The coronavirus variants and which ones scientists are most worried about

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Like any other virus, new variants of coronavirus are constantly being researched and discovered.

Over time, changes can build up in the genetic code of the virus, and these new variants can be passed from person to person. Most of the time the changes are so small that they have little impact. But every so often a virus mutates in a way that benefits it, for example allowing it to spread more quickly, and causes concerns about changes in the way the virus might behave.

In September the Kent mutation of coronavirus was detected and quickly spread around the UK. Since then, new mutations around the world have been identified and pose different threats as we try to deal with the coronavirus pandemic and vaccination rollout.

Here are the different variants we know about, and the ones that are causing scientists most concern.

What do new variants mean for the pandemic?

Doctor Emma Hodcroft, molecular epidemiologist at the University of Bern in Switzerland, is one of the developers behind Next Strain, a project which tracks mutations around the world.

Speaking to BBC Radio Four, she said new variations could have an impact on both how well the vaccines work and the risk of people being re-infected with Covid-19.

She said: “It’s important to keep in mind that mutation is a really normal part of a virus’s life cycle but what has become concerning in the last few months is where those mutations are happening in the virus and the impact they’re having on our epidemic. What we have seen in the last few months is that these mutations aren’t always as neutral as we hoped that they might stay nearer the beginning of the pandemic and they do seem like they can influence things like transmissibility.

“Perhaps one of the most concerning things of all is that they seem like they can cause the virus to be able to re-infect people and even get around, possibly, vaccines. That’s where a lot of the concern is right now, that particularly in countries that have had really big outbreaks, is this a place where the virus can learn to get around that existing immunity which might impact vaccination efforts.”

Find out about cases where you live:

What are the new variants of coronavirus?

Kent variant

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 England was investigating why infection rates in Kent were not falling despite national restrictions. A cluster linked to this variant was found spreading rapidly into London and Essex.

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”.

Brazilian variant

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.

When asked about reports that the Brazilian variant is having a greater impact on younger people, Dr Hodcroft told Radio Four: “This is really new data and it’s hard to know exactly what’s going on here but it’s certainly interesting.

“One possibility is that in a lot of countries of course vaccination efforts have started and targeted strongly the older population. That means that although you might see more infections in young people you might not see more by numbers. Proportionately you’ll start thinking that you’re seeing more young people than older people because they’re vaccinated.

“Similarly, we could be seeing that some variants might also be targeting differences in the immune system that happen as we age. Immune systems are not static over time and it is possible that some variants could be causing more immune reaction in younger people but this is really hypothetical right now. It’s important to remember that we don’t really have good strong data to say for sure whether this could be an impact of vaccination or whether this is a real change that is due to the virus.”

Bristol variant

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.

Liverpoolvariant

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.

Nigeriavariant

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.

Tanzaniavariant

Dr Hodcroft said that a variant that was of interest to scientists had been seen popping up in travellers to Tanzania recently, even though little is currently known about it. She added this can often be the case where facilities to monitor and research virus variants are not as advanced as in other countries.



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Which variant is giving scientists most concern?

Asked which variant was causing most concern, Dr Hodcroft said: “I think right now it’s hard to pick just one but I think the variants that carry the ‘484’ mutation that some people may have heard about. This is a mutation that is found in the variant that was first identified in South Africa and the one first identified in Brazil.

“It’s thought to be related to this ability to re-infect and what makes some vaccines really not work as well. Even though we see this in those two variants of concern, we actually see this mutation popping up in other places as well and in particular in one variant that is sometimes called the New York variant that has spread pretty well in the US in the past few months.

“It’s not the only place you see this mutation and I think that’s one thing that scientists are starting to really think about – is it more about the variant itself or is it more about the mutations and in what combinations they start popping up in, is that what we really need to be worried about seeing those same mutations or combinations of mutations over and over again.”



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