New variants of coronavirus are constantly being researched and discovered, with some spreading faster than others.
Different strains happen when changes build up in the genetic code of the virus before the new version is then passed from person to person.
Most of the time the changes are so small that they have little impact on the way the virus is spread among the population.
Every so often the deadly bug mutates in a way makes it spread more quickly, sparking concern about the way the virus might behave in response to factors such as a vaccine.
In the UK, a highly transmissible mutation was discovered in Kent which quickly spread and forced the country to go into a full lockdown amid a second wave.
Since then, new mutations around the world have cropped up and posed different threats as we try to deal with the pandemic and vaccination rollout.
Here are the different variants we know about, and the ones that are causing scientists most concern.
What are the new variants of coronavirus?
Genetic evidence suggests the Kent variant emerged in September, 2020, and then circulated at very low levels in the population until mid-November.
The increase in cases linked to the new variant first came to light in December when public health bodies were investigating why infection rates were not falling despite national restrictions.
A cluster linked to this variant was found spreading rapidly into London and Essex and began to move up north to Scotland.
Mutations in the spike protein mean the virus is about about 50% more infectious and spreads more easily between people.
South African variant
The variant first identified in South Africa appears to have emerged around the same time as the variant originating in the UK, according to the UK Government.
As well as containing the mutation to the spike protein it also has a number of other mutations.
Laboratory tests have shown that one mutation, known as E484K, may be able to escape the body’s antibodies to some extent and is therefore of “potential public health concern”.
Two variants of “interest” have been identified in Brazil.
The first variant is currently classified by PHE as a ‘variant under investigation’ and has a small number of mutations but does include E484K. This variant has been detected in 11 countries so far including the UK.
The second variant, also referred to as P.1, was first detected in Manaus, as well as travellers from Brazil arriving in Japan.
As of March 16, a total of 12 cases have been identified in the UK. This variant has been designated a ‘variant of concern’ because it shares some important mutations with the variant first identified in South Africa, such as E484K and N501Y.
It is possible that this variant may respond less well to current vaccines, but more work is needed to understand this.
Two new variants were discovered in January, 2021, one in the Bristol area and one in Liverpool.
The variant discovered in the Bristol area has been classified as a ‘variant of concern’ and is made up of the UK variant with the addition of a mutation known as E484K.
The E484K mutation is present in the South Africa variant, as well as a number of other variants sequenced globally.
Although there is currently no evidence this mutation alone causes more severe illness or greater transmissibility, it is reported to result in weaker neutralisation by antibodies in laboratory experiments.
The variant discovered in the Liverpool area has been classified as a ‘variant under investigation’.
It is made up of the original ‘wild-type’ Covid-19 with the addition of the same E484K mutation.
Again, there is currently no evidence this variant causes more severe illness or greater transmissibility but Public Health England continues to monitor the situation.
In February, 2021 cases of a variant previously detected in other countries, including Nigeria, Denmark and Canada, were reported in the UK.
Initial reports suggested the variant had originated in Nigeria, but subsequent investigations have confirmed it was first detected in the UK.
The new variant has been designated a variant under investigation (VUI).
The small number of cases found are geographically dispersed across England and enhanced contact tracing and genomic sequencing has been undertaken to monitor the situation as it develops.
There is currently no evidence that this set of mutations causes more severe illness or increased transmissibility but Public Health England continues to monitor the situation.
A variant that was of interest to scientists had been seen popping up in travellers who have recently visited Tanzania.
However, there is still little known about this particular strain.
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