The health secretary for England, Matt Hancock, said authorities across the UK would have to come down hard on this variant.

Around 80,000 people in England will be offered urgent tests.

Now door to door testing will be carried out in the affected areas.

Certain post codes in London, the West Midlands Heart Future, Kent, Surrey on DMA Merseyside.

Mr Hancock urged people in these postcode areas to stay at home unless they absolutely have to leave to get a covert test.

Health officials are confident that the current vaccines will be effective against the South African strain, but probably not as effective as they are against the others.

Our health editor, Hugh Pym, has the latest details.

New mobile testing units have moved into some communities in England, part of a drive to track the spread of the South African variant of the virus.

All this after a handful of cases were discovered, which could not be linked to arrivals from South Africa or other countries.

around 80 0 people aged 16 and over in eight areas, most in the southeast of England and one in the West Midlands have been asked to take tests regardless of symptoms.

Positive cases will be analyzed to see if they're caused by the variant.

If you live in one of these post codes, where we're sending in enhanced testing than it is imperative that you stay at home on that, you get a test even if you don't have symptoms.

This is so important so that we can break the chains of the transmission off this new variant, and we've got to bring this virus to heal.

How confident are you that the existing vaccines in use will be effective against the South African variant?

So three off the vaccines that are that have been used to date in trials have shown that they've been effective against South African variant.

We expect all other vaccines to have a similar level of effectiveness, particularly in reducing hospitalization and death.

There's speculation the vaccines might have to be adjusted to cope with new variants.

It is unlikely that people would have to start again, much more likely that it would be a booster shot a bit like the annual flu vaccine.

Local councils like Woking have been sent home testing kits.

Officials have been preparing to distribute them as fast as possible.

The aim now is to contact as many households as they can.

What we're doing is mobilizing over 100 volunteers to go out, knock on residents doors in a defined geographical area with letters and testing kits with the request that they carry out a test themselves on.

Then we'll come and collect it.

So this is about identifying how far the South African variants has spread within the community in the areas being targeted, like hand well In West London, local people have been urged to take extra precautions with a call for them to minimize social contact as well as getting a Testa's soon as they can.

Officials say the variant doesn't make people sicker than the original strain, but it can spread fast, and that's what they want to stop.

Hugh Pym, BBC News.

We'll talk to you in just a moment.

Let's have a look at the latest government figures.

They show there were 18,607 new coronavirus infections recorded in the latest 24 hour period, which means that on average, the number of new cases reported per day in the past week is 23,732.

Number of people in hospital has fallen slightly down to 34,783 406 deaths were reported as people who died within 28 days off a positive covert tests.

And that figure is always somewhat lower after the weekend.

On average, in the past week, there were 1148 deaths announced every day, taking the total so far across the UK to 106,564.

Let's have a look at the vaccine roll out.

This shows that 319,000 and 38 people have had their first dose off one of the three approved co vid 19 vaccines in the latest 24 hour period on That means in total that nearly 9.3 million people in the UK have had their first vaccination.

So as I mentioned that he was with me and when we look at the challenge posed by the South African variant.

What's your understanding of the scale of that?

We're here to look at it one way.

They're just 11 cases where there are no known links to international travel, 105 in all.

Officials say it doesn't make patients sicker than they would have been with the original strain of the virus.

And as we've been hearing public health, England certainly think that the vaccines will be effective enough, if not quite as effective as they were with that first strain.

But it is mawr transmissible.

That means it spreads more rapidly a bit like that original UK variant, which emerged in Kent back at the turn of last year or towards the end of last year on That's what they really are worried about, why they are putting people into these local communities, flooding it with testing capability in Mount Hancocks.

Words to come down very hard on it to stop it spreading any further.

Because, of course, across the UK cases of falling 30% week on week hospital admissions, air coming down 20% week on week, they don't want this picking up again.

Of course, at a time when ministers and officials are looking ahead to the possibility of easing restrictions, Okay, you once again, many thanks.