Coronavirus mutations do not make Covid spread rapidly, according to a study from University College London.
The global study, which probed over 12,000 coronavirus mutations, suggests that mutations all appeared to be neutral when it comes to accelerating the spread of the virus. The researchers evaluated over 46,000 samples taken from people in 99 different countries.
Published in the Nature Communications journal, the peer-reviewed study examined a total of 12,706 mutations. Of those, 398 strains of the coronavirus appeared to have occurred repeatedly and independently.
The team focused on 185 mutations which had taken place at least three times independently during the course of the pandemic.
“Recurrent mutations currently in circulation appear to be evolutionary neutral and primarily induced by the human immune system via RNA editing, rather than being signatures of adaptation,” researchers of the study said.
“At this stage we find no evidence for significantly more transmissible lineages of SARS-CoV-2 due to recurrent mutations,” they added.
Findings come as drugmakers and research centers speed up the development of a safe and effective vaccine to help control the pandemic.
“Mutations that are fairly common all seem neutral for the virus carrying them. This includes D614G, which according to our analysis is more of a stowaway that got a lucky ride on a successful lineage, rather than a driver of transmission,” said Professor Francois Balloux, director of UCL Genetics Institute and one of the study’s authors.
“This raises the question why #SARSCoV2 is so well adapted for transmission in humans. A plausible answer is that we missed the early window when it adapted to humans,” Balloux said via Twitter on Wednesday.
Coronavirus mutations
The study shows "the virus is mutating due to a combination of neutral drift -- which just means random genetic changes that don't help or hurt the virus -- and pressure from our immune systems," said Ilya Finkelstein, associate professor of molecular biosciences at The University of Texas at Austin and co-author of the study.
"The virus continues to mutate as it rips through the world," Finkelstein said. "Real-time surveillance efforts like our study will ensure that global vaccines and therapeutics are always one step ahead."
Pharmaceutical giant Pfizer previously announced that the final analysis of the Phase 3 trial of its coronavirus vaccine showed 95% effectiveness in preventing infections.
In the trial, Pfizer discovered 170 cases of coronavirus infection among volunteers, 162 of which were in people who received placebo or plain saline shots while the remaining 8 cases were from participants who received the BNT162b2 vaccine.
In a joint statement, Pfizer and its German partner BioNTech said: “Efficacy was consistent across age, race and ethnicity demographics. The observed efficacy in adults over 65 years of age was over 94%.”
The companies continued: “There were 10 severe cases of Covid-19 observed in the trial, with nine of the cases occurring in the placebo group and one in the BNT162b2 vaccinated group.”
Moreover, Moderna's vaccine is 94.5% effective based on early data results. The company will apply for approval to use the vaccine.
Moderna's trial involved 30,000 participants in the U.S. with half being given two doses of the vaccine, four weeks apart. The rest took dummy injections. The analysis was taken from the first 95 to manifest Covid-19 symptoms.
Only five of the coronavirus cases were in people given the vaccine while 90 were in those who received the dummy treatment. The company noted that the vaccine is protecting 94.5% of people.
