Public health experts are divided over how many people are getting long COVID-19, a potentially debilitating condition that comes after a patient has recovered from the coronavirus.
Ill effects from the condition can include fatigue, pain, neurological issues and even changes in mental health.
Initially, public health officials believed that only a small minority of people would suffer from long-term COVID-19. But some studies now indicate a majority of those infected with the coronavirus are experiencing long COVID-19 symptoms.
Still, estimates on the numbers of people with long COVID are all over the map.
Researchers from the Penn State College of Medicine found that more than half of COVID-19 survivors had long COVID-19.
Another study from the University of Arizona found that about 2 out of 3 people who experienced mild or moderate cases of coronavirus had long-lasting symptoms.
Other reports have been more conservative, estimating anywhere between 10 to 30 percent of those infected develop long-term symptoms. Those who experience ongoing symptoms from long COVID-19 have sometimes come to be known as COVID-19 long haulers.
It’s generally believed that people who developed severe cases of COVID-19 are more likely to have long COVID-19, but even those who had asymptomatic cases have reported lingering after-effects months after testing negative.
One problem in figuring out how many people get long COVID-19 is defining it.
Apart from the wide range of symptoms, there is still debate over when a person is considered to have long COVID-19. Some health care authorities consider a patient to have the condition if symptoms persist after three to six weeks, while other think it should be considered on a longer basis.
Jim Heath, president and professor at the Institute for Systems Biology, is leading the Pacific Northwest consortium researching long COVID-19 as part of the National Institute of Health’s (NIH) RECOVER initiative, which is looking into the post-COVID-19 condition and potential ways of preventing and treating it.
Heath told The Hill that if one definition of COVID-19 was being used — one in which symptoms lingered about four to six weeks after infection — then roughly half of those infected would be considered to have long COVID-19.
“But if you look at like six months out, which is for people that are really going to have to live with something, it’s probably more like 15 percent, something like that. I don’t know if we have really firm numbers on that yet,” Heath said.
According to Heath, an estimate of 15 to 20 percent of coronavirus survivors experiencing long COVID-19 after six months was a reasonable “educated guess” and he added that there was evidence to support that rate of occurrence.
When reached for comment by The Hill, the NIH said initial studies had found that at least half of COVID-19 patients who were hospitalized reported “persistent weakness or fatigue” months after their recovery.
Studies on the prevalence of long COVID-19 have been “relatively few,” according to the NIH, and they have all focused on people who had symptomatic cases of COVID-19.
Heath reiterated that most people will not get long COVID-19, at least if you consider the condition to be something that will last six months post infection. In comparison, around 15 percent of people who contract Lyme Disease, a bacterial infection spread through ticks, will experience effects that go beyond six months.
What makes long COVID-19 unique is its occurrence in those who had mild cases, Heath said.
The NIH said numerous observational studies in both children and adults are being conducted to find potential treatments for long haulers. The agency has requested applications for new clinical to launch this summer to test potential ways of preventing and treating long COVID-19.
“In contrast to the wealth of prior knowledge that led to the vaccines for Sars-CoV-2 and a host of other viruses, there is much less known about what causes persistent symptoms following infectious diseases or how to best treat them. As a consequence, there is more knowledge needed to fuel the scientific advances to come,” the NIH said.