The prevalence of so-called “long-COVID” in the UK is less common than previously estimated, official data suggests.
According to an update published by the Office for National Statistics (ONS) on Thursday, only 3 percent of people who tested positive for the CCP (Chinese Communist Party) virus had symptoms lasting more than 12 weeks, “substantially lower” than the ONS’ previous estimation published in April (13.7 percent).
The ONS said the new analysis benefited from both longer follow-up time and updated statistical methodology.
Researchers analysed data between April 26, 2020, and Aug. 1 this year from more than 20,000 Coronavirus Infection Survey participants who had a positive PCR test for the CCP virus, and who can be matched to a control participant.
Among the control group, who didn’t test positive for the CCP virus, 0.5 percent had symptoms lasting 12 weeks or longer.
The 12 symptoms that ONS asked about were fever, headache, muscle ache, weakness/tiredness, nausea/vomiting, abdominal pain, diarrhoea, sore throat, cough, shortness of breath, loss of taste, and loss of smell.
Due to the observational nature of the study, it’s impossible to know for certain what were the causes of the symptoms, the ONS said.
While including non-continuous symptoms, 5 percent of the COVID group had symptoms at a point in time between 12–16 weeks after infection. In the control group, 3.4 percent of the participants had these symptoms, “demonstrating the relative commonness of these symptoms in the population at any given time,” the ONS said.
The ONS stressed that there’s currently no universally agreed definition of long COVID, and different studies are using different methods in their research into the phenomenon.
To include other known COVID symptoms outside of the 12 specified symptoms, researchers also asked participants to self-report long COVID.
Approximately 11.7 percent of participants with COVID-19 would describe themselves as having long COVID 12 weeks after infection, and 7.5 percent said they had long COVID that resulted in limitation to day-to-day activities.
“Irrespective of the approach to measurement, post-acute symptom prevalence was highest in females, adults aged 50 to 69 years, people with a pre-existing health condition, and those with signs of high viral load at the time of infection,” the ONS added.