What is the South African Covid variant and why is it more worrying?
Ever since scientists started tracking the SARS-CoV-2 virus that causes COVID-19, it has become a cause for concern that the virus has developed multiple variants that began emerging in the fall of 2020.
These newer strains, according to the World Health Organisation (WHO), are more contagious and could render vaccine and antibody protection less effective and thereby, spread rapidly across dozens of countries in a short span of time.
The WHO has identified three new variants of coronavirus originating in the UK, Brazil and now in South Africa.
Of the three, the latest South African variant known as 20H/501Y.V2 or B.1.351, is different from the one in Britain and appears to be more infectious than the original virus.
This potentially more concerning variant, which has been spotted since December 22 last year and spread to nearly 40 countries including the United States, emerged independently of B.1.1.7 or the UK variant and shares some mutations with the same.
The South African variant carries a mutation called N501Y that appears to make it more contagious or easy to spread, a report in The New York Times said. Also, the WHO has said this variant “is less susceptible to antibody neutralisation” than previous variants.
South African researchers, according to a report in The Wall Street Journal, believe the new strain is around 50 per cent more contagious than the previous variants.
Although the WHO has called for more studies on the new strain, it stressed that observational studies in South Africa did not indicate an increased risk of reinfection.
This South African variant has become a major cause of worry for the scientists because of its unusually large number of mutations, especially in the spike protein, which the virus uses to gain entry into the cells within the human body. Notably, the spike protein is also the part of the virus targeted by Covid-19 vaccines and antibody treatments.
This mutation was also found in the new virus variant that emerged in the UK. However, the WHO noted that while both variants found in the UK and South Africa shared the N501Y mutation, they are different.
Another mutation of the South African variant called E484K, which is not found in the UK strain, is said to help the virus dodge attack by a person’s immune system and hamper the effectiveness of Covid-19 vaccines.
However, there is no evidence that Covid-19 vaccines that have been approved won’t work against the new strain, although results from human clinical trials in South Africa suggest decreased efficiency of these vaccines as against the older variants.