test for the coronavirus or its antibodies, notified people around him that he had the disease at the time, or could explain what he meant by an “inhaler thingy,” Gorka demurred.

“Go to Hell you fetid hack,” he wrote in an email.

Gorka isn’t the only Donald Trump ally promoting the idea that Americans who felt sick over the winter secretly had the coronavirus. From prominent media personalities to internet blog commenters, Trump supporters are claiming that they have already survived the coronavirus before it appeared in significant numbers in the United States, and that they thought it was just the flu or another illness at the time and are now immune.

Pro-Trump personality Kambree Kawahine Koa told her more than 200,000 followers that “half the country has had Covid-19” and was instead treated for flu. Comment sections on conservative sites like Townhall and The Gateway Pundit are filled with people claiming that, because their communities had what they believed was a “bad flu” over the winter, they’re now immune from coronavirus.

“Did I have #Corona?” tweeted DeAnne Lorraine Tesoriero, a former GOP congressional candidate pushing a conspiracy theory about coronavirus and empty hospitals. “Hmm.”

Recently released data from China suggests that as much of a third of positive coronaviruses could be asymptomatic, meaning that people in the United States could be contracting and spreading the virus without realizing it. According to Dr. Timothy Brewer, though, there’s a much simpler explanation for why a person could have felt sick in the late fall and early winter: people often get sick from other illnesses, like the flu, during the winter.

“This was a very active flu season, and so most people who felt sick in December, January, or Feb either had influenza or another respiratory virus other than Covid-19,” Brewer said.

Trump supporters aren’t the only people who appear to be conflating a bad flu season with the coronavirus. Medium publication GEN noted that Twitter has been deluged with claims from people tweeting that they’re “near 80% sure” or “96% sure” they already had the coronavirus last year.

The idea that the coronavirus infected people months ago without anyone knowing has a special appeal to the Trump faithful, in that it promotes the notion that the fatality rate for the disease is lower than experts have claimed. That may, indeed, be true, though mortality rates appear to be differing across countries, states and even counties. But the argument still also poses public health risks in that it could convince people, wrongly, that they’re already immune simply because they experienced flu-like symptoms in the fall.

There’s currently no way for someone who thinks they have already recovered from the coronavirus to see if they had it, because there’s no FDA-approved antibodies test. It’s also not clear what immunities, if any, coronavirus patients build up.

“The concern is that people who think they may have had it may falsely believe that they are protected and make themselves susceptible to the virus by being less careful with their personal behavior in terms of visiting or being in close contact with people with symptoms of cough or fever,” said Dr. Jeffrey D. Klausner, a professor of medicine and public health at UCLA.

The idea that anyone who was sick in November, December, or January likely had coronavirus appears to have been fuelled by a series of viral Facebook posts.

“Who got sick in November or December and it lasted 10 to 14 days, with the worst cough that wouldn’t go away?” one widely circulated anonymous post reported by USA Today reads. “If you can answer, yes, then you probably had the coronavirus.”

The Trump administration has said it first caught wind of the coronaviru from reports from China in early January. The first United States coronavirus case was detected later that month from a person who had traveled to Wuhan province—the pandemic’s origin point. That makes it highly improbable that Gorka, his caller, or any of the others who had no close contacts with China would have contracted it before the first documented U.S. case.

“It is very unlikely they were infected with COVID-19,” Professor Lawrence Gostin, a professor of global health law at Georgetown University, told The Daily Beast. “At that time the virus was circulating primarily in China and unless they had close contact with someone who had just traveled from China, they are almost certainly disseminating false information.”