It’s called “Long Covid,” and Smith is a member of a particularly susceptible population. In a new U-M study, one in four women reported symptoms lasting more than ninety days, compared to one in six men.
“I didn’t need to be hospitalized, but I had a pretty serious case of Covid-19,” Smith says. “For the first week, I felt the way you do when you know you’re getting the flu.” But even after she recovered, she just couldn’t seem to shake certain symptoms.
“For a while, I told myself it was all in my head,” she recalls. But then she started reading about Long Covid, “and realized I’ve got it!”
In addition to women, older people and Hispanic and Native American populations were also significantly more likely to report prolonged symptoms. So were Michiganders who’d been hospitalized, had no more than a high school education, had annual incomes under $50,000, and those with preexisting medical conditions. Of the latter, patients most at risk are those who are immunosuppressed or have conditions like COPD and emphysema.
The study launched early in the pandemic, when officials from the Michigan Department of Health and Human Services asked the U-M School of Public Health to help track how patients recovered. “To our knowledge, this is the only Covid-related demographic study of an entire population,” says assistant research scientist Jana Hirschtick. She worked with Nancy Fleischer, associate professor of epidemiology and principal investigator; postdoctoral fellow and report coauthor Elizabeth Slocum; student interns; and professional interviewers.
“At the time these people tested positive, there were no reliable at-home tests, and every PCR test in Michigan was reported to the Department of Health,” Hirschtick explains. “We looked at them all—those who were asymptomatic, those with mild to moderate cases, and those who required hospitalization and ventilation—and then we drew random names from all over the state. We sent a letter requesting that the individuals take a one-hour survey, either online or over the phone, to help us record and determine what was happening.” Eventually, 2,073 agreed to participate.
Gradually, the researchers realized that a significant number of their interviewees continued to struggle with Covid-type symptoms for weeks or even months after their diagnosis. They adopted the World Health Organization’s definition of Long Covid as “prolonged or persistent symptoms lasting at least ninety days.”
The most prevalent symptoms are fatigue, loss of sense of smell and/or taste, and memory loss/disorientation (“brain fog”). Some respondents also complained of shortness of breath, general weakness, muscle weakness, joint pains, and hair loss.
“Clinics, hospitals, physicians, and the public health system need to be aware that [Long Covid] is an ongoing part of the pandemic,” Fleischer told Michigan News. According to the study, nearly 38 percent of patients had not completely recovered within thirty days, 26.5 percent hadn’t recovered within sixty days, and 21.4 percent were still exhibiting symptoms at ninety days.
Half of those who were hospitalized or reported “very severe” cases had lingering symptoms, as did Michiganders with annual household incomes under $50,000. Body mass also appears to play a major role. Forty-five percent of those with Long Covid symptoms were classified as overweight or obese.
People with no more than a high school degree (29.4 percent) were also much more likely to experience prolonged symptoms than college grads (18.3 percent). “Remember, those who contracted Covid early were often people working in service industries,” Hirschtick points out.
Other patterns are more puzzling. “It’s hard to get a handle on the parameters of Long Covid,” Hirschtick says. “For instance, people who were hospitalized might have prolonged symptoms just because they were hospitalized … But why women? Why Hispanics over other ethnic groups? At this time, it’s just speculation on our parts—and scientists don’t like to speculate.”
“We may actually be classifying a lot of preexisting medical issues under the label of long-haul Covid,” cautions U-M family medicine prof Michael Klinkman. “Remember, many people avoided hospitals and doctors’ offices for as much as two years or met with doctors only online. A lot of underlying illnesses may have gone undiagnosed.”
Hirschtick agrees. “It’s impossible to know if Covid triggered symptoms actually related to other health concerns.”
Klinkman also suspects that respondents may have “stored up” symptoms during their isolation from health care, so sorting out “which symptoms came before, or after, Covid is potentially problematic.” He expects that Long Covid will ultimately be understood as “an alteration or intermittent malfunction in our immune or autoregulatory systems” that interacts with an individual’s genetic makeup and coexisting medical conditions.”
The study’s parameters changed when home tests became available. The state no longer has a complete count of infections. When vaccinations became readily available, the researchers changed their questionnaire and interviews.
“The vaccines made our work harder because they introduced different political opinions and false information into the equation,” Hirschtick says. “More people turned down our requests to participate in the study because they were worried they were being surveyed by political organizations or fundraisers.”
“How worried should people be? A lot more worried than they are,” bioethicist Ezekiel Emanuel told the Guardian in May. “People are behaving as if the pandemic was over. The problem with long Covid is it’s like the problem of hypertension or another illness that is in the future. We inherently discount the future, especially if the things we need to prevent future bad effects from coming are onerous, like wearing a mask.”
People continue to be infected, and reinfected, as new variants evolve and immunity from vaccines and prior exposure wanes. “Covid is not disappearing,” Hirschtick says flatly.
The researchers have at least three more studies planned. Current efforts include reports that break demographics down more specifically, as well as revisiting the earliest patients for a two-year follow-up.
“We have to give more emphasis to the weight of long COVID,” Slocum told Michigan News. “It is going to have a bigger impact than I think people might realize.”