Covid mutations don’t appear to help virus spread faster, study finds

LONDON – A global study of more than 12,000 coronavirus mutations has found that none of them appear to have caused the virus that causes Covid-19 to spread faster.

Researchers at University College London evaluated Covid mutations in more than 46,000 samples taken from people in 99 different countries and concluded that the mutations all appeared neutral to speed up the spread of the virus.

The peer-reviewed study, published Wednesday in the journal Nature Communications, identified a total of 12,706 mutations. Of these, 398 strains of the coronavirus have occurred repeatedly and independently.

The researchers decided to focus on 185 mutations that had occurred at least three times independently during the pandemic.

“The recurrent mutations currently circulating appear to be evolutionarily neutral and primarily induced by the human immune system via RNA editing, rather than being adaptive signatures,” the study researchers said. .

“At this point, we find no evidence of significantly more transmissible lines of SARS-CoV-2 due to recurrent mutations,” they added.

The study results come as drugmakers and research centers strive to provide a safe and effective vaccine to help end the coronavirus pandemic.

British pharmaceutical giant AstraZeneca said on Monday that an interim analysis showed its vaccine against the coronavirus to have an average effectiveness of 70%. This news follows good results from Pfizer-BioNTech and Moderna regarding the efficacy of each of their candidate vaccines.

Viruses mutate naturally, and scientists have previously said they observed minor mutations in the coronavirus that did not have a significant impact on its ability to spread or cause disease.

However, earlier this year, a much-discussed mutant variant of the coronavirus known as D614G was believed to improve viral transmission. This prompted White House coronavirus adviser Dr Anthony Fauci to warn that the newly discovered variant could help the pathogen to spread more easily.

“The mutations that are fairly common all appear to be neutral to the virus that carries them. This includes D614G, which, according to our analysis, is more of a stowaway who has had the chance to take a ride on a successful lineage, rather than a transmission motor, ”said Professor François Balloux, director of the UCL Genetics Institute and one of the study’s authors.

“This raises the question of why # SARSCoV2 is so well suited for transmission in humans. A plausible answer is that we missed the first window when it adapted to humans,” Balloux said via Twitter on Wednesday.

To date, more than 60.5 million people have contracted the coronavirus, with 1.4 million related deaths, according to data compiled by Johns Hopkins University.