The B.1.1.529 variant exhibits an “extremely high number” of mutations, which raises concerns for the efficacy of existing vaccines.
Scientists have detected a new variant of Covid-19 in South Africa, carrying an “extremely high number” of mutations. This feature raises concerns about the efficacy of existing vaccines. So far, only ten cases in three countries have been confirmed using genomic sequencing.
This variant, called B.1.1.529, was first spotted in Botswana on November 11, where three cases have now been sequenced. Six more cases have been confirmed in South Africa, and one in Hong Kong in a traveler returning from South Africa.
“As it is in the nature of viruses to mutate frequently and randomly, it is not unusual for small numbers of cases to appear with new sets of mutations. Any variants showing signs of spreading are quickly evaluated,” explains Meera Chand, research director at the British Health Safety Agency in the Guardian.
A large number of mutations
According to the researchers, the variant has 32 mutations in the spike protein, the part of the virus that most vaccines use to trigger the immune system against Covid. Mutations in the spike protein can therefore affect the ability of the virus to infect cells and spread, but also make it more difficult for the pathogen to be attacked by immune cells from the vaccine.
According to Ravi Gupta, professor of clinical microbiology at the University of Cambridge, two of the mutations in B.1.1.529 increase infectivity and reduce antibody recognition. “Certainly this appears to be a significant concern. However, a key property of the virus that is not known is its infectivity, as this is what appears to have primarily motivated the Delta variant,” he explains in The Guardian.
Professor François Balloux, director of the Institute of Genetics at UCL, said the large number of mutations in this variant accumulated at one time, suggesting that it may have evolved over the course of a chronic infection in a person with a weakened immune system, possibly an untreated patient with HIV.
Worrying situation in South Africa
Scientists will monitor the new variant for any signs that it is gaining momentum and spreading more widely. Some South African virologists are already worried, especially given the recent increase in cases in the Gauteng, an urban area comprising Pretoria and Johannesburg, where B.1.1.529 has been detected.
The appearance of this variant is undoubtedly at the origin of the “exponential” increase in contamination in recent weeks, said South African Minister of Health, Joe Phaahla, at a press conference on Thursday. South Africa, which fears a new wave of the pandemic by the end of the year, is officially the most affected by the pandemic on the continent. It has more than 2.9 million cases and more than 89,600 deaths.