UK covid-19 variant (B.1.1.7)
The Kent variant of coronavirus was first seen in the South East of England
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First sequenced in September 2020, the UK variant of coronavirus emerged in southeast England, and is commonly known as B.1.1.7. It is around 1.5 times more transmissible than other covid variants, and the risk of dying is around 1.6 times higher.
The UK and Ireland were forced to impose new lockdowns after surges in covid-19 cases at least partly due to B.1.1.7, and there are fears it will cause a new wave of infections around the world. It has already been found in over 50 countries, with the highest number of cases outside the United Kingdom reported in Denmark, the US, France and Belgium. These numbers reflect how much sequencing countries do.
B.1.1.7 was formally identified as a variant of concern by Public Health England in December 2020 under the name Variant of Concern 202012/01, and is also referred to as the Kent variant.
There are 17 mutations from the original SARS-CoV-2 virus first discovered in Wuhan, China, eight of which change the shape of the outer spike protein. This may allow the virus to bind to receptors on human cells more easily and thus get into cells more easily, allowing the virus to replicate in the upper airways much faster. However, we do not know for sure why it shows such increased transmission.
It is not known how the variant first mutated, but there is speculation that it could have evolved in the body of a person with a weakened immune system, which was not strong enough to kill off the virus, but did force it to evolve and mutate.
Symptoms of the UK variant are largely the same as those previously linked with covid-19, such as persistent cough and fever. However, fewer people reported symptoms of anosmia, a loss or change in sense of taste or smell, in January when B.1.1.7 accounted for about 86 per cent of infections, than in November to December when it was just 16 per cent.
Studies suggest the new UK variant is slightly deadlier than older variants, but with better treatments available the risk of death may still be lower than when the pandemic started.
Existing vaccines may be slightly less effective against B.1.1.7. For instance, the Oxford/AstraZeneca vaccine appears to about 74 per cent effective at preventing symptomatic infections due to B.1.1.7, compared with 85 per cent for other variants.
In the UK, a few B.1.1.7 viruses now also have an additional mutation called E484K can help B.1.1.7 viruses evade antibodies. This is the same mutation that helps the South African variant and the P.1 variant in Brazil evade antibodies to other coronavirus variants.
These B.1.1.7 variants with the E484K mutation might therefore be both a faster-spreading virus and better at evading immunity. However, so far only 21 cases have been detected and the UK is trying to prevent its spread by increasing testing and tracing.