Naturally, the coronavirus mutates as it spreads. But scientists are more concerned with some mutations than others, and there is one in particular that is of concern because it may affect the vaccine’s effectiveness in the future.
Specifically, the 20C / 501Y.V2 variant – also known as strain B.1.351 – which has emerged in Durban, South Africa, is alarming because the virus mutation is at the peak of SARS-CoV-2, disguising its appearance to the immune system, which can make it easier to bypass immune protection. Think of it as someone putting on a wig to go to a party to which he was not invited and deceiving the security guard by changing his appearance to enter.
“The concern is that there is a structural change that can alter the shape of the Spike protein so that it is not so easily recognized by the immune system, which means that the antibodies we create through vaccination, as well as antibodies naturally occur after a next infection, “explained Dr. George Rutherford, professor of epidemiology at the University of California, San Francisco.” That’s the concern with this strain. “
Dean Blumberg, head of pediatric infectious diseases and an associate professor in the Department of Pediatrics at the University of California, Davis, agrees.
“We need to be immune to this peak protein to prevent infection. If it changes, if it mutates a lot, we may be able to lose the immunity we achieve through infection or immunization,” said Blumberg.
The 501Y.V2 variant is believed to be behind a fast-growing coronavirus outbreak in the Eastern Cape Province in South Africa. Researchers first identified the variant in October 2020 in Nelson Mandela Bay, South Africa In December 2020, it was also identified in Zambia and appeared to be the dominant strain in the country. According to preliminary strain data, the variant samples carry up to 9 changes in the peak protein. A 501Y.V2 mutation that is of concern is N501Y because of how the peak part is mutated. A second mutation, called E484K, appears to have altered the shape of the protein in a way that is making it difficult for some antibodies to neutralize the virus.
“There are preliminary studies that suggest that people who have been infected with previous strains can neutralize the virus up to 10 times less,” said Blumberg. “So this is a real concern, and it suggests that perhaps vaccine-induced immunity can be prevented by this new variant in South Africa.”
Indeed, A paper published on this specific mutation this week echoed those concerns. An article author said STAT News that despite the findings that the virus was more difficult to neutralize with antibodies from other strains, the variant would have to have very specific mutations at certain points to have a major impact on the vaccine’s effectiveness.
According to a report published this week, scientists tested Pfizer’s N501Y vaccine using blood samples from 20 people. Fortunately, the vaccination worked for them, but the sample size was too small to say definitively that it would be true for the general population.
Does this reinforce the hypothesis that the COVID-19 vaccines will be similar to the flu vaccine, in the sense that they will be adapted for different strains and more frequent?
“Maybe, maybe not,” said Rutherford. “But it would be quite unusual if we had to move in and change so quickly.”
The Center for Disease and Control (CDC) warned that the potential consequence of these mutations could be that these variants could escape the vaccine’s immunity, but would not have an immediate impact.
“Both vaccination against natural infection and SARS-CoV-2 produce a ‘polyclonal response; it targets various parts of the spike protein,” says the CDC. “The virus would probably need to accumulate multiple mutations in the spike protein to escape immunity induced by vaccines or by natural infection.”
Masking and social detachment still work to protect people of that lineage, which has not yet been identified in the United States. According to the BBC, it has been identified in Austria, Norway and Japan. Notably, there is no evidence to suggest that any of the mutations in this variant cause more serious illnesses.
“Currently, there is no evidence that these variants cause more serious illness or increase the risk of death,” says the CDC. “New information on the virological, epidemiological and clinical characteristics of these variants is rapidly emerging.”