Thousands of coronavirus deaths recorded by the Office for National Statistics (ONS) were not due to Covid, new figures show.
On Thursday, the ONS published data comparing Covid deaths in England and Wales to those from influenza and pneumonia up to the end of August.
In order to make the comparison, the body published, for the first time, figures for people who had died "due" to Covid rather than those who had the virus mentioned on their death certificate.
While official figures show that 52,327 people died from coronavirus up to the end of August, 48,168 deaths were "due" to the disease – 4,149 fewer than official records show.
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Early in the pandemic, the World Health Organisation (WHO) warned that even if coronavirus appeared on a death certificate as a "significant condition", the death should not be included in the figures. WHO guidelines say such deaths "are not due to Covid-19 and should not be classified as such".
The new figures back up research from academics at the Centre for Evidence-Based Medicine at Oxford University, who last month found that coronavirus was not the main cause of death for nearly one third of recorded Covid-19 victims in July and August.
The team uncovered the discrepancy after comparing deaths from all causes to the coronavirus figures. Their analysis showed that around 30 per cent of people included in the coronavirus death toll over the summer months had died from other causes.
It means someone who suffered a heart attack, or even died in a road traffic accident, may have been included in the figures if they had also tested positive for coronavirus at some point or if doctors believed the virus may have exacerbated their condition.
Experts at Oxford are concerned that the problem with over-counting will get worse as more people in the population contract coronavirus. They are worried it means thousands more people died at the peak because of the pandemic response rather than because of the virus and have been wrongly included in the Covid-19 statistics.
The new ONS figures also show that Covid was nearly four times deadlier than flu and pneumonia between January and August, with 48,168 deaths, compared with 13,619 for pneumonia and 394 deaths due to influenza.
But the figures also showed that the deaths for flu and pneumonia were nearly 3,500 lower than would normally be expected based on the five-year average, suggesting that some people died of Covid instead (the graphic below shows how flu and Covid-19 compare).
Sarah Caul, the head of mortality analysis at ONS, said: "More than three times as many deaths were recorded between January and August this year where Covid-19 was the underlying cause compared to influenza and pneumonia. The mortality rate for Covid-19 is also significantly higher than influenza and pneumonia rates for both 2020 and the five-year average.
"Since 1959, which is when ONS monthly death records began, the number of deaths due to influenza and pneumonia in the first eight months of every year have been lower than the number of Covid-19 deaths seen so far in 2020."
Professor Rowland Kao, professor of veterinary epidemiology and data science at the University of Edinburgh, said: "The substantially greater number of deaths attributed to Covid-19 does tell us that at the moment, Covid-19 is a greater risk to people than influenza – to some extent this is due to the fact that we have a flu vaccine that is given to individuals at high risk of severe illness/morbidity and mortality, whereas of course for Covid-19 we do not.
"Add to the fact that Covid-19 is new to us, whereas we would expect some immunity between years of seasonal flu – highly variable, depending on the level of antigenic drift. Thus these data are entirely consistent with what we would expect."
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