According to a new study by British scientists from the universities of Bath and Edinburgh, mutations of the virus that causes COVID-19 occur at least once a week - that is, significantly more often than previously thought. An article about this was published in the journal Genome Biology and Evolution.
Viruses mutate regularly, for example when errors accumulate in copying genomes during virus replication. In fact, this is evolution, Darwinian selection. Some mutations of the virus contribute to its survival, while others are harmful to the virus, so strains that acquire such unfortunate mutations quickly go out of the game, scientists do not have time to sequence them.
“Our results mean that if a patient has been sick with covid for more than a few weeks, the virus will have time to evolve, potentially leading to new variants,” explained Professor Lawrence Hirst of the Milner Center for Evolution at the University of Bath. “Usually, most people transmit the virus before it mutates. This means that the likelihood of the evolution of the virus in one patient is not so high."
Previously, it was believed that the SARS-CoV-2 virus, which causes COVID-19, mutates about once every two weeks. However, a new study by the Milner Center for Evolution at the University of Bath and the University of Edinburgh's Department of Human Genetics shows that these estimates did not account for many mutations that actually occurred but were never detected by sequencing. Taking these unaccounted for mutations into account, the group estimated the virus's true mutation rate to be at least 50% higher than previously thought.