Omicron coronavirus variant

How will the Omicron coronavirus variant affect Europe this winter?

Scientists are concerned that the B.1.1.529 mutation could bypass immunization from both vaccination or prior infection.

BY HELEN COLLIS

A new variant of coronavirus has sparked a frenzy of investigations and travel interventions as experts seek to get ahead in understanding just how serious this mutation really is.

The variant, named by the World Health Organization as Omicron, was first detected by genomic sequencing in South Africa and shared with an international database on November 22.

“This variant has a large number of mutations, some of which are concerning,” the WHO said in a statement on Friday. “Preliminary evidence suggests an increased risk of reinfection with this variant, as compared to other [variants of concerns]."

Jenny Harries, head of the U.K.’s Health Security Agency said earlier this was the “most significant variant we have encountered to date” and said “urgent research” was underway to understand more.

In response to concerns raised by scientists, the U.K. government, followed by others in Europe, announced significant restrictions to travel from South Africa, Botswana, Lesotho, Eswatini, Zimbabwe and Namibia. But the variant has already spread to Europe, with one case detected in Belgium.

Here’s what we know so far about the variant — and what we don’t know.

Why have scientists raised concerns about this variant?

The Omicron variant, also known as B.1.1.529, contains around 50 mutations, an unusually large number. More than 30 of these are in the spike protein, the part of the SARS-CoV-2 virus that interacts with human cells prior to cell entry — and the part most vaccines target.

While several of those mutations have been observed in earlier variants of concern, “some of those mutations have rarely been observed together in the same strain before,” said Francois Balloux, director of University College London’s Genetics Institute.

Genomic sequencing in South Africa has so far identified 100 Omicron cases from the region that includes the cities of Johannesburg and Pretoria. Previously low overall daily COVID-19 case rates in that part of the country have spiked over the past seven days from 273 to more than 1,200.

Will my vaccine still protect me?

Based on the number and types of mutations seen in the Omicron variant, scientists suggest that immunity through vaccination and/or prior infection may not protect against re-infection by Omicron so effectively.

“Based on its genetic makeup, we can confidently predict B.1.1.529 may partly bypass immunization provided by vaccination and prior infection,” said Balloux.

That’s because mutations in Omicron “have been associated in other variants with immune evasion,” pointed out Sharon Peacock, director of COG-UK Genomics U.K. Consortium.

But it will be a few weeks before we know for sure.

Lab studies are being conducted rapidly in South Africa to understand the impact on immunity. Scientists are looking at antibody neutralization of this variant as well as interactions with T cells, to “confirm whether there is reduced immunity in standard lab assays, but these will take several weeks to complete,” said Peacock, who is also professor of public health and microbiology at the University of Cambridge.

Meanwhile, there is currently no real-world evidence that immunity to vaccines and past infection is reduced, she said, and these studies are needed.

Is this variant likely to become dominant in Europe?

This is unknown at this stage. Current data shows a spike in cases particularly in the Gauteng province of South Africa.

“The epidemiological picture suggests that this variant may be more transmissible, and several (of the Omicron) mutations are consistent with enhanced transmissibility,” said Peacock. But it was not yet clear whether this was due to super-spreading events or whether the Omicron variant can in fact outcompete the now-dominant Delta strain. "Further studies are required to confirm this,” Peacock said.

“Any prediction about its transmissibility and virulence feels premature,” added Balloux. “While we can work out the contribution to transmissibility and virulence of mutations in isolation, we still struggle to accurately predict their effect when found in combination.”

Is this variant more deadly?

Once again, data on this is still pending, and will most likely come from ongoing surveillance in South Africa.

One school of thought suggests that if Omicron is more transmissible, it may be less dangerous — from the evolutionary point of view a virus risks extinction if it is too effective at killing its host. This could also be the case with the Delta sub-lineage AY.4.2 which is gaining pace in the U.K.

Meanwhile, some suggest that the cellular immune response induced by vaccines may be sufficient to fight off the virus even with multiple mutations.

Monica Gandhi, an infectious diseases/HIV doctor at University of California, San Francisco, tweeted that, since the cellular immune response is very complex — generating new types of antibodies even against new variants — there is a chance vaccines will remain protective.

How can we protect ourselves?

It’s still not known to what extent the Omicron variant may escape vaccine immunity. Experts urge people to get their full course of vaccination, including boosters if eligible.

The U.K. and Europe have taken quick action to try to stem the flow of the Omicron variant into the region, through temporarily stopping flights and introducing new quarantine measures.

“Early action is far better than late action,” said Ewan Birney, deputy director general of European Molecular Biology Laboratory and director of EMBL’s European Bioinformatics Institute. “It may turn out that this variant is not as large a threat as Alpha and Delta, but the potential consequences of not acting on the possibility it could be are serious,” he added.

Meanwhile, the international community “should get drugs and vaccines to South Africa as soon as possible,” he added.

If we need new vaccines, how long would it take to make them?

The most widely used vaccine in Europe has been the mRNA COVID-19 shot from BioNTech/Pfizer. These companies are looking out for vaccine escape variants, including Omicron.

“We expect data from the laboratory tests in two weeks at the latest,” a spokesperson for BioNTech said. “These data will provide more information about whether B.1.1.529 could be an escape variant that may require an adjustment of our vaccine if the variant spreads globally."

Pfizer Chief Executive Albert Bourla said in September that the two companies could develop a new version of the vaccine that is tailor-made made to a new variant in “less than 100 days.”

The companies have already done this for the Beta variant, also first identified in South Africa, and Delta. But since the current vaccine has remained effective against these variants, there has not yet been any need to bring a modified version to market.

Earlier this month, BioNTech announced it was developing a prototype approach to evaluate the development, manufacturing and regulatory processes for variant specific vaccines, so they could arrive much quicker.

“The idea is that we're staying ahead of the virus,” Bourla said in September.