Coronavirus adapting to humans with mutations that could help it spread, scientists fear

‘A major challenge to defeating viruses is that a vaccine or drug might no longer be effective if the virus has mutated’

Scientists have discovered coronavirus is adapting to humans with mutations that could help it spread quicker.

After analysing more than 5,300 whole genome sequences of the new coronavirus from 62 countries, researchers found several mutations that show the virus is “well adapted” to humans.

Significantly, the team, from London School of Hygiene and Tropical Medicine, identified a “potentially critical mutation” to the “spike protein” the virus uses to infect human cells.

It is not uncommon for viruses to mutate, however researchers are concerned the mutations seen in this virus could be giving it an advantage since they have occurred independently in 62 different countries.

The team behind the study fear the mutations have given the virus an improved ability for human transmission, and that they could impact whether vaccines or drugs being developed will work to kill it.

However they stressed mutations at this stage are still rare, and that it is not yet known how the changes will affect the coronavirus.

Professor Martin Hibberd, a senior author of the study, which has not been peer reviewed and is unpublished, said: “Overall, the virus does not seem to have mutated very much and most strains are relatively similar to each other.

“This suggests that the virus is well adapted to humans and is not changing rapidly.

“However, while the number of genetic variations at this stage of the pandemic were relatively small, we have seen a few that look important to the virus and these could have important implications for diagnostics, vaccines and therapies.”

The study also identified two main strains of coronavirus across the globe, which had different prevalence in individual countries.

It stated the Sars-Cov-2 coronavirus that causes Covid-19 most likely evolved from a bat beta-coronavirus and started infecting humans in December 2019.

A separate study, led by University College of London (UCL) Genetics Institute, also identified 198 recurrent genetic mutations in the new coronavirus after analysing genomes from more than 7,500 people infected with Covid-19.

The findings, published in the journal Infection, Genetics and Evolution, add to a growing body of evidence that Sars-Cov-2 viruses share a common ancestor from late 2019, suggesting that this was when the virus jumped from a previous animal host into people.

This means it is unlikely the virus causing Covid-19 was in human circulation for long before it was first detected.

In many countries, including the UK, the diversity of viruses sampled was almost as much as that seen across the whole world, meaning the virus entered the UK numerous times independently, rather than through any one index case.

Professor Francois Balloux, co-lead author from UCL Genetics Institute, said: “All viruses naturally mutate.

“Mutations in themselves are not a bad thing and there is nothing to suggest Sars-Cov-2 is mutating faster or slower than expected.

“So far we cannot say whether Sars-Cov-2 is becoming more or less lethal and contagious.”

However he added: “A major challenge to defeating viruses is that a vaccine or drug might no longer be effective if the virus has mutated.

“If we focus our efforts on parts of the virus that are less likely to mutate, we have a better chance of developing drugs that will be effective in the long run.”