Along with preventing illness and deaths, Covid-19 vaccines may also be curbing the “rampant evolution” of the new coronavirus by limiting new mutations that allow it to evade antibodies, researchers believe.
As part of a larger study, they closely analyzed gene sequences in virus samples obtained from 30 Covid-19 patients who had not been vaccinated and 23 vaccinated individuals with so-called breakthrough cases of Covid-19. In particular, they looked at genes associated with the spike the virus uses to break into cells. The spikes are targeted by the antibodies unleashed by current treatments and vaccines. The more the spike mutates, or changes, the less likely the antibodies will be fully effective.
Compared to virus samples from unvaccinated patients, samples from vaccine breakthrough patients showed significantly fewer mutations on the spike, researchers from data analytics company nference reported on Monday on medRxiv ahead of peer review.
The more people get infected, the more opportunities the virus has to mutate as it makes copies of itself inside the body. It is possible that by suppressing the number of copies made in vaccinated people, the chances to mutate are reduced as well, the authors suggest.
“This study presents the first known evidence that Covid-19 vaccines are fundamentally restricting the … escape pathways accessible to SARS-CoV-2,” they concluded. [Reuters]