Q&A on the Omicron Variant
On Nov. 24, South Africa told the World Health Organization that amid a recent increase in COVID-19 cases, it had identified a new variant — later named omicron — with a high number of mutations, raising concerns that it could spread more easily than other variants of the coronavirus.
The next day, South Africa’s health minister, Joe Phaahla, said the variant, also called B.1.1.529, had been identified in South Africa, Botswana and a person who had traveled from South Africa to Hong Kong. The WHO gave the variant its Greek alphabet name on Nov. 26 and labeled it a “variant of concern,” meaning it could be associated with an increase in transmissibility or virulence, or a decrease in effectiveness of vaccines.
Other countries quickly announced travel restrictions on visitors from South Africa and nearby African countries, but just as quickly, confirmed cases due to omicron cropped up in Europe, Israel, Australia and Canada. The specimen for the first confirmed case in South Africa had been collected on Nov. 9. Not quite a month later, on Dec. 1, the U.S. had its first confirmed case — in California, in a person who had returned from South Africa on Nov. 22, and several more cases followed.
Scientists have cautioned that while there are reasons to be concerned about omicron, it’s not yet known whether the variant is more likely than others to spread easily or cause severe disease. Preliminary evidence suggests those who previously had COVID-19 could more easily be reinfected with this variant, as opposed to others. But the WHO said studies are underway to assess all of this, as well as the effectiveness of the available vaccines and treatments against omicron.
We’ll go through what we know so far about omicron.
Why are experts concerned about the omicron variant?
Much of the concern is related to the mutations present in the virus. As soon as sequencing efforts in Africa identified several instances of a new version of the coronavirus on Nov. 23, scientists noticed that the virus has an unprecedented number of mutations — 50 or more — across its genome.
Worryingly, many of the mutations occur in the gene that makes the spike protein, or the outside part of the virus that SARS-CoV-2 uses to enter cells, raising the possibility that those modifications could affect viral transmission or the immune response.
Many of the mutations have also appeared before in other variants of concern — including those associated with increased transmissibility and immune evasion — although some are new.
It’s hard to predict from a sequence how all of the mutations will work together, though, so it’s too early to know what this all means and how omicron will behave. But many experts are on alert.
“Omicron is concerning and we should be paying attention,” E. John Wherry, an immunologist at the University of Pennsylvania, told us, although he added that it was “not a cause for panic.” Even if there is some reduction in the effectiveness of vaccines, he said, it’s likely the shots would still retain some ability to protect against severe disease, hospitalization and death.
This preliminary epidemiological evidence also suggests the variant might
