More than 40% of COVID-19 survivors across the world have or had long-term effects after recovering, according to a new study by researchers at the University of Michigan.
Based on the number of infections reported globally by mid-October, that means more than 100 million people have experienced lingering health concerns or are still reporting problems following a COVID infection.
“The health effects of COVID-19 appear to be prolonged and can exert marked stress on the healthcare system,” the researchers wrote.
The research team reviewed 40 studies from 17 countries that looked at patients’ experiences with long COVID, which includes new or persistent symptoms that occur 4 or more weeks after infection. The studies included more than 886,000 patients who tested positive for COVID-19.
Overall, the research team found that global prevalence of long COVID was about 43%. Among patients who needed hospitalization, the prevalence increased to 57%.
The rate was 49% among women and 37% among men, the researchers found.
The rate also varied by location, with the highest reported in Asia at 49%. Europe and North America followed behind at 44% and 30%, respectively.
Based on a World Health Organization estimate of 237 million worldwide COVID-19 infections in mid-October, , more than 100 million people still experience or previously had long-term health consequences from the coronavirus, the researchers calculated.
The most common symptom was fatigue, which affected about 23% of people with lingering issues. Other symptoms, such as shortness of breath, insomnia, joint pain and memory problems, were reported by 13% of people.
The study likely didn’t capture all cases of long COVID, the researchers wrote. What’s more, , some COVID-19 survivors may develop other severe complications and conditions such as multisystem inflammatory syndrome in children, chronic kidney disease, heart disease and chronic fatigue syndrome.
“Further research is necessary to understand the relationship between COVID-19 and these complications and the needs of those living with complications,” they wrote.
The study was published on a preprint server on Tuesday and hasn’t yet been peer-reviewed.