SCIENTISTS say the mutant variant of Covid causing international alarm has now been detected in Israel.

Israel health officials said a patient tested positive for B.1.1.529 after returning from Malawi, increasing fears that the variant may already be rampant across continental Africa. Israel has two other cases.

The news came as other European countries followed the UK's lead in banning flights from Africa.

A travel ban is to be imposed on six African nations  today due to rising concerns over the new variant of the virus which officials have dubbed “the worst one we’ve seen so far”.

UK officials sounded the alarm on Thursday night over the B.1.1.529 variant, which has the potential to evade immunity built up by vaccination or prior infection.

Health Secretary Sajid Javid said the new variant identified in South Africa “may be more transmissible” than the Delta strain and “the vaccines that we currently have may be less effective”.

He said that flights from South Africa, Namibia, Lesotho, Botswana, Eswatini and Zimbabwe will be suspended from midday Friday and all six countries will be added to the red list.

While no cases have been found in Britain, officials raised concern over a rapid rise in cases in South Africa.

Anyone who has arrived from the country in the last 10 days will be invited to come forward and take a test by the UK Health Security Agency.

At the moment, around 500 and 700 people are travelling to the UK from South Africa each day, but it is expected this figure could increase as the festive period begins.

Mr Javid said: “The early indication we have of this variant is it may be more transmissible than the Delta variant and the vaccines that we currently have may be less effective against it.

“Now to be clear, we have not detected any of this new variant in the UK at this point in time.

“But we’ve always been clear that we will take action to protect the progress that we have made.

“So what we will be doing is from midday tomorrow we will be suspending all flights from six, southern African countries and we will add in those countries to the travel red list. Those countries are South Africa, Namibia, Lesotho, Eswatini, Zimbabwe and Botswana. We will be requiring anyone that arrives from those countries from 4am on Sunday to quarantine in hotels.

“If anyone arrives before then they should self-isolate at home and take a PCR test on day two and day eight. If anyone has arrived from any of those countries over the last 10 days, we would ask them to take PCR tests.”

Mr Javid added: “Our scientists are deeply concerned about this variant. I’m concerned, of course, that’s one of the reasons we have taken this action today.”

Asked what the situation would mean for the UK over the coming weeks, with Christmas approaching, Mr Javid said: “We’ve got plans in place, as people know, for the spread of this infection here in the UK and we have contingency plans – the so-called Plan B.

“But today’s announcement, this is about a new variant from South Africa – it’s been detected in South Africa and Botswana – and this is about being cautious and taking action and trying to protect, as best we can, our borders.”

He said that more work was needed to understand how concerning the variant is, adding: “From what we do know there’s a significant number of mutations, perhaps double the number of mutations that we have seen in the Delta variant.

“That would suggest that it may well be more transmissible and the current vaccines that we have may well be less effective.”

The variant has not yet been given the title “variant of concern” in the UK, but one senior UK Health Security Agency (UKHSA) expert said: “This is the worst variant we have seen so far.”

Only 59 confirmed cases have been identified in South Africa, Hong Kong and Botswana.

The variant has over 30 mutations – around twice as many as the Delta variant – which could potentially make it more transmissible and evade the protection given by prior infection or vaccination.

Experts from the UKHSA have been advising ministers on the issue.

A number of scientists have expressed serious concern over the variant due to the significant number of mutations in the spike protein.

One senior scientist said: “One of our major worries is this virus spike protein is so dramatically different to the virus spike that was in the original Wuhan strain, and therefore in our vaccines, that it has a great cause of concern.”

Experts from the World Health Organisation (WHO) are meeting with South African officials on Friday to assess the evolving situation in the country.

The variant could eventually be given the moniker “Nu” – with the most concerning variants given named after the Greek alphabet.

Of the 59 lab confirmed cases of the new variant, three were in Botswana, two were in Hong Kong among people who had travelled from South Africa, and the remaining were confirmed in South Africa.

UK officials were said to be “very worried” after they examined details on the variant on the international database – and have taken significant steps just three days after the details were uploaded.

The variant is a “dramatic change” from anything seen previously by UK scientists.

It has mutations which have been observed in other variants, but also ones that scientists have not yet seen.

As such, they think that if a new vaccine were needed to combat the variant, it could take some time.

But officials do not yet have enough evidence to call it a “variant of concern”.

As of yet there is not good evidence on transmissibility or the impact on vaccine effectiveness, and there is also no evidence on whether or not it causes more severe disease.

The risk of reinfection is not known, but it is expected a picture on this will develop quickly – this would be the first signal the variant could evade the body’s defences.

Experts have predicted “some reduced vaccine effect” but are not able to judge how bad it could be.

Some compared it to the Beta variant – which saw vaccine efficacy reduced by 30%-40%.

While there have been no cases seen in the UK yet, it is always possible that a case could have slipped in – but officials think that the likelihood of cases remains “low”.

Health officials said that Covid-19 booster jabs have become “particularly critical” given the development.