The World Health Organization warned that the new coronavirus variant could fuel surges with “severe consequences” amid signs that it makes Covid-19 more transmissible.
South African scientists, who first discovered omicron, stated that it spreads more quickly, but the existing vaccines can still protect against serious illness. The Geneva-based WHO assessed the variant’s risk as “extremely high” and called on member states to test widely. According to the agency, it could take several days and even weeks for the public to fully understand this new strain.
“We don’t have enough data to determine vaccine effectiveness against omicron or disease severity, so any claims about either at this stage are not evidence-based,” said Raina MacIntyre, professor of global biosecurity at the University of New South Wales in Sydney. “So far, the virus has not mutated to become less severe — in fact the opposite.”
Travel bans are being implemented by governments around the globe for South African and other nearby countries. This is in response to concerns that omicron might evade vaccinations, worsen Covid surges, and impede efforts to open up economies. Although the announcement of the new variant caused havoc on global financial markets Friday, Asian trading Monday showed that investors were still waiting to see more details as scientists try to understand it better.
Omicron’s mutations may make it easier for the virus to evade existing immunity, the WHO said in a technical briefing document for its members. It warned of “future surges of Covid-19, which could have severe consequences.”
It was detected for the first times earlier this month. It’s characterized by some 30 or more genetic changes, half of which are in the part of the spike protein used to bind to human ACE-2, which is the enzyme the coronavirus targets to enter cells and cause an infection. These mutations can cause spike proteins to be less readily recognized by the natural or vaccine-induced antibodies.
The U.K. government will convene an urgent meeting of Group of Seven health ministers Monday to discuss the latest developments, according to the country’s Department of Health. According to the White House, Monday will see President Joe Biden give an update in the U.S.
Angelique Coetzee, chair of the South African Medical Association, called symptoms associated with the variant at this point “different and so mild” compared with others she’s treated in recent months.
Coetzee, who first spotted what turned out to be the new variant, told the U.K.’s Telegraph newspaper that a number of healthy young men turned up at her clinic “feeling so tired.” About half were unvaccinated.
“What we are seeing clinically in South Africa and remember, I’m at the epicenter, that’s where I’m practicing, is extremely mild,” she said Sunday on the BBC’s “Andrew Marr Show.”
Asked if authorities around the world were panicking unnecessarily, Coetzee said, “Yes, at this stage I would say definitely. Two weeks from now on maybe we will say something different.”
However, experts elsewhere urged caution.
Richard Lessells, an infectious-diseases physician at the University of KwaZulu-Natal in Durban, said a rapid understanding of disease severity caused by omicron is critical, but it’s too early for reliable data. The time it takes for infections to progress to severe disease or hospitalization means omicron’s impact may not be apparent for a few more weeks.
“Observations from clinicians on the ground are always important, and we lean heavily on them, but we need to be cautious about jumping on early reports that all cases with this variant are mild,” Lessells said in a Twitter post Sunday.
The variant’s genome contains “some concerning elements,” said Stephen Goldstein, an evolutionary virologist at the University of Utah in Salt Lake City. He said that their effect on vaccine efficacy should be known within the next few weeks. Omicron has also some mutations close to the furin cleavage sites of spike proteins that can increase transmissibility for both alpha and beta variants.
“We’re starting to see cases pop up in other parts of the world, so it appears to be spreading quite quickly, which leads to concerns that it may be even more transmissible than delta, but it really is too soon to say,” Goldstein said in a Zoom interview. He said that any advantage Omicron may have will be more apparent if the virus spreads to parts of Europe and the U.S., which are already fighting delta-fueled diseases.
South Africa’s average daily case count increased to 1,600 from just 500 cases the previous week, and there were 275 new infections during the preceding week, President Cyril Ramaphosa stated Sunday. In less than one week, the proportion of positive Covid test results jumped from 2% to 9%.
No unusual symptoms have been reported following infection with omicron and, as with other variants, some individuals are asymptomatic, South Africa’s National Institute for Communicable Diseases said Friday. South Africa has only 36% complete vaccination.
The two cases of omicron in Australia were detected after vaccinated individuals did not show any symptoms. One man aged 62 who contracted the disease in Hong Kong’s quarantine facility did experience symptoms. These infections can be detected in both places by negative Covid tests.
The WHO said there was preliminary data showing a higher number of hospitalizations, “but this may be due to increasing overall numbers of people becoming infected, rather than a result of specific infection with omicron.”
—With assistance from Stuart Biggs, Ainslie Chandler, Jinshan Hong and S’thembile Cele.