What do we know about the Omicron COVID-19 variant so far?

The Omicron variant is the latest strain of the coronavirus to be detected and has been designated as a ‘variant of concern’ by the World Health Organisation (WHO).

While countries worldwide continue to report cases, scientists are still trying to determine whether the current vaccines are effective against it. This is a guide on what we know so far about this heavily-mutated virus.

Where did Omicron originate from?

The South African authorities first reported the Omicron variant to the WHO on 24 November following an increase in cases in the Gauteng province.

The first known and confirmed infection with Omicron was from a sample taken on 9 November, and since then, the number of Omicron cases has continued to rise. However, although the variant was found in South Africa, it is unclear what country it emerged from.

Many countries, including Malta, have put travel bans South Africa and its neighbouring countries as a result.

Where has Omicron been detected so far?

As of last week, there have been at least 22 confirmed positive cases in South Africa. On Sunday, the Dutch authorities confirmed that at least 13 people who arrived on flights from South Africa had tested positive for the Omicron variant.

In Portugal, 13 members of a football team tested positive for the variant on Monday. There have also been six cases in Scotland and three cases across the rest of the UK.

The Omicron variant has also been detected in travellers returning from African countries to Hong Kong, Belgium and Israel, and in European countries including Italy, Germany and the Czech Republic.

What makes Omicron of concern?

It is the number of mutations the virus has that makes it a matter of concern.The Omicron variant has more than 30 mutations in the genes that code for the spike protein. According to The Guardian, of these mutations, 10 are in the "receptor binding domain," or the part of the spike protein that latches onto human cells.

"The likelihood of potential further spread of Omicron at the global level is high," the WHO said.

What is the severity of the Omicron variant?

Early evidence suggests hospitalisation rates are increasing in South Africa. However, the WHO said this might be due to rising numbers overall rather than the Omicron variant.  

Only about 24% of South Africa's population is fully vaccinated against COVID-19.

However, only about 6% of the population of South Africa is older than the age 65. So it's unclear whether the variant will cause more severe disease in those who are at increased risk, such as older people.

What are the symptoms?

A BBC interview with Dr Angelique Coetzee, a private practitioner and chair of the South African Medical Association, said that the patients she's seen so far with the new variant have had "extremely mild" symptoms.  

It is also not clear if the Omicron spreads more easily from person to person. However, the number of people in South Africa who have been testing positive for COVID-19 has increased in areas battling Omicron.

How effective are current COVID vaccines?

Experts say that while vaccines may be less effective against Omicron than previous variants, they will probably still confer some protection.

Most COVID-19 vaccines prime the immune system specifically against the spike protein. Because Omicron has many mutations in the spike protein, experts are worried that current vaccines may be less effective at training the immune system to recognise it.

Vaccine manufacturers Pfizer-BioNtech and Moderna have said they require more information to determine the effectiveness of their vaccines against Omicron. It would take less than 100 days for these manufacturers to alter their vaccines to be able to counter any new variant.