President Donald Trump confessed Wednesday that for the last few weeks he's been missing something: touching his face.
"I haven't touched my face in weeks," Trump said during a meeting about coronavirus with airline executives. "I miss it."
He's not alone.
The emergence of a new coronavirus around the world has triggered widespread warnings about personal hygiene and habits in an effort to limit its spread: wash your hands, limit unnecessary travel and don't touch your face.
It's that last piece of advice that's a challenge for many people.
"Realizing basically all I do is touch my face," tweeted actor Seth Rogen.
"Did not realize how often I touch my face until the CDC explicitly told me not to touch my face," tweeted author Allison Raskin.
On social media, scores of people have lamented their fears that their inability to stop touching their faces will cause them to catch the new coronavirus. The anxiety surrounding face touching is just one way stress over the coronavirus has manifested in the general population.
And the warnings themselves may be causing more face touching — and associated anxiety — than intended.
The tweets about face touching point to a problem that health professionals are warning can be as pervasive as the coronavirus itself. Although many of the tweets about face touching are tongue-in-cheek, the palpable anxiety over contagion is not.
"Fear and hysteria are the biggest things we fight other than the virus itself," said Joseph Fair, a virologist and outbreak response specialist. "Fear, hysteria, hoaxes, conspiracy theories, everything else — 50 percent if not more of containing the outbreak is that, be it this outbreak or others."
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Fears over face touching have become the hallmark of anxiety surrounding the coronavirus' spread, and anxiety manifesting as behavioral changes is common, experts told NBC News. Whether it's people buying surgical masks, staying home from work or panicking about touching their faces, most people's fears are overblown, said Fair, an NBC News contributor.
"I think the biggest fear people should have is that this could do a lot of harm to our elderly community. … The biggest irrational fear is 'Oh, my God, I'm going to get coronavirus, I'm going to die,'" Fair said. "Overwhelmingly, the numbers show that's not going to be the case."
While there are communities whose fears of coronavirus are founded, the behavior of less at-risk communities could fan the flames of hysteria among people who are able to fight off the illness.
Dr. Timothy Scarella, an instructor in psychiatry at Harvard Medical School, said that what might be accepted as rational behavior in Wuhan province in China, the site of the coronavirus outbreak, would likely be considered irrational behavior in Boston.
"If someone bought a pack of surgical masks and feels better having them in their living room and that's it, it's not the end of the world, versus somebody who hasn't left their house in three weeks and says, 'I'm not going to leave until this is settled,'" Scarella said.
Both professionals agreed that practical steps of practicing good hygiene are the best ways for the general population to avoid coronavirus, but they said face touching — the biggest source of fear expressed on social media — is going to be a hard habit to break.
"It is absolutely [human nature]. I think that to ask people not to touch their face is kind of ridiculous. It just can't happen," Scarella said.
He equated that particular anxiety to the everyday nagging feeling that someone left home without turning off the lights.
"People are saying: 'Wait a second. Did I just touch my face? Or did I not? I don't think I did, but maybe I did when I wasn't thinking about it.' And, honestly, maybe they did," Scarella said.
Scarella said it is common for people to end up fixating on these kinds of thoughts.
"People with a lot of health anxiety or anxiety in general often engage in this kind of recursive, ruminative kind of checking," Scarella said.
Scarella said the coronavirus has been ideal for preying on people's anxieties because of the ambiguity surrounding it.
"I think whenever you're talking about something that's transmissible or infectious there's a particular type of panic that goes on, especially in the early stages of this one, where there was a lot of uncertainty … which stoked fears," he said. "There's not a lot of reassurance for people."
Scarella said one possible danger of the growing concern around the coronavirus is the treatment of those perceived to be from regions where the infection was first discovered. He likened it to the hysteria around the AIDS crisis in the 1980s.
"I have a colleague who remembers a town hall where someone said, 'We should throw gay people on Long Island and quarantine them,' which is obviously ridiculous," Scarella said. "But he was saying these people were panicked. They didn't know what to do."
Scarella said that because the illness originated in China, he had concerns about panic manifesting in the way people treat those they believe to be from regions where it was first identified. In the United States, Asian-owned establishments have reported a drop in business, and Asian American lawmakers have urged members of Congressto help curb coronavirus-based xenophobia.
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While both experts said trying to minimize face touching is the same advice they give during cold and flu season, they agreed that even if people do touch their faces, it's not the end of the world.
"I think if you talk to virologists or other people who have been working on this, this is not the one that's going to wipe us all out," Fair said. "This isn't going to be the end of humanity."