The coronavirus, which first arrived in the UK a little over a year ago, continues to mutate – with a number of variants now floating around the country.
The original virus that causes Covid-19 is believed to have emerged in Wuhan, China. World Health Organization experts have just completed a trip to the region to investigate their origins.
Strict new travel rules were introduced in the UK when cases of a mutant strain of virus from South Africa were found here.
Further travel restrictions came when a contamination was found from Brazil – with the strictest border rules that went into effect on Monday.
At the same time, the UK is seeing native mutations of the virus in the UK – with new strains in Kent, Bristol and Liverpool.
Experts said this week that the Kent variety, which is 70 percent more transmissible, is likely to become the dominant strain around the world.
There are “variants of concern” and “variants studied”.
SARS-CoV-2 variants are used for formal testing if they have epidemiological, immunological or pathogenic properties.
At this point, they are called Variant Under Investigation (VUI) with a year, month, and number. After a risk assessment with the responsible committee of experts, they can be referred to as Variant of Concern (VOC).
This is what we know about all of the strains found in the UK so far
There are currently four worrying variants:
Kent variant : First discovered in the UK and first sequenced in the UK in September 2020 and named B117.
Bristol variant + E484K mutation : This variant was first detected in Bristol and is the British variant (B117) with a genetic modification found in both the South African and Brazilian variants E484K. There were 22 cases.
South African variant : First discovered in South Africa and sequenced for the first time in the UK in December 2020.
Brazilian variant : First discovered in Japan by travelers from Brazil in January 2021 and not discovered in Great Britain.
And two variants are being examined
Brazilian variant 2: First discovered in Brazil, 28 cases have been confirmed in England and one in Scotland. It was first discovered in November.
Liverpool variant: 43 cases have been identified in Liverpool and the North West. It shares the same E484K mutation as the Kent and SA variants.
UK / Kent variant
This variant was first spotted in Kent in September, and its spread has been suggested to cause a rapid surge in Covid-19 cases in December, before the second national lockdown in England was announced.
It is now believed to be the dominant variant in the UK.
Analysis of the variant known as B117 suggests that it is up to 70% more transmissible than the previous strain prevalent in the UK.
While data suggests that the mutated variant could be more deadly, there is no evidence that existing treatments like dexamethasone are not effective against it.
One study found that people infected with the British variant were less likely to report loss of taste and smell.
The Oxford / AstraZeneca coronavirus vaccine has similar efficacy across the variant when compared to the original strain of Covid-19 it was tested against.
Studies also suggest that the shock developed by Pfizer and BioNTech against the UK variant of the coronavirus is effective.
The Moderna coronavirus vaccine, expected to arrive in the UK this spring, is effective against any newly discovered mutations in the virus that have been detected so far, according to the company.
However, researchers have discovered strains of the British virus that have developed a mutation, E484K, found in the South African and Brazilian variants.
Studies show that this mutation may be better able to escape the body’s immune response, making vaccines less effective.
UK / Kent variant + E484K mutation
This variant was first discovered in Bristol, and a handful of other cases have been identified across the UK.
It carries a genetic modification that can be found in both the South African and Brazilian variants E484K.
Analysis of this variant is still ongoing, and researchers are studying how vaccines could affect the strain.
South African variant
Around 170 cases of this variant have been found in the UK.
This variant carries the E484K mutation, which experts suspect may better bypass the human immune response.
The vaccine developed by Pfizer and BioNTech is effective against this variant, according to a study from the USA.
However, a separate study found that the Oxford / AstraZeneca surge was not effective in preventing the mild illness caused by the more infectious South African mutation.
However, according to researchers, the shock will protect against deaths and serious illness as the South African variant spreads.
England’s Deputy Chief Medical Officer said this burden is unlikely to dominate the UK for the coming months.
No cases of the affected Brazilian variant were found in the UK.
Experts discovered the new variant, which was in circulation in Manaus, northern Brazil, in December.
It’s not yet known if the mutation causes more severe Covid-19, but there is evidence that it may be more transmissible.
Scientists are doing analysis to see if it has a higher death rate or if it is affecting vaccines or treatments.
The variant was found in Brazil and in travelers from Brazil to Japan and contains a unique constellation of line-defining mutations.
Like the South African variant, the Brazilian one carries a mutation in the spike protein E484K, raising concerns that vaccines may not be as effective against this protein.
The other variant from Brazil was discovered in the UK, but experts say this is nothing to worry about.
Why do viruses mutate?
There have been many mutations in Sars-CoV-2, the virus that has caused Covid-19 since it emerged in 2019, some more significant than others.
However, this is to be expected because this virus is an RNA virus like flu and measles that has a tendency to mutate and change.
Mutations usually occur randomly, and the pressure on the virus to develop is increased by the fact that so many millions are now infected.
Sometimes mutations can result in weaker versions of a virus, and the changes may even be so small that they have little effect on behavior.
If new variants spread faster, it means they are likely to infect more people and increase the number of cases.
Viruses evolve to survive – mutations are a simple mistake that gives the virus a chance to keep infecting people.
What is a mutation?
In simple terms, a virus delivers a series of instructions to a cell in the body, and the cell follows those instructions to create more new viruses.
The instructions are replicated so that each newly created virus receives a single copy of the copied code.
Sometimes there is a mistake in the instructions and when this virus infects a new cell it either fails or the virus continues to replicate the mutated code.