Sarah Mergens showed signs of obsessive-compulsive disorder long before she was diagnosed with it as an adult. It initially took the shape of harmless quirks, like organizing dinosaur toys by shape and color. More debilitating symptoms crept in as she got older, such as being afraid of public doorknobs or worrying that she'd use a bad egg when baking and cause someone she loves to become ill.

As an adult, Mergens, 27, held her OCD symptoms at bay through exposure and response prevention therapy, supportive friends and family and internal pep talks. Then COVID-19, the disease caused by the coronavirus, began to spread and threatened to set her back on the progress she's made in convincing herself that her fear of circulating an illness is overblown. The virus, she said, is her "personal nightmare."

"I can't think of another event that's hit me like this has," said Mergens, a psychotherapist who lives in the Minneapolis area. "Suddenly everything that I told myself again and again until I believed it was true is in direct contradiction to what my boss, the government and the community were telling me."

Her thoughts became an endless stream of "what ifs." What would happen if she was quarantined? Will she contract the virus? Could someone she cares about die after getting the virus from her? When she washes her hands hourly or disinfects her entire office each day, she tells herself: "This is from the outside. This is not a Sarah thing. This is not OCD. This is necessary." But it doesn't stop her racing thoughts, and she worries that her extra vigilance will be hard to shake.

"I'm afraid that I'm going to want to continue those when the crisis is over," Mergens said of her constant hand-washing and sanitizing, "and as a result, really take steps back in my progress."

Unlike anything they've seen before

Over 2 million Americans are estimated to be affected by OCD, according to the Anxiety and Depression Association of America. Nearly 7 million people in the U.S. are affected by generalized anxiety disorder and about 6 million by panic disorder. While the concern about the COVID-19 pandemic has upended the lives of Americans from all walks of life, interviews with people with mental health issues — including anxiety, bipolar disorder, OCD and panic disorder — as well as counselors who are treating them, reflect a particular chaos the virus has caused.

Many people with these disorders are going through a wave of similar emotions and thoughts. They fear getting someone else sick, even if they aren't showing symptoms. Those who already keep hand sanitizer and disinfectant with them at all times suddenly can't find those products at stores thanks to panic shoppers. Some behold the irony that their daily routine of hyper-cleanliness is suddenly everyone else's reality, while others feel thrown off by the government's telling them that to prevent coronavirus spread, they need to do all the excessive cleaning and isolating that they've previously tried not to do to control their mental health disorders.

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As more events, schools and services have been canceled, the nonprofit Crisis Text Line saw an increase in people reaching out for help because of the coronavirus, the intervention hotline said Monday. As of March 13, COVID-19 was mentioned in 15 percent of all conversations on the Crisis Text Line. On Reddit, forums for people with OCD are full of users sharing memes related to COVID-19 and their community, describing how social distancing is giving them more time to worry and asking for support with the fear that has taken hold of them.

Mental health counselors say the wave of anxiety sweeping their patients in clinics is unlike anything they've seen before.

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"This one is so broad, and you know everyone is being exposed to this particular fear — I think it's unraveling lots of folks," said Reid Wilson, director of the Anxiety Disorders Treatment Center of Durham and Chapel Hill, North Carolina.

One of Wilson's OCD clients nearly canceled an appointment because they were concerned they had touched their nose too much and could give the coronavirus to Wilson, he said. Another, with generalized anxiety disorder, couldn't stop worrying about whether their daughter traveling from another country was at risk.

"Uncertainty is the basis of all anxiety disorders, so in some ways, COVID-19 has set a fire to the foundation of anxiety," said Christina Maxwell, a counselor at the Anxiety Treatment Center of Greater Chicago.

Maxwell said every patient she's seen in the past few weeks has had anxiety related to COVID-19. She's also received calls from people who have never struggled with anxiety before but are now having difficulty coping with work or school changes, loss of income or being in close proximity to an estranged spouse for a long period of time.

"The concerns are numerous and severe," Maxwell said.

'Your normal has become everyone else's normal'

For Tam Sanders, 28, a Cincinnati resident, it's not the virus that makes her afraid; "it's other people's hysteria and panic that makes me most anxious."

"Suddenly everyone is like you. Suddenly everyone feels they need disinfecting wipes and hand sanitizer as much as you feel you do, every single day of your life," Sanders said. "Your normal has become everyone else's normal."

A 24-year-old transgender man with social anxiety and panic disorder living in Hollywood, Florida, who has spent the past couple weeks trying to replenish their hand sanitizer, had a similar sentiment.

"I think most people without anxiety issues don't understand that for us with anxiety disorders, this fear everyone's feeling is our everyday life," said the man, who asked that their name not be published to protect their privacy. "If there's anything to take away from this terrible virus, it's that people finally understand how some of us feel every single day."

Molly Grace Larson, 20, a student at the University of Wisconsin-Eau Claire who has been treated for panic disorder and OCD, said seeing panic buyers clear the shelves exacerbated her stress and made it more difficult for her to compartmentalize. She's become more neurotic about washing her hands lately, she said.

"It makes me feel like I'm not doing enough," Larson said. "Maybe I should be buying hand sanitizer in bulk. But I don't know — nobody really knows how best to respond to this kind of crisis."

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Faryl Zaklin, 48, who lives in San Diego, said she started canceling appointments and workouts in early March to mentally prepare herself for social distancing before businesses began closing, even though that meant depriving herself of tools she uses to manage her OCD. She worries that the fallout from COVID-19 could upend her progress, turning her back into a chronic hand-washer who often uses disposable gloves and struggles to leave the house.

"What's more scary to me is having an OCD relapse — that's worse than my fear of getting this virus," Zaklin said.

The most effective behavioral forms of treatment of obsessive-compulsive disorder include exposure, response prevention and cognitive therapy, which require people to go through what they're most afraid of to realize that their fears are unfounded. So if people feel they must wash their hands every time they touch a door handle, this treatment would help lead them to see that nothing bad will happen if they don't. However, that isn't necessarily true right now.

"When everyone else comes on TV and starts saying 'wash your hands as often as you can,'" Wilson said, "that's opening that door for people with the disorders to give up their routines."

Wilson said he's offering similar advice to clients as he always has, encouraging them to set up rules they can follow, such as how often they'll allow themselves to clean their homes or when they'll wash their hands without impeding daily life.

"These worries pop up in your head, and you can't control that," Wilson said, "but you can control what you do next."