Concerns have risen over a new Covid-19 variant which has been identified in Brazil, raising questions on if it could cause more severe disease, or be immune to current vaccines.

The British government in a bid to protect its citizens from the new variant has closed its borders to travellers from South America, Portugal and neighbouring island states like Carpe Verde.

Safeguarding Minister Victoria Atkins said that the government was keeping coronavirus restrictions under “constant review”.

Here is what you need to know about the new Brazil Covid mutation:

The Brazilian variant has three key mutations in the spike receptor-binding domain (RBD) that largely mirror some of the mutations experts are worried about in the South African variant.

The coronavirus RBD is one of the main targets for our immune defences and also the region targeted by vaccines.

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

It is not yet known if the mutation causes more severe Covid-19.

Like the South African variant, the Brazilian one carries a mutation in the spike protein called E484K, which is not present in the UK strain.

The E484K mutation has been shown to reduce antibody recognition, helping the virus to bypass immune protection provided by prior infection or vaccination.

Data also suggests the Brazilian variant has been detected in Japan.

Scientists analysing the Brazilian variant say the mutations it shares with the South African variant seem to be associated with a rapid increase in cases in locations where previous attack rates are thought to be very high.

They say it is therefore essential to rapidly investigate whether there is an increased rate of re-infection in previously exposed individuals.

Can the already developed Vaccine be effective against the new variant?

Experts say it is still too early to tell whether the current vaccines will be effective against the Brazilian and South African variants, while it is thought they will work against the UK variant.

However, research is currently in progress to assess this.

Nonetheless, a new coronavirus jab could be manufactured within just 30 to 40 days if a variant of the virus is found to be less responsive to the vaccines available, according to Nadhim Zahawi, Vaccine Development Minister.

He told the Commons Science and Technology Committee that measures have been put in place to produce the “next iteration” of jabs if needed.

Experts say the new vaccines are essentially like “emails that we send to the immune system and are very easy to tweak.”

If the virus has changed, that email simply has to be edited, with a word or two changed, and in a number of weeks a new vaccine will be ready that can better target the new strain.

What is being done to assess the risk posed by the Brazil variant?

Dr Susan Hopkins, deputy director of the National Infection Service of Public Health England (PHE) said PHE experts were looking at the variant and need to grow the virus in the UK in order to perform laboratory experiments.

Experts need to understand the biology of new strains, as well as understanding mutations. The key thing they are currently looking at is whether the mutations mean the virus escapes the immune response. A lot is still unknown about the variant, and analysis is ongoing.

Why do viruses mutate?

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

However, this is to be expected as this virus is 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.

However, the UK variant is more transmissible, and it is thought the same may be true of the Brazilian variant.

Viruses evolve in order to survive – mutations are a simple mistake that gives the virus a chance to keep infecting people.