In The Plague, Albert Camus tells the story of a deadly virus that spreads through the Algerian coastal city of Oran. It halves the city’s population, killing five hundred people a week at its peak. As the surviving population struggles to stay alive, there’s an increase in fires: people returning from quarantine in a state of panic set their homes alight in a desperate attempt to kill the plague.

It’s madness. But it’s not difficult to imagine people resorting to similar actions now, influenced by misinformation about how to stave off the novel coronavirus. Most of us would also take desperate measures to evade death. And indeed, unreasonable desperate measures are multiplying during the Covid-19 pandemic.

Gary and Wanda Lenius, a couple in their sixties living in Arizona, drank a toxic chemical called chloroquine phosphate, used for cleaning fish tanks, thinking it could protect them from Covid-19. They consumed the substance as a prophylactic after seeing Donald Trump tout the malaria drugs chloroquine and hydroxychloroquine as potential coronavirus treatments. The name partly matched a product they had used for treating their fish. But the toxic liquid they ingested was different from the medicinal form used to treat malaria.

Within twenty minutes, they became extremely ill. Gary died and Wanda was left in a critical condition for several days. “Trump kept saying it was basically pretty much a cure,” Wanda told reporters. “We were afraid of getting sick.” So were the Oranian citizens who set their own homes alight to ward off the plague.

Trump’s medical advice has been misleading and irresponsible on many occasions, false on others, and has recently become downright preposterous. In a White House briefing on March 19, Trump wrongly claimed that the US Food and Drug Administration (FDA) had approved hydroxychloroquine to treat Covid-19. In that same briefing, Trump said hydroxychloroquine has “been around for a long time, so we know that if it—if things don’t go as planned, it’s not going to kill anybody.” Several times he’s also said, “What do you have to lose? Take it.”

The FDA’s post-briefing statement made clear that they had not yet approved any drugs to treat coronavirus. Anthony Fauci, the director of the National Institute of Allergy and Infectious Diseases and Trump’s top infectious diseases adviser, said the next day that there was no evidence that hydroxychloroquine could be used as an effective preventative measure against the coronavirus. Several studies have since concluded that hydroxychloroquine is not only ineffective at preventing or treating Covid-19 but is also potentially fatal.

Last month, Trump’s medical advice reached the level of absurdity. In a White House briefing on April 23, he suggested that scientists should investigate whether injecting disinfectant into the human body, or shining ultraviolet light inside, might be effective against Covid-19. These comments provoked immediate public warnings from doctors, health reporters, and disinfectant manufacturers that people should not attempt to self-medicate with disinfectant. In the days following Trump’s extraordinary suggestions, there was an increase in cases of disinfectant exposure in New York, and hundreds of calls from Maryland residents to a state hotline about injecting or ingesting disinfectant. Two men in Georgia were hospitalized after trying to self-medicate by drinking household cleaning products.

Most recently, Trump stated that he’s taking hydroxychloroquine himself. He’s presumably taking it as a prophylactic, since he claims that he does not have Covid-19 and tested negative for the virus in March. Despite the documented risks and the incidents that have occurred from people self-medicating following his advice, when Trump proudly announced to reporters that he was taking the drug, he again asked, “What do you have to lose?”

Trump’s irresponsible advice risks increasing public panic and decreasing trust in authorities. It immediately drew criticism from medical experts. Carlos del Rio, an expert in infectious diseases at Emory University, expressed concern that Trump’s statements could give rise to a conspiracy theory that evidence of the drug’s effectiveness is being withheld from the public.

During a crisis in which panic-buying has led to empty supermarket shelves and a surge in gun sales, we all need to be careful of the information we disseminate. After all, people are taking severe measures to mitigate the risks of catching or spreading Covid-19 on the basis of the latest news and social media posts. But those in positions of power need to be particularly careful, because many people act directly on their advice. The New York Times reported a surge in prescriptions for chloroquine and hydroxychloroquine since Trump’s promotion of them.

The amount of misinformation in Trump’s briefings even generated a debate over the responsible way to cover them. The New York Times and The Washington Post temporarily boycotted the briefings. While we all have the right to hear what Trump says in press briefings, they should come with a health warning—and perhaps also one about human nature: when we panic, even a sliver of evidence for a belief can be enough to make us act on it.

In 1942, after writing The Stranger, Albert Camus told the statesman André Malraux that he was writing a new novel about a plague in order to understand what it means for humanity. We are now learning the reality of what it means. A seemingly insignificant trip to a grocery store can be deadly. Spreading misinformation in a time of crisis can cause panic which can have dreadful consequences.

Camus the existentialist found a remarkably sentimental and humanist meaning in the plague of Oran. In one of the most memorable passages in The Plague, the lead city doctor, Bernard Rieux, expresses his overarching principle for confronting the virus to Raymond Rambert, a Parisian journalist trapped in Oran by the quarantine. “I have to tell you this: this whole thing is not about heroism,” Rieux says to Rambert. “It’s about decency. It may seem a ridiculous idea, but the only way to fight the plague is with decency.” Rambert then asks Rieux what decency is. Rieux replies, “I can’t say, but in my case I know that it consists in doing my job.”

Rieux shows us that truth, decency, and a job well done in a time of crisis really matter. That is what the plague really means for humanity. Unfortunately, it’s a lesson Donald Trump, the most powerful leader in the world, has yet to learn.

Jonathan Beale is a Visiting Research Fellow in Philosophy at the University of Hertfordshire and co-editor of Wittgenstein and Scientism. @DrJonathanBeale