Kent Covid variant may be twice as deadly as previous strains, study suggests

10 March 2021, 12:25 | Updated: 14 March 2021, 06:51

The Kent coronavirus variant could be up to twice as deadly as previous strains
The Kent coronavirus variant could be up to twice as deadly as previous strains. Picture: Getty
Nick Hardinges

By Nick Hardinges

The Kent Covid variant may be up to two times more deadly than previous strains of the virus, new research suggests.

Data gathered by epidemiologists at the Universities of Exeter and Bristol found the B117 coronavirus strain is somewhere between 30 per cent and 100 per cent more deadly.

The Kent variant swept across the South East and London at the end of last year, before spreading across the rest of the country and then onto the world.

Researchers said the findings suggest that the variant is linked with a significantly higher mortality rate among adults diagnosed in the community compared with original strains.

Robert Challen, from the University of Exeter, and who is the 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."

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The team examined death rates among people infected with the Kent variant and those who tested positive for other strains.

They discovered that the mutated virus first detected in Kent led to 227 deaths in a sample of 54,906 patients, while the previous strains led to 141 deaths among the same number of closely matched patients.

The B117 strain is more transmissible than the original coronavirus and is believed to have contributed to the rapid increase in cases before new lockdown rules were introduced across the UK.

According to the study, published in the British Medical Journal, the higher transmissibility of the Kent variant meant that more people who would previously have been considered low-risk were admitted to hospital.

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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."

Ellen Brooks-Pollock, from the University of Bristol, said: "It was fortunate the mutation happened in a part of the genome covered by routine testing.

"Future mutations could arise and spread unchecked."

In January a paper from the New And Emerging Respiratory Virus Threats Advisory Group (Nervtag) said there was a "realistic possibility" that the variant was associated with an increased risk of death. However, scientists warned there was a high degree of uncertainty around the data.

Mutations of the virus have raised concerns about whether vaccines would be effective against the new strains, including the now-dominant Kent variant.

But research suggests the Pfizer jab is just as effective against the Kent variant of coronavirus as it was against the original pandemic strain, while other data indicates the Oxford-AstraZeneca jab has a similar efficacy against the variant.