Global concern about the coronavirus pandemic is growing, with a number of countries detecting confirmed cases of the Omicron variant for the first time.
Travel restrictions are also being imposed once again as governments suspend flights from southern Africa, the region where this strain was first detected.
Here is a look at the latest COVID-19 developments around the world.
On Saturday, Israel unveiled plans to ban all foreigners from entering the country.
If the proposals are approved, it will become the first nation to completely shut its borders in response to the Omicron variant.
There are fears that B.1.1.529 could be more contagious than other variants – and more resistant to vaccines.
Prime Minister Naftali Bennett said the ban would last for 14 days.
So far, Israel has one confirmed case of the Omicron variant, and seven suspected cases.
Phone-tracking technology is going to be used to locate carriers of the new variant, in an attempt to stop it being transmitted to others.
From Monday, the US is going to restrict travel from South Africa and seven other countries in the region.
American citizens and permanent US residents – along with spouses and close friends – will be exempt.
No cases linked to Omicron have been detected in the country so far.
But Dr Anthony Fauci, America’s top infectious disease specialist, told NBC that he wouldn’t be surprised if the variant is already in the States, adding: “When you have a virus that is showing this degree of transmissibility … it almost invariably is ultimately going to go essentially all over.”
In separate developments, New York Governor Kathy Hochul issued a COVID-19 “disaster emergency” declaration on Friday, with infections and hospitalisations increasing in the state.
On Saturday, health officials confirmed that a case of the Omicron variant had been detected in Italy.
The business traveller had flown from Mozambique, landing in Rome on 11 November and returning to his home in Naples.
Five of his family members, including two children, have also tested positive. All are now isolating and have light symptoms.
The Omicron variant has also been detected in two travellers who arrived on a flight from South Africa on 24 November.
Although genome sequencing is yet to be completed, it is “proven without doubt that this is the variant”.
Both cases were detected in the southern state of Bavaria, and another suspected case has been found in the west of the country.
Dutch health officials have detected 61 COVID-19 cases among people who flew from South Africa on Friday.
Although the Netherlands Institute for Health is “almost certain” some of these patients have the Omicron variant, further testing is required to be absolutely sure.
The KLM airline expressed surprise at the high number of cases because all passengers had either tested negative or shown proof of vaccination before boarding flights from Cape Town and Johannesburg.
Authorities in the country are now attempting to contact 5,000 passengers who have travelled from South Africa, Botswana, Eswatini, Lesotho, Mozambique, Namibia or Zimbabwe since Monday.
Quarantine requirements have been widened to a greater number of travellers in an attempt to stem the spread of the Omicron variant.
Those arriving from the UK, the Czech Republic, the Netherlands, Egypt and Malawi will now be subject to tighter restrictions.
The Federal Office of Public Health said passengers from these countries will need to present a negative COVID-19 test and quarantine for 10 days too.
Direct flights have already been banned from South Africa and the surrounding region.
Despite cases being detected in Italy and Germany, both neighbours of Switzerland, travel restrictions have not been imposed on any countries it shares borders with.
From next month, British tourists will only be able to enter Spain if they can show proof of a COVID-19 vaccination.
Until now, unvaccinated travellers were allowed into the country if they could present a negative PCR test that was take 72 hours before their arrival.
“The appearance of new variants causing (coronavirus) obliges an increase in restrictions,” the government said.
Spain’s Industry, Trade and Tourism department said approximately 300,000 British people who are resident in Spain will not be affected by the new measures.