Prominent South African scientists have raised a new omicron caution, saying that it is too soon to say whether the omicron form will only cause moderate disease. In comparison to western countries, South Africa has a low immunisation rate.
The true impact of the coronavirus strain is currently difficult to determine because it has mostly affected young people, who are better able to fight off the pathogen, and people tend to get sicker after carrying the virus for a long time, according to the scientists, who presented their findings to lawmakers on Wednesday.
On 26 November 2021, WHO designated the variant B.1.1.529 a variant of concern, named Omicron, on the advice of WHO’s Technical Advisory Group on Virus Evolution (TAG-VE). This decision was based on the evidence presented to the TAG-VE that Omicron has several mutations that may have an impact on how it behaves, for example, on how easily it spreads or the severity of illness it causes. Here is a summary of what is currently known.
On Nov. 25, the South African government and scientists announced that a new variant, later christened omicron by the World Health Organization, had been found in the country. That triggered an equity market sell-off and led to the imposition of travel bans on several southern African nations.
Richard Lessells, an infectious disease specialist at the KRISP genomics institute, said the severity of disease caused by the new strain may also be masked by the fact that many people have already contracted other variants or have been inoculated, giving them some immunity.
New Omicron Caution: The dominant strain in Africa
Earlier the National Institute for Communicable Diseases said the daily number of new confirmed cases in South Africa almost doubled to 8,561 infections in the last 24 hours. Omicron is now by far the dominant strain in the country.
The latest infections have occurred “mostly in the younger age groups but we are starting to see this move into the older age groups,” Michelle Groome, head of public health surveillance and response at the NICD, told the lawmakers. “We are also expecting that the more severe complications may not present themselves for a few weeks.”
“If this virus and this variant spreads very efficiently through the population, then it will still be able to find those people in the population who are unvaccinated and may be unprotected against severe disease,” he said. “That’s what also concerns us when we think about the continent more generally.”
South Africa’s vaccination rate is low compared with western nations and China but is well above most African nations, with about a quarter of the population fully inoculated. Across the continent of 1.3 billion people, only 6.7% are fully vaccinated, with only 0.1% of the 100 million people in the Democratic Republic of Congo having received their shots.
Even so, Lessells expects that while the variant may evade antibodies the body’s other defenses, such as T-cells, may still be effective. T-cells kill infected cells.
“We expect that the protection you have against severe disease is much more difficult for this variant to get around,” he told the lawmakers. “We don’t expect this will have any effect on the therapeutics we use.”
What we know of Omicron till now
Researchers in South Africa and around the world are conducting studies to better understand many aspects of Omicron and will continue to share the findings of these studies as they become available.
Transmissibility: It is not yet clear whether Omicron is more transmissible (e.g., more easily spread from person to person) compared to other variants, including Delta. The number of people testing positive has risen in areas of South Africa affected by this variant, but epidemiologic studies are underway to understand if it is because of Omicron or other factors.
Severity of disease: It is not yet clear whether infection with Omicron causes more severe disease compared to infections with other variants, including Delta. Preliminary data suggests that there are increasing rates of hospitalization in South Africa, but this may be due to increasing overall numbers of people becoming infected, rather than a result of specific infection with Omicron.
