THE search for the mystery person infected with the Brazilian mutation of coronavirus is continuing. 

They are one of six people in England and Scotland who have tested positive for the strain, which is thought to have originated from the city of Manaus.

Five of the six people have been accounted for but experts are still tracing the sixth person, who they said is thought to be in the South East

It has sparked concerns about the outbreak of another strain of Covid, and is the fourth mutation to be found in the past few months. 

New variants emerge regularly and experts are conducting frequent analysis to see which are of concern, and which are not.

So here is what we know about the different strains so far and how they differ from the original Covid-19 infection which arrived last March:

What do we know about coronavirus variants?

There are currently four variants of concern:

  • UK/Kent variant - First detected in the UK and was first sequenced in the UK in September 2020 and called B117
  • UK/Kent variant with E484K mutation - This variant was first detected in Bristol and is the UK variant (B117) with a genetic change also found in both the South African and Brazilian variants, E484K
  • South African variant - First detected in South Africa and first sequenced in the UK in December 2020
  • Brazilian variant - First detected in Japan in travellers from Brazil in January 2021 and has now been detected in the UK

There is also a variant under investigation, a second variant from Brazil, that has been detected in a handful of cases in the UK, but is not causing scientists serious concern.


What is the Brazilian variant?

Experts detected the new variant circulating in December in Manaus, north Brazil.

It is not yet known if the mutation causes more severe Covid-19, but evidence suggests it may be more transmissible.

Scientists are conducting analysis to establish if it has a higher mortality rate or if it affects the vaccines or treatments.

The variant was detected in Brazil and in travellers from Brazil to Japan, and contains a unique constellation of lineage defining mutations.

The P. 1 variant is associated with a surge of cases in Manaus late last year, which led to a severe second wave of Covid-19.

Scientists were concerned because this raised the possibility it is able more easily re-infect patients due to the mutations it carries. But the evidence for this is currently limited.

Like the South African variant, the Brazilian one carries a mutation in the spike protein called E484K, raising concerns that vaccines may not be as effective against it.

What is the UK/Kent variant?

This variant was first detected in Kent in September, and it has been suggested that its spread in December led to a rapid rise in Covid-19 cases before the second national lockdown was announced in England.

It is now thought to be the dominant variant in the UK.

Analysis of the variant, known as B117, suggests it is up to 70 per cent more transmissible than the previous strain that was dominant in the UK.

Despite data suggesting the mutant variant may be more deadly, there is no evidence to indicate existing treatments, such as dexamethasone, will not be effective against it.


A study has suggested that people infected with the UK variant are less likely to report a loss of taste and smell.

The Oxford/AstraZeneca coronavirus vaccine has a similar efficacy against the variant, compared with the original strain of Covid-19 against which it was tested.

Studies also suggest the jab developed by Pfizer and BioNTech is effective against the UK variant of coronavirus.

The Moderna coronavirus vaccine, due to arrive in the UK in the spring, is effective against all emerging mutations of the virus that have been detected to date, according to the company.

What is the UK/Kent variant + E484K mutation?

This variant was first detected in Bristol and a handful of other cases have been identified across the UK.

It carries a genetic change also found in both the South African and Brazilian variants, E484K.

Analysis into this variant is ongoing, and researchers are looking at how vaccines might affect the strain.


What is the South African variant?

About 193 cases of this variant have been detected in the UK.

This variant carries the E484K mutation which experts suggest may be better at evading the human immune response.

The vaccine developed by Pfizer and BioNTech is effective against this variant, according to a study from the US.

However, a separate study found that the Oxford/AstraZeneca jab was not effective at preventing mild illness caused by the more infectious South African mutation.

But the jab will protect against deaths and severe disease amid the spread of the South African variant, according to researchers.

Why do viruses mutate?

There have been many mutations in Sars-CoV-2, the virus that causes Covid-19, since it emerged in 2019.

However, this is to be expected as this virus is what scientists call an RNA virus, like the flu and measles, and these tend to mutate and change.

Mutations usually occur by chance, and the pressure on the virus to evolve is increased by the fact that so many millions of people have now been infected.

Sometimes mutations can lead to weaker versions of a virus, and it could even be that the changes are so small they have little impact on how it behaves.

If new variants spread faster it means they are likely to infect more people, increasing the number of cases.