Questions abound on the potential threat to public health from the Omicron coronavirus variant, which was identified last month by health officials in South Africa.

The new strain was isolated in the port of Durban, the country’s third-largest city.

The BBC reported over the weekend that scientists in South Africa believed Omicron was more capable of infecting people who had earlier recovered from Covid-19.

The variant has significantly higher mutations than those seen in previous coronavirus mutations such as Delta – the strain found in 100 per cent of Bermudian cases where virus typing was available.

· Where is it?

After spreading in Africa, Omicron began appearing in Europe, with cases surging over the weekend in the UK and Denmark.

The UK health security agency reported on Twitter last Sunday that known cases had climbed to 246.

News agency Reuters reported Omicron had appeared in one third of US states on the same day.

· Is it considered more serious than previous variants?

The BBC quoted a South African vaccine researcher’s claim that early evidence showed Omicron "may be more transmissible than even Delta, Alpha or Beta" – all of which have featured in Bermuda’s outbreaks.

· When did it appear?

The new strain, B. 1.1.529, became “a variant of concern” to the World Health Organisation (WHO) on November 26

The WHO named it Omicron, in line with the convention of using letters of the Greek alphabet.

· How much faster can it spread?

The New York Timesreported last Friday that epidemiology figures from South Africa suggested the strain could be transmitted up to twice as fast as the Delta variant – which had been thought to be the most contagious variety.

Tom Wenseleers, an evolutionary biologist at the Catholic University of Leuven in Belgium, said in The Guardian hebelieved Omicron could “infect three to six times as many people as Delta, over the same time period”.

He told the journal Nature: “That’s a huge advantage for the virus – but not for us.”

When the Delta variant began its rapid spread in the UK, case numbers about doubled every five days. Scientists are now monitoring Omicron cases to determine how fast the variant has affected the population of Britain.

· Can it evade the vaccines against Covid-19?

Reuters reported last week that manufacturers of the vaccine had said it could take “take two to three weeks” to determine the jab’s efficiency against Omicron.

Optimistic news was reported in the The Observer last Sunday that the new strain would be “extremely unlikely” to be unaffected by vaccination.

But it was warned more information was needed to determine how useful existing vaccines were against Omicron.

Francois Balloux, the director of the Genetics Institute at University College London, said in The Guardian: “From what we have learned so far, we can be fairly confident that – compared with other variants – Omicron tends to be better able to reinfect people who have been previously infected and received some protection against Covid-19.

“That is pretty clear and was anticipated from the mutational changes we have pinpointed in its protein structure. These make it more difficult for antibodies to neutralise the virus.”

· Where has travel been restricted?

The announcement from South Africa caused the US and UK to ban travel from a string of countries across southern Africa.

New requirements came into effect in the US for international air travellers on Monday. The US now requires a clear Covid-19 test from the day before travel instead of within 72 hours of travel – although faster antigen tests are acceptable as well as PCR tests.

The US Centres for Disease Control yesterday advised US citizens to avoid France, Jordan, Portugal and Tanzania as more than 80 destinations were added to its “Level 4 – Very High” risk classification.

· How are people in higher risk groups affected?

The World Health Organisation said last Friday it had yet to see any reports of deaths related to Omicron.

But Rowland Kao of Edinburgh University told The Guardian: “The big issue is the elderly population.”