Friday 15 January 2021 12:05 pm

Covid mutations: what we know so far

A Brazilian variant of coronavirus has arrived in Britain, one of the UK’s leading scientists announced this morning.

Speaking during a Science and Media Centre briefing, Professor Wendy Barclay said: “There are two different types of Brazilian variant and one of them has been detected in the UK.”

Transport secretary Grant Shapps this morning insisted that Covid-19 vaccines will work against the new Brazilian coronavirus variant but claimed that travel bans are essential precautions.

South America and Portugal are the latest areas forbidden to enter the UK, after in-bound flights from several southern African countries were last week banned amid fears of the new South African strain.

New variants are emerging that are more infectious than the one that started the pandemic and scientists are urgently studying the threats they pose.

But what do we know so far? How concerned should we be about Covid-19 variants?

The science

All viruses naturally mutate over time. Since Covid-19 was first identified a year ago, thousands of mutations have occurred.

Most of these have little impact but occasionally a virus changes in a way that helps it survive and reproduce.

What are these new variants?

A UK variant first identified in the Southeast of England has become central to the spread of Covid-19 and has reached more than 50 countries across the world. It is now the UK’s dominant strain of coronavirus
A South African strain has arrived in the UK and at least 20 other countries
The UK today activated a widescale travel ban amid fears of two new Brazilian variants. One has already arrived in Britain

How dangerous are they?

There is no evidence so far that coronavirus variants cause more severe disease, but there is concern that the NHS will be overwhelmed by a rapid rise in cases.

Both the UK variant and South African strain are both thought to be more easily transmissible, sparking concern that they could cause an exponential rise in coronavirus cases.

There is little public knowledge about the Brazilian strains at this stage.

Will vaccines still work?

Scientists are confident that vaccines should work against any new variants because they train the body to attack several parts of the virus.

Pfizer last week said its coronavirus vaccine appeared to work against a host of new mutations.

There is, however, concern that they won’t be as effective. Lab studies are underway to check this.

If needs be, vaccines can be tweaked in a matter of weeks or months to better match mutations.

How serious is this?

The real issue here is the likelihood that the UK, South Africa and Brazil variants could be much easier to catch than earlier strains.

All three versions have different spike proteins, the part of the virus which attaches to human cells, making them better at spreading and infecting cells.

The South African strain has more significant changes in the spike protein than the UK variant, making its potential rate of infection problematic.

Scientists are concerned that the South Africa variant may interfere with vaccine effectiveness, as its unique structure may help the virus evade antibodies.