New data suggests that real numbers may be much smaller than claimed
New evidence suggests that the extent of the “Long Covid” phenomenon may have been dramatically exaggerated.
The risks of Long Covid was a central argument in favour of draconian restrictions during the pandemic and, according to official figures, the condition remains extremely widespread. The Center for Disease Control and Prevention in the United States states that nearly one in five American adults who have had Covid-19 are experiencing Long Covid. Meanwhile, self-reported survey data from the UK indicates that there are 1.8 million people — 2.8% of the whole population — currently living with the condition.
But new data is complicating this picture, and indicating that many of the self-reported Long Covid cases may be incorrectly recorded.
A paper published on 14th August by the Institute of Child Health at Great Ormond Street, currently undergoing peer review, found that teenagers whose parents have had Long Covid symptoms are more likely to report suffering Long Covid symptoms themselves. Notably, this association was present in teenagers regardless of whether they tested positive or negative for Covid-19 at the outset of the trial period.
Researchers followed a cohort of 12,788 11-17 year-olds with confirmed positive Covid-19 PCR tests, and compared them to a control group matched by age, sex and geographical area with negative PCR tests. 33.3% of teenagers with “Long Covid parents” reported symptoms of the illness; by contrast, 22.6% of teenagers whose parents didn’t have Long Covid reported symptoms that could match the condition.
Lead author of the study and Professor of Pediatric Infectious Diseases and Vaccinology at St George’s University of London, Dr Shamez Ladhani, told UnHerd that, among other potential factors, “there is a component where lots of parents are anxious [about Long Covid], and that anxiety can be passed to their children”.
The study raises doubt over whether we can always confidently assert the presence of Long Covid, especially in children. The problem, according to Dr Ladhani, is that the symptoms — which include fatigue, abdominal pain and headaches — are too broad and common to assert a connection.
“The biggest damage we’ve done is to open up a pandora’s box and start attributing every symptom to Long Covid. There is a small minority of children who do develop serious complications after Covid, but this proportion is much lower than reported rates, likely less than 1%.”
Other recent data has come to a similar conclusion. A study published in Nature magazine on 25th July found at least one Long Covid symptom occurred in 5.4% of patients who had tested positive for the virus, compared to 4.3% of patients who had never tested positive for the virus.
This same study also supports emerging theories about possible psychological drivers behind people self-diagnosing with Long Covid. It found anxiety and depression to be comorbidities highly associated with an increased risk of reporting such symptoms. Using the World Health Organisation’s definition of Long Covid, researchers found 13.5% of those who suffered from anxiety prior contracting Covid to have self-reported symptoms, compared to 7.7% of the overall sample. Similarly, 13.4% of people already suffering from depression self-reported Long Covid symptoms, compared to the same sample. Anxiety and depression were among the most common comorbidities of apparent Long Covid.
The most recent US Census Bureau Household Pulse survey uncovered another confounding association: transgender people are significantly more likely to report suffering from Long Covid symptoms than the general population. It estimated that 47% of transgender adults who have had Covid claim they are suffering from Long Covid symptoms, compared to 39% of women and 26% of men who say they are experiencing symptoms.
With so many cases being claimed, the risk is that genuine cases are obscured. As Dr Ladhani told UnHerd, “we cannot identify the actual risk because real cases are getting buried in the noise.”