The U.K. coronavirus variant known as B.1.1.7 is not only more transmissible, but also more deadly than other coronavirus variants, according to a new study published today.

B.1.1.7 was first identified in the U.K. last fall and by December it was detected in several other countries including the U.S. The variant is known to be substantially more transmissible than other SARS-CoV2 coronavirus lineages and quickly took over as the dominant variant in the U.K., late last year, sparking off a damaging and deadly second wave which leaves the U.K. currently second in the world for the most Covid-19 deaths per 100,000 people.

Scientists had suspected that B.1.1.7 might be more deadly, as well as more transmissible following spectacularly high numbers of Covid-19 deaths in the U.K. during the second wave this winter, which saw the U.K’s worst daily death total in January claim over 1,800 lives. But, the new study published in the journal Nature, led by researchers at the London School of Hygiene and Tropical Medicine all but confirms that this correlation is genuine.

The study looked at viral genetics data from almost 5,000 people in the U.K. who died from Covid-19, with two-thirds of those being confirmed to have the B.1.1.7 variant. It found that people who were infected with B.1.1.7 had a 55% higher risk of dying within 28 days of being tested positive for Covid-19.

“England has suffered an enormous toll from B.1.1.7 in the last few months, with 42,000 COVID-19 deaths in January and February 2021 alone,” said Nick Davies, PhD, lead author from LSHTM’s Centre for the Mathematical Modelling of Infectious Diseases. “In spite of substantial advances in COVID-19 treatment, we have already seen more deaths in 2021 than we did over the first eight months of the pandemic in 2020. Our work helps to explain why,” Davies added.

The new work follows another study from the U.K. published last week, which showed that people who tested positive for B.1.1.7 in a community setting were also more likely to die within 28 days of a positive test than those with other variants.

The U.K.’s second wave is receding now in both cases and death numbers and many there will be hoping that the high numbers of people who have received at least one dose of a Covid-19 vaccine there will protect against a similarly damaging third wave. However, the situation is more concerning in several other countries, including France, Germany, Italy and Poland who are now being hit hard by B.1.1.7-fuelled third waves and are not doing nearly as well with vaccine rollouts.

“The B.1.1.7 variant is more transmissible, and our research provides strong evidence that is also causes more severe illness. This should serve as a warning to other countries that they need to remain vigilant against B.1.1.7, which has already spread to over 90 countries worldwide,” said Davies.

The good news, however, is that Covid-19 vaccines appear to be highly effective against the B.1.1.7 variant, with many countries including the U.S. hoping that fast vaccine rollouts will curb its spread.

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