They’ve been around for a long time and flourish in a crisis. Conspiracy theories may seem absurd and harmless to some — but they can do damage.

Let me start with a health warning: the three assertions you are about to read are untrue. 

The Russian influenza outbreak of 1889-1891 was sparked by electric light. Germany set out to infect enemies in World War One with Spanish flu. HIV was created in American laboratories and shipped to Africa.

Each statement is false. And each appeared in contemporary media reports.

“A new theory as to the cause of influenza is being ventilated by some Paris physicians,” the British newspaper The Bristol Times and Mirror reported on January 22, 1890. “These gentlemen maintain that the epidemic is due to an excess of electricity in the air.”

The piece went on to claim that the resulting “superabundance” of ozone had been known to cause flu-like symptoms in animals.

“To counteract the effect of over-electrified air, influenza patients are therefore recommended to inhale ammonia, and to allow the same substance to evaporate in their rooms.”

COVID-19 has sparked a rash of conspiracy theories.

From our lofty 21st Century vantage point, it is easy to identify this as terrible advice, given that we now know ammonia can irritate and even burn our airways and skin.

Yet the scientific knowledge we have accumulated in the ensuing 131 years has not been enough to shield humanity from equally unlikely—and often dangerous—conspiracy theories that have spread during the current pandemic. 

One of the earliest was that breathing problems found in those with the most acute cases of COVID-19 were caused by 5G telecommunications masts built by China’s Huawei.

Another is that the new coronavirus was engineered in a laboratory and, accidentally or intentionally, released into the world. The lab was supposedly in Wuhan, the city in China where the outbreak began. Or in the U.S. Centers for Disease Control and Prevention in Atlanta. Or the virus was created by Microsoft billionaire Bill Gates so he could turn a profit on vaccines. Or microchip the world. Or something like that. 

“We’re not just battling the virus,” World Health Organization Director-General Tedros Adhanom Ghebreyesus said recently. “We’re also battling the trolls and conspiracy theorists that push misinformation and undermine the outbreak response.”

Adherents want an explanation in time of crisis.

These latest conspiracy theories echo many of the older pandemic-driven narratives. They seek to blame a new technology. Or the machinations of an enemy. Or a scapegoat. Or they deny or dismiss the threat altogether.

According to Dr. Karen Douglas, Professor of Social Psychology at the University of Kent and author of several studies on conspiracy theories, they all share one other trait: They offer adherents an explanation for the inexplicable in a time of uncertainty. 

“Research suggests that people believe in conspiracy theories in the hope that they will satisfy important psychological needs—even though they most likely don’t help,” she said in an exchange of emails. “Specifically, people have a need for knowledge and certainty, to feel safe, secure and in control, and to feel good about themselves.”

These needs—to feel in the know, in control or part of a group—sharpen in times of crisis, she said. This is why conspiracy theories spike during epidemics, disasters and geopolitical upheaval. Recent years, punctuated by extreme weather events, a rise in right-wing populist politics and mass migration, offer an ideal breeding ground.

Because different myths can satisfy different needs, it is difficult to pinpoint a particular personality type or background that makes one person more credulous than another, although Douglas said those on the political extremes—left and right—are more inclined to believe misinformation. 

Psychologists have been trying for 30 years to build a working profile of the kind of person who buys into conspiracy theories, Dr. Jovan Byford, Senior Lecturer in Psychology at the UK’s Open University, said via email. But the focus on the individual is misplaced, he said. 

“Conspiracy theories are not an issue of individual psychology,” he said. “They are a social problem. The question we need to consider is not who believes in conspiracy theories, but why, especially in times of crisis and turmoil, conspiracy theories come to be seen by so many as an attractive, plausible and acceptable point of view.”

Some leaders have fanned certain theories.

Most of us might laugh off the most improbable theories—such as the argument that the Earth is flat and Australia doesn’t exist. But some can have a harmful or even deadly impact on both believers and society. 

“Historically, epidemics of infectious diseases have often been attributed to human agency and have led to scapegoating of ethnic and religious minorities,” Byford said, noting that, according to some estimates, AIDS-related conspiracy theories in the 1980s and 1990s contributed to hundreds of thousands of deaths in sub-Saharan Africa.

The conviction that 5G is the culprit behind COVID-19 has prompted attacks against mobile phone towers across Europe. The belief that China purposely introduced the virus has led to racist attacks and verbal and online abuse. The $350 million that the Bill and Melinda Gates Foundation has committed to the global detection and treatment of the coronavirus has earned Gates as much hatred as it has plaudits.

The amplification by the leaders of the United States and Brazil of certain early conspiracy theories—that COVID-19 is no more serious than the flu and that it will one day “just disappear”—are viewed by many as being at least partly responsible for comparatively high infection and death rates in the two countries. 

Although U.S. President Donald Trump has stopped dismissing the virus as a Democratic “hoax,” he seldom wears a mask in public and has offered misleading or false information at news conferences.

Brazilian President Jair Bolsonaro has repeatedly called the virus “a little flu,” flouted social distancing rules even after testing positive himself and promoted an unproven treatment. 

A pair of falsehood-filled videos — Plandemic and its longer sequel, Plandemic: Indoctrination — have fanned COVID-related myths. Facebook has banned users from sharing the link to the second video, saying it touted “COVID-19 claims that our fact-checking partners have repeatedly rated false.”

Both videos hinge on interviews with discredited scientist Judy Mikowits, who lists claims that are either unsubstantiated or false. Mikowits’s best known research, which related to Chronic Fatigue Syndrome, was withdrawn in 2011 by the journal Science because of flaws in data. She has since become a prominent vaccine opponent and fierce critic of Anthony Fauci, Director of the U.S. National Institute of Allergies and Infectious Diseases and an expert on COVID-19.

Conspiracy theories are nothing new.

While social media platforms allow misinformation to spread, conspiracy theories are not themselves a product of social media. It is true that Facebook’s algorithm, which promotes content that aligns with a user’s views, offers malicious actors a chance to air false narratives and can create echo chambers. But Douglas says this does more to reinforce pre-existing ideas than to convert non-believers.

“Conspiracy theories have been around for centuries,” Byford said. “What we are experiencing now is nothing unusual. But there is little comfort in that thought, as conspiracy theories are still very bad for our own health and for the health of our democracy.”

Even though misinformation pre-dated social media, critics of Facebook and Twitter say the platforms are nonetheless responsible for the veracity of the content they carry. “I think they are making some important steps in that direction, but there is a long way to go,” Byford said.

Meanwhile, the WHO is trying to cure what it terms the “infodemic”. It is working with companies such as Viber, TikTok, WhatsApp and YouTube “to ensure that science-based health messages from the organization or other official sources appear first when people search for information related to COVID-19.”

In high-stress periods such as today, conspiracy theories can have a toxic impact on even close relationships. This is why it is important to take the right tack when addressing beliefs held by family or friends. 

“Making fun of the person or being hostile to them might backfire and alienate the person further,” said Douglas. “Many of these people already feel marginalised, and these strategies are likely to make that worse.”

Think twice before sharing.

In The Conversation, an online magazine for academics, Byford sets out six tenets for constructive engagement with conspiracy adherents:

• Understand it won’t be easy—conspiracy theories are often deeply lodged and immune to even the most rigorous evidence.
• Be prepared that you may arouse strong emotions and try to de-escalate the situation if needed.
• Drill down into the nature and content of beliefs so you can discuss them in detail.
• Find common ground and acknowledge any well-founded concerns that might have contributed to this conviction.
• Focus on facts—and be respectful.
• Recognise that you may not, in the end, succeed in arguing them around.

“I think a good approach might be to appeal to the person’s desire for critical thinking,” Douglas said. “Many conspiracy theorists view themselves as critical thinkers…. So perhaps one strategy might be to ask the person to think critically about where they are getting their information: is the source reliable or unreliable, etc.”

Byford, too, advises focusing on logic and, if they seem open to hearing it, reminding believers that no widely held conspiracy theory has so far turned out to be true.

“Numerous actual conspiracies, cover-ups and scandals have been uncovered over the years, but never by a conspiracy theorist,” he said. “Most have been uncovered by mainstream journalists and media outlets, or by state agencies. And that is the problem. Conspiracy theorists are so obsessed with large, evil and far-fetched plots full of cartoon villains, that they miss plenty of actual bad things happening under their noses.”

Meanwhile, we would all be advised to be careful about the information we consume, and to take a moment to verify what we read before sharing it with others. 

Three questions to consider:

1. Do you know anyone who believes in a conspiracy theory?
2. Have you ever believed something and then changed your opinion after delving into the facts?
3. Are you careful about verifying posts before sharing them with your wider friend and follower community?

Sarah Edmonds has been a journalist for three decades. She spent 27 years with Reuters in seven countries on three continents as a reporter, news editor, bureau chief and news operations manager. She is also a daughter, niece, former student and friend of dozens of people who are staying safely inside.