LONDON (Reuters) – A highly infectious variant of COVID-19 that has spread around the world since it was discovered in Britain late last year is between 30% and 100% more deadly than previous dominant variants, researchers said Wednesday.
In a study that compared mortality rates among British people infected with the new variant of SARS-CoV-2 (known as B.1.1.7) against people infected with other variants of the virus that causes COVID-19, the scientists said the new variant the mortality rate was “significantly higher.”
Variant B.1.1.7 was first detected in Britain in September 2020 and has since been found in more than 100 other countries.
It has 23 mutations in its genetic code, a relatively high number, and some of them have made it spread much more easily. Scientists say it is about 40% -70% more transmissible than the previous dominant variants circulating.
In the UK study, published Wednesday in the British Medical Journal, infection with the new variant resulted in 227 deaths in a sample of 54,906 patients with COVID-19, compared with 141 among the same number of patients infected with other variants. .
“Along with its ability to spread rapidly, this makes B.1.1.7 a threat that should be taken seriously,” said Robert Challen, a researcher at the University of Exeter who co-led the research.
Independent experts said the findings of this study add to previous preliminary evidence linking infection with the B.1.1.7 virus variant with a higher risk of dying from COVID-19.
The initial findings of the study were presented to the UK government earlier this year, along with other research, by experts from its advisory group for new or emerging respiratory virus threats, or NERVTAG group.
Lawrence Young, a virologist and professor of molecular oncology at the University of Warwick, said the precise mechanisms behind the high mortality rate of variant B.1.1.7 were not yet clear, but “could be related to levels higher virus replication and increased transmissibility ”.
He warned that the UK variant would likely fuel a recent rise in infections across Europe.
Reports by Kate Kelland; Edited by Pravin Char and Bernadette Baum