Beta coronavirus variant: What is the risk?

Fully jabbed travellers arriving in the UK from France have to quarantine, because of the Beta variant.

The government is concerned jabs may not work as well against the variant.

French authorities say most cases are from the overseas territories of La Reunion and Mayotte, rather than mainland France.

Beta, also known as 501.V2 or B.1.351, has some significant genetic changes that experts are studying. It was first identified in South Africa.

All viruses, including the one that causes Covid-19, constantly mutate into new versions or variants.

These tiny genetic changes happen as the virus makes new copies of itself to spread and thrive.

Most are inconsequential, and a few can even be harmful to the virus's survival, but some variants can make the virus more infectious or threatening to the host - humans.

Some of the changes Beta has undergone involve the virus's spike protein - the part that gains the virus entry into human cells. It is also the bit that vaccines are designed around, which is why experts are concerned about these particular mutations.

Beta, along with a few other variants of coronavirus, such as Delta and Alpha, have been labelled "variants of concern". These have some worrying changes experts want to keep a very close eye on.

Beta carries a mutation, called N501Y, which appears to make it more contagious or easy to spread.

Another mutation, called E484K, could help the virus dodge a person's immune system, and may affect how well vaccines work.

There is no evidence that the South Africa variant causes more serious illness for the vast majority of people.

As with the original version, the risk is still highest for elderly people and those with significant underlying health conditions.

Vaccines are designed around original Covid, rather than new variants.

There is some evidence they are less effective at stopping Beta infections.

But experts say they should still work to stop severe illness.

Even in the worst case scenario, vaccines can be redesigned and tweaked to provide a better match in a matter or weeks or months, if necessary.

Some of the other Covid vaccines are also being updated.

The Beta variant has been identified in more than 50 countries around the world.

So far, the UK has recorded just over 1,000 cases of Beta. That's a tiny fraction of all Covid cases. Another variant, called Delta, currently makes up more than 99% of Covid seen in the UK.

When it was first identified in the UK, the government recommended surge testing in the community in some regions to help stop the spread.

A system of foreign travel restrictions has also been introduced to minimise the chance of UK travellers spreading Beta as well as other variants of concern.

They will also have to take two PCR tests to ensure they are not infectious.