As the British coronavirus variant occupies the countries’ pandemic plans due to its increased portability, other mutations in Sars-CoV-2 are causing concern among scientists struggling to find out if they will still respond to the vaccines.
In particular, a mutation known as E484K, originally discovered in South Africa and later in Brazil and Japan, has caused concern among researchers.
Ravi Gupta, a professor of microbiology at the University of Cambridge, said it was this mutation ̵
Although research on the new variant is limited, a Brazilian study this month looked at a patient who had recovered from Covid-19 only to be reinfected with the new, mutated strain.
The paper has yet to be reviewed, but the authors have found that the E484K mutation may be “associated with an escape from neutralizing antibodies” – meaning it can bypass the body’s natural immune defenses.
As countries accelerate their vaccination programs, there are fears that the new mutation may make some vaccines less effective.
The Pfizer and Moderna vaccine, for example, uses mRNA technology to instruct the body to produce a harmless coronavirus protein that the immune system then learns to kill in anticipation of a true infection.
With E484K, as with the British version, the mutation occurs on the virus’s protein, which allows it to bind more easily to human cell receptors, potentially increasing its infectivity.
Gupta said the mutation “could be the beginning of problems with spike vaccines.”
“They all need to be effective right now, but we are worried about further mutations occurring on those,” he told AFP.
– “Bypass current protection” –
Pfizer and German partner BioNTech said last week that their vaccine was effective against the N501Y mutation, found in a variant of the British virus known as B117.
Francois Balu, a professor of computer systems biology and director of the Institute of Genetics at University College London, said the South African version was unlikely to mutate enough to “bypass the protection provided by current vaccines”.
But he warned: “The E484K mutation has been shown to reduce antibody recognition.
“As such, it helps the Sars-CoV-2 virus bypass the immune protection provided by pre-infection or vaccination,” Balu said.
There have been several mutations in the new coronavirus since its appearance in late 2019, and most have had a negligible effect on its transmission or severity.
However, the British version shows in several studies that it is up to 70 percent more contagious than normal viral strains.
And the South African version seems more effective in avoiding the body’s natural reaction.
– New vaccines? –
A pre-press study in December concluded that the two new variants showed that Sars-CoV-2 “has the potential to avoid an effective immune response.”
The researchers investigated what happened to the virus when it was left in contact with plasma taken from a patient who had recovered from Covid-19.
Within three months, the virus acquired several mutations, including E484K.
The authors suggest that “vaccines and antibodies capable of controlling emerging variants should be developed.”
Lead researcher Reno Rapuoli, an immunologist with pharmaceutical giant GlaxoSmithKline, told AFP that current mutations in protein mutations should not be a problem for existing vaccines.
And even if the virus mutates to better avoid the immune response, vaccines must provide at least some level of effective immunity.
“Even if you reduce efficiency, there will usually be some neutralization of the virus,” Vincent Enuf of the Paris Pasteur Institute told AFP.
To be safe, Gupta advocated an accelerated vaccination program, providing as much immunity as current vaccines can deliver “as quickly as possible around the world.”
© 2021 AFP