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

LONDON – A global study of over 12,000 coronavirus mutations found that none of them appear to have made the virus that causes Covid-19 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 seemed neutral when it came to accelerating 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 occurred repeatedly and independently.

The researchers set out to investigate 185 mutations that had occurred at least three times independently during the course of the pandemic.

“The recurrent mutations currently in circulation appear to be evolutionary neutral and primarily induced by the human immune system via RNA editing, rather than being signs of adaptation,” the study researchers said.

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

The study results come as drug makers and research centers scramble to deliver a safe and effective vaccine to help end the coronavirus pandemic.

British pharmaceutical giant AstraZeneca said on Monday that an interim analysis showed that its coronavirus vaccine has an average efficacy of 70%. The news followed excellent results from Pfizer-BioNTech and Moderna regarding the effectiveness of each of their vaccine candidates.

Viruses mutate naturally, and scientists have previously claimed to have observed minor mutations in the coronavirus that did not affect its ability to spread or cause disease in any significant way.

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

“The mutations that are fairly common all appear neutral to the virus that carries them. This includes D614G, which according to our analysis is more of a stowaway who got lucky on a successful lineage, rather than a factor of transmission,” he said. Professor Francois Balloux, director of the UCL Genetics Institute and one of the authors of the study.

“This raises the question of why # SARSCoV2 is so well adapted for transmission in humans. A plausible answer is that we missed the initial 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 collected by Johns Hopkins University.