Omicron Variant Could Displace Delta: Top WHO Scientist

Travelers receive COVID-19 tests at a pre-departure testing facility, as countries react to the new Omicron variant, outside the international terminal at Sydney Airport in Australia on Nov. 29, 2021. Loren Elliott/Reuters

The World Health Organization’s (WHO) chief scientist says the new Omicron COVID-19 variant could displace the Delta variant, which emerged earlier this year as the dominant strain, while researchers recently announced that Omicron may have picked up genetic material from the common cold.

Soumya Swaminathan said it’s not yet clear whether Omicron is milder than other CCP (Chinese Communist Party) virus variants, while casting doubt on whether it emerged in southern Africa.

“It is possible that it could become [the] dominant variant,” Swaminathan said during a Reuters event on Dec. 3, adding that it’s impossible for scientists to make that prediction. The Delta variant, she said, accounts for 99 percent of COVID-19 cases around the world.

Despite that, Swaminathan said Omicron—named as such by the WHO more than a week ago—is “highly transmissible,” based on preliminary data from southern Africa. The WHO courted controversy for naming the variant Omicron, skipping over naming it “Xi,” a letter in the Greek alphabet.

“How worried should we be? We need to be prepared and cautious, not panic, because we’re in a different situation to a year ago,” Swaminathan said, according to Reuters. Also unclear is Omicron’s effect on vaccinated people or individuals who have gained natural immunity from a prior COVID-19 infection, she said.

In a preliminary study, researchers wrote on Dec. 3 that Omicron is the only CCP virus variant to contain an “insertion mutation,” dubbed ins214EPE, which the researchers said is likely of human genomic or viral origin.

The researchers then theorized in a pre-print study that the insertion mutation may have developed in a person simultaneously infected with SARS-CoV-2, also known as the CCP virus, and the HCoV-229E coronavirus, which can cause the common cold.

“It is plausible that the Omicron insertion could have evolved in a co-infected individual,” the researcher team, led by Venky Soundararajan of nference, a Cambridge, Massachusetts-based firm that analyzes biomedical information, wrote in the study.

To date, more than 20 cases of Omicron have been reported in the United States, while worldwide, no deaths have been reported to be associated with the new variant. A top doctor in South Africa last week, in a media blitz, revealed that Omicron patients generally have shown “extremely mild” symptoms so far.

But Swaminathan told Reuters that there’s no conclusive evidence showing Omicron is a milder variant than the Delta or Alpha strains.

“It does seem to be able to overcome some of the natural immunity from previous infection,” the U.N. health agency official said. “The fact that they’re not getting sick ... that means the vaccines are still providing protection, and we would hope that they would continue to provide protection,” Swaminathan said.

The United States, the European Union, and various countries have since imposed travel restrictions on several southern African countries, while Japan and Israel have barred all foreign travel over the emergence of the variant.

Tom Ozimek contributed to this report.