The Kent variant of Covid-19 may be up to twice as deadly as previous strains of coronavirus, scientists have warned.
The mutation, known as B117, swept across the UK at the end of last year before spreading across the world, and is thought to be between 30 and 100 per cent more deadly, according to a new study.
Higher mortality rate
Data, compiled by epidemiologists from the Universities of Exeter and Bristol, has suggested that the variant is associated with a significantly higher mortality rate among adults diagnosed with Covid-19 than with previously circulating strains.
The researchers looked at the death rates among people infected with the new variant, compared with those infected with other coronavirus strains.
They found that the Kent variant led to 227 deaths in a sample of 54,906 patients, compared to 141 among the same number of closely matched patients who had the previous strains.
Robert Challen, from the University of Exeter, lead author of the study, said: “In the community, death from Covid-19 is still a rare event, but the B117 variant raises the risk.
“Coupled with its ability to spread rapidly, this makes B117 a threat that should be taken seriously.”
The Kent variant is also more transmissible than other strains and is thought to have contributed towards the rapid increase in cases before tougher lockdown rules were introduced across the UK.
According to the study, published in the British Medical Journal, the higher transmissibility of the Kent strain meant that more people who would previously have been considered low risk were admitted to hospital with the newer variant.
Leon Danon, from the University of Bristol, senior author of the study, said: “We focused our analysis on cases that occurred between November 2020 and January 2021, when both the old variants and the new variant were present in the UK.
“This meant we were able to maximise the number of ‘matches’ and reduce the impact of other biases. Subsequent analyses have confirmed our results.
“Sars-CoV-2 appears able to mutate quickly, and there is a real concern that other variants will arise with resistance to rapidly rolled out vaccines.
“Monitoring for new variants as they arise, measuring their characteristics and acting appropriately needs to be a key part of the public health response in the future.”
Mutations of the coronavirus have raised concerns about whether vaccines would be effective against the new strains, including the now-dominant Kent strain.
However, research suggests the Pfizer vaccine is just as effective against the Kent variant of Covid-19 as it was against the original pandemic strain, while other data indicates the Oxford/AstraZeneca jab has a similar efficacy against the variant.