Marilyn Schneider is an executive secretary at Ohio'Cleveland Clinic where she gets her temperature checked several times a day.
But it wasn’t until the 57-year-old got home from work on March 27 that an intense chill suddenly overcame her, accompanied by a rising fever.
“It felt like something came up behind me and dropped a bucket of ice water on me,” she said.
The next day she got tested and less than 12 hours later learned she was positive for COVID-19. Her fever climbed from 98 to 104.5 degrees Fahrenheit in a single day, then the hallucinations began.
At first, Schneider heard voices through the walls that sounded like neighbors talking or her son in the next room – even though she lives alone and her son lives in Michigan. Soon she began calling for her dog, Scruffles, who died seven years ago.
It culminated one night when Schneider was in bed and heard voices again. She turned over and was suddenly face-to-face with herself, a double, lying next to her on the bed. The vision's eyes were wide with fear, its arms extended out, saying repeatedly, “Marilyn, why aren’t you helping me?”
Schneider reached through the hallucination to grab her cell phone on the nightstand and called 911. The next thing she remembers is running out to the street at 4 a.m. to flag down the ambulance. Doctors told her at the hospital if she hadn't made that call she would have been dead by morning.
“The COVID hallucinations saved my life,” she said.
Dr. Pravin George, a neurointensivist at the Cleveland Clinic, says hallucinations and delirium are becoming more common among COVID-19 patients. However, it’s rare for someone to distinguish a hallucination from reality and then remember it afterwards – like Schneider.
“The fact that she was able to do a lot of those things is pretty remarkable,” he said. “Most of the patients aren’t able to remember a lot of these things happening.”
While experts still can’t confirm why COVID-19 patients experience hallucinations, George offered a few explanations.
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It’s well-known now the coronavirus can trigger intense inflammation caused by an overreaction of the body’s immune system. George says hallucinations could stem from such inflammation blocking blood to the brain or from the virus attacking the brain itself. Low oxygen levels from impacts to the lungs also can cause delirium.
COVID-19 patients who are heavily sedated in the ICU can experience a different kind of delirium, called hypoactive delirium, George says.
The Cleveland Clinic notes symptoms of hypoactive delirium include withdrawal, apathy, laziness and decreased responsiveness. Hyperactive delirium is characterized by anxiety, restlessness, rapid changes in emotion and hallucinations.
SARS-CoV-2, the virus that causes COVID-19, isn’t the first to lead to hallucinations and delirium. According to the Mayo Clinic, chickenpox, measles and tick-borne or mosquito-borne viruses can cause brain inflammation, medically known as encephalitis.
While Schneider's hallucination forced her to seek help, her condition didn’t improve at the hospital. When she arrived at the trauma center, the doctor said her lungs were the consistency of chocolate pudding.
“I said, 'Please cover up the windows, I don’t want my co-workers to see me die,'” she recalled.
Schneider called her family to tell them her wishes and to say goodbye. She'd survived cancer, a double mastectomy and graduated college the year before, but she didn't have any fight left in her to conquer COVID-19.
But then another hallucination appeared. As she laid in the hospital bed intubated and heavily sedated, her late husband, aunt, sister and grandmother appeared in the room with a message.
"These people were telling me I had to go back and had to fight," she said.
Schneider's condition improved after that last hallucination. She was taken off the ventilator after several days and released from the hospital the following week.
She's still mentally, emotionally and physically recovering from her illness. The vivid hallucinations she says saved her life prompted her to seek counseling, something she recommends for other COVID-19 patients.
"Hallucination, drug induced, spiritual or whatever it is … I don’t want to experience it again before it's my time," she said.
"It was a very scary time. I’m not minimizing cancer in any sense of the word ... (but) I would rather go through cancer again than go through COVID again."
Health and patient safety coverage at USA TODAY is made possible in part by a grant from the Masimo Foundation for Ethics, Innovation and Competition in Healthcare. The Masimo Foundation does not provide editorial input.
Follow Adrianna Rodriguez on Twitter: @AdriannaUSAT.