The mysteries of Omicron may take weeks to unravel
A pandemic-weary world faces weeks of confusing uncertainty as countries restrict travel and take other steps to halt the newest potentially risky coronavirus mutant before anyone knows just how dangerous omicron really is.
Will it spread even faster than the already extra-contagious Delta variant? Does it make people sicker? Does it evade vaccines’ protection or reinfect survivors? There are lots of guesses but little hard evidence as scientists race to find answers amid scrutiny from an anxious public.
“Pretty much the right level of freaking out,” is how Trevor Bedford, who studies evolution of the coronavirus at the Fred Hutchinson Cancer Research Center in Seattle, Wash., characterized health experts’ reactions.
Omicron might not turn out “as bad as we’re perhaps imagining it could be but treating it as such at the moment I think is entirely appropriate,” he said.
Up to now, the world has been slow to react to each coronavirus curveball. This time an early warning from South Africa and Botswana might have offered important head start.
“It’s hard to know: Have we just simply caught up to the reality and now the world is reacting with the appropriate speed as variants emerge?” asked Dr. Jacob Lemieux, who monitors variants for a research collaboration led by Harvard Medical School.
Why the worry?
Omicron raised alarm because of its sheer number of mutations, more than prior variants had. Possibly 30 are in a key place, the spike protein that lets the virus attach to human cells. Scientists recognize a few mutations from earlier variants that were more contagious or a bit resistant to vaccination. But they’ve never seen this particular constellation of changes.
Scrambling for answers
Scientists have little data yet on whether Omicron causes more severe disease than other variants. And while it already has been diagnosed in numerous countries just days after its discovery was announced, it’s also too soon to know how contagious it is.
The Alpha variant that emerged about a year ago was more transmissible than the virus that started the pandemic. Then Delta hit, far more contagious than Alpha.
It’s unclear how Omicron would compete in a place like the U.S. where that strong Delta variant is causing more than 99% of current COVID-19 cases, said Louis Mansky, director of the Institute for Molecular Virology at the University of Minnesota.
Even in certain parts of South Africa, a reported jump in Omicron caused cases may not indicate the mutant is more contagious than Delta, Lemieux said.
“We really don’t know if Omicron is out-competing Delta at all or whether it’s become the dominant strain in a few places just due to chance,” he said.
To understand Omicron better, scientists are trying to figure out how it emerged. It’s not a descendent of Delta. One popular theory is that someone with a severely weakened immune system had a coronavirus infection they couldn’t shake for so long that mutations stacked up.
“This is completely bizarre,” said Bedford, whose says variants that were circulating in summer of 2020 appear to be Omicron’s closest relatives.
What to do now?
Scientists urge people to take simple precautions as they wait for answers — mask indoors, avoid crowds, get the shots if you are among those who still haven’t been vaccinated — regardless of what variant’s circulating.
“People who are on the fence about whether to get vaccinated should see a great reason to get vaccinated. People who haven’t yet gotten their boosters and are eligible should get their boosters. And then I think we need to let the scientists and the public health practitioners do their work,” Lemieux said.
Scientists say it may take two to four weeks to get some important answers.
Among the biggest concerns is how much Omicron might evade immunity. So far the Beta variant has been the biggest challenge to vaccine protection but that mutant fortunately didn’t spread widely.
“It is highly unlikely that this new variant has escaped all antibodies generated following vaccination,” said immunologist E. John Wherry of the University of Pennsylvania.
Vaccine makers and other scientists are setting up lab tests to tell how well antibodies generated by vaccines or prior infection can fight Omicron compared to earlier variants.
It takes time because first, they must grow samples of so-called “pseudoviruses” that hold the worrisome new mutations.