In the rush to understand the threat posed by the omicron variant, the worrisome new version of the coronavirus, some experts are pointing hopefully to early signs that it may cause only mild illness, without some of the trademark symptoms of covid.
[Video not showing up above? Click here to watch » arkansasonline.com/1129coetzee/]
But it is far too early to assume that the variant will not cause severe illness, too, warned Dr. Richard Lessells, who coordinates clinical and epidemiological data for the South African covid Variant Research Consortium.
Many of the early infections in South Africa were spotted among younger people more likely to experience mild illness, he said. The picture may change as the virus spreads through the larger population.
At the moment, the variant has been spotted in at least a dozen countries, including Britain and the Netherlands. Many others are closely monitoring cases. Omicron has not yet surfaced in the United States, according to the Centers for Disease Control and Prevention.
[Video not showing up above? Click here to watch » arkansasonline.com/1129collins/]
Omicron has dozens of new mutations, including many that may enable the virus to be more contagious and to sidestep immune defenses. But Dr. Angelique Coetzee, who chairs the South African Medical Association, noted Saturday that the nation's hospitals were not overrun by patients infected with the new variant and that most were not fully immunized.
Moreover, most patients she had seen did not lose their sense of taste and smell, and had only a slight cough, she told reporters.
But that may not be as reassuring as it sounds. Most of South Africa's cases were initially found in the Gauteng province, mostly among younger people at universities and higher education institutions, said Lessells, who is also an infectious-disease physician at the University of KwaZulu-Natal.
"We would, of course, expect the vast majority of those to be mild cases anyway, regardless of vaccination status," he said.
In addition, cases overall have also been rising only in the past two weeks, Lessells noted: "There's even barely enough time for infections to have had time to progress to severe disease and hospitalization."
Should omicron cause severe illness, that will become apparent if there is a significant rise in hospitalizations over the next week or two, he added.
Scientists have not yet analyzed infections in fully immunized people, but they are already seeing some cases of reinfection that suggest the variant can overcome natural immunity, Lessells said.
He and his colleagues plan to review the latest data today to spot trends and to plan for omicron's spread.
After convening a group of experts to assess the data, the World Health Organization said that "preliminary evidence suggests an increased risk of reinfection with this variant" compared with other variants.
That means people who contracted covid-19 and recovered could be subject to catching it again.
The variant appears to have a high number of mutations -- about 30 -- in the coronavirus' spike protein, which could affect how easily it spreads to people.
Sharon Peacock, who has led genetic sequencing of covid-19 in Britain at the University of Cambridge, said the data so far suggests the new variant has mutations "consistent with enhanced transmissibility," but said that "the significance of many of the mutations is still not known."
Lawrence Young, a virologist at the University of Warwick, described omicron as "the most heavily mutated version of the virus we have seen," including potentially worrying changes never before seen all in the same virus.
Scientists know that omicron is genetically distinct from previous variants including the beta and delta variants, but do not know if these genetic changes make it any more transmissible or dangerous. So far, there is no indication the variant causes more severe disease.
It will likely take weeks to sort out if omicron is more infectious and if vaccines are still effective against it.
Peter Openshaw, a professor of experimental medicine at Imperial College London, said it was "extremely unlikely" that current vaccines wouldn't work, noting they are effective against numerous other variants.
Even though some of the genetic changes in omicron appear worrying, it's still unclear if they will pose a public health threat. Some previous variants, such as the beta variant, initially alarmed scientists but didn't end up spreading very far.
"We don't know if this new variant could get a toehold in regions where delta is," Peacock said. "The jury is out on how well this variant will do where there are other variants circulating."
To date, delta is by far the most predominant form of covid-19, accounting for more than 99% of sequences submitted to the world's biggest public database.
The coronavirus mutates as it spreads and many new variants, including those with worrying genetic changes, often just die out. Scientists monitor covid-19 sequences for mutations that could make the disease more transmissible or deadly, but they cannot determine that simply by looking at the virus.
Peacock said the variant "may have evolved in someone who was infected but could then not clear the virus, giving the virus the chance to genetically evolve," in a scenario similar to how experts think the alpha variant -- which was first identified in England -- also emerged, by mutating in an immune-compromised person.
Information for this article was contributed by Apoorva Mandavilli of The New York Times and by Maria Cheng of The Associated Press.