Simply comparing the total number of deaths across countries may provide a misleading representation of the underlying level of transmission of SARS-CoV-2, the virus that causes COVID-19, because of large differences in reported COVID-19 death rates in elderly populations in different countries.
Focus on COVID-19 deaths in under-65s for better insights into infection rates across populations, say researchers
The research, conducted by scientists at the University of Cambridge and the Institut Pasteur, has just been published in the leading journal Nature. It highlights how large COVID-19 outbreaks in European nursing homes, and the potential for missing deaths in some Asian and South American countries, have skewed COVID-19 death data for older age groups, rendering cross-country comparisons of the scale of the pandemic inaccurate.
The researchers say that reporting of deaths from COVID-19 among those under the age of 65 is likely to be far more reliable, and can therefore give clearer insights into the underlying transmission of the virus and enable better comparisons between countries – crucial in guiding government strategies to try to get COVID-19 under control.
“Simply comparing the total number of deaths across countries can be misleading as a representation of the underlying level of transmission of SARS-CoV-2. Most deaths are in older people, but they are the least comparable across countries,” said Megan O’Driscoll, a PhD researcher in the University of Cambridge’s Department of Genetics and first author of the paper.
In countries including the UK, Canada and Sweden, the COVID-19 pandemic has disproportionately affected nursing home residents, who account for over 20% of all reported COVID-19 deaths. The level of SARS-CoV-2 transmission among the general population can be difficult to disentangle from these large outbreaks.
By contrast, some countries in Asia and South America have far fewer reported COVID-19 deaths in older people than expected. One potential explanation for these ‘missing deaths’ is that causes of deaths in elderly populations may be less likely to be investigated and reported as countries struggle to contain the epidemic.
“Nursing homes are enclosed communities of people, and once the virus gets in it can spread quickly resulting in higher levels of infection than in the general population. We’re seeing an excessively large number of deaths from COVID-19 in this older age group, particularly in countries that have many nursing homes,” said Dr Henrik Salje in the University of Cambridge’s Department of Genetics, the senior author of the report.
He added: “It’s not just that residents are older than the general population, they are also generally more frail, so a 70-year old living in a nursing home is often more likely to die of COVID-19 than a 70-year old in the general population. To reduce the overall number of COVID-19 deaths it is vital to protect vulnerable elderly communities.”
Credit: Gerd Altmann from Pixabay
Reproduced courtesy of the University of Cambridge
The University of Cambridge is acknowledged as one of the world's leading higher education and research institutions. The University was instrumental in the formation of the Cambridge Network and its Vice- Chancellor, Professor Stephen Toope, is also the President of the Cambridge Network.