TOPLINE The number of coronavirus patients still experiencing symptoms weeks and months after infection is far lower than previously feared, according to new research by the U.K’s statistics office published this week, as experts warn the lack of clear symptoms for long Covid, which can last for months after infection, may be overestimating its prevalence.
KEY FACTS
Some 3% of people with Covid-19 had continuous symptoms three months after the initial infection, according to a new analysis by the U.K. Office for National Statistics, down from an estimated 14% in April.
The estimates varied significantly depending on how long Covid was assessed, the researchers noted, as 5% of people reported experiencing Covid symptoms up to 16 weeks after infection, but a greater 12% of people saying they were experiencing long Covid.
However, it’s possible normal bouts of ill health could be mistaken for long Covid—which has symptoms like fever, muscle aches, tiredness, diarrhoea and cough—the study found, making long Covid seem more common than it actually is.
Some 0.5% of people in the study’s control group, i.e. those who did not have Covid, also reported ongoing symptoms similar to those associated with long Covid and 3.4% reported experiencing any symptom up to 16 weeks after infection.
The findings are in line with a review of research covering around 19,000 children and teens around the world published in the Pediatric Infectious Disease Journal, which found a similar proportion of commonly reported symptoms in those infected with Covid-19 and those who were not.
Children that do go on to experience lingering symptoms rarely do so for more than 12 weeks, the review found.
KEY BACKGROUND
It’s not clear why some people who get Covid-19 continue to have symptoms for weeks or months after their initial infection and there is a lot about the condition we do not know. Researchers say the lack of a consistent framework with which to analyze or identify long Covid makes this harder and a lot is being learned as more time passes from earlier waves of the pandemic. The list of possible symptoms for long Covid is long—one study identifies over 200—and affects the entire body. Vaccines slash the risks of developing long Covid, studies have found, both by lowering the risks of catching Covid-19 and protecting against long Covid in breakthrough infections.
BIG NUMBER
1.23 million. That’s roughly how many U.S. residents could be suffering from long Covid, using the 3% estimate calculated in the U.K. and Johns Hopkins University figures highlighting 41 million American Covid-19 cases that did not result in death. The figure, as the ONS researchers note, is far from authoritative and more research will be required to understand the condition.
How common is long COVID? That depends on how you measure it (ONS)
By Robert Hart, Forbes Staff