More than half of people suffering from long Covid may not have the condition and may just be suffering from normal bouts of ill health, research from the Office for National Statistics (ONS) suggests.
The ONS surveyed nearly 27,000 people, who tested positive for Covid, in the UK Coronavirus Infection Survey and used three different methods to estimate the prevalence of long Covid.
In one analysis, they found that five per cent reported at least one symptom 12 to 16 weeks after their infection.
However, the study also found that 3.4 per cent of people who had not been diagnosed with Covid also reported the same long Covid symptoms.
Kevin McConway, emeritus professor of applied statistics at The Open University, said: “That’s not all that much less than the 5.0 per cent for the infected people, which does show that having one or more of these symptoms isn’t uncommon regardless of Covid-19.”
Normal ailments or long Covid?
Long Covid symptoms are fever, headache, muscle ache, weakness/tiredness, nausea/vomiting, abdominal pain, diarrhoea, sore throat, cough, shortness of breath, loss of taste and loss of smell.
However, the ONS said that such conditions were experienced regularly within the general population.
A second analysis found that just three per cent of people reported continuous symptoms for at least 12 weeks after an infection, compared to 0.5 per cent of the control population.
However, in a third analysis, when the group was asked to self-identify as suffering from long Covid, 11.7 per cent said that they believed they had the condition, with 7.5 per cent saying the condition limited their day-to-day activities.
When confined to only people who had suffered symptomatic Covid, the number saying they suffered from the condition rose to 17.7 per cent.
Watch: What is long COVID?
Long-term after effects
Previous studies have suggested up to a fifth of people catching Covid will suffer from long-term after-effects.
The ONS said that depending on which measure was used, the data showed between three and 11.7 per cent of Covid cases still had symptoms 12 weeks after an infection.
Commenting on the findings, Dr Michael Absoud, honorary reader at the department of women and children’s health at King’s College London, said: “The ONS are to be congratulated for engaging with clinicians and scientists to review their methodology and provide updated estimates on post-Covid symptoms.
“The ONS first published the approach in April 2021, and reported a 12-week prevalence of long Covid in 14 per cent. This has now been revised down to 3 per cent in the latest estimate.
“The significant fall in the prevalence estimate is due to different interpretations of when symptoms come to an end, and also better long-term follow-up for symptoms beyond the 12-week point.”
Long Covid still remains a problem
However, Prof McConway said that even with low prevalence, Covid cases were currently so high in the community that long Covid was still a problem.
“It’s reassuring, of course, that most people who are infected don’t go on to develop long Covid. But in absolute numbers, really a lot of people will be developing a quite long-term illness,” he added.
“For the week 14-20 August, the total estimate for the whole of the UK community population is that there were 526,000 new infections that week. If three per cent of those new infections result in long Covid, that’s getting on for 16,000 new long Covid cases just from infection that week.
“And if the highest figure from the new ONS bulletin, 12 per cent of the infections, result in long Covid, that would be over 60,000 new long Covid cases just from a week’s worth of infections across the UK.”
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