New COVID-19 strain spreads faster in US than previous variants

“It might be more easily transmissible than other variants, and its impact on vaccines is uncertain” – study • same mutation may be occurring independently around the world

An image of the virus that causes COVID-19, created by the CDC (photo credit: Courtesy)
An image of the virus that causes COVID-19, created by the CDC
(photo credit: Courtesy)
A new variant of the coronavirus was discovered in the United States, and seems to be even more contagious than both the South African and British strain previously discovered throughout the US, two studies revealed.
In the first study, scientists from Southern Illinois University identified a third US variant of COVID-19, that may be the most contagious strain in the US yet, researchers said Thursday, adding it is believed to be responsible for up to 50% of all US cases. The spreading speed referred specifically to the cases throughout the US.
“It’s here. We found it,” said Keith Gagnon, an associate professor of biochemistry at SIU Carbondale who discovered the new variant, referred to as 20C-US.
 
“It’s definitely home-grown and widespread, and we’re the first to characterize it,” Gagnon said, adding that its impact on vaccines is uncertain.
The homegrown mutation is hitting mostly the Midwest, researchers said in a press release, revealing that they traced the strain back to Texas, where it apparently first appeared in May. 
“We have identified a new variant of the SARS-CoV-2 virus that emerged in the United States early in the coronavirus disease pandemic and has become one of the most prevalent US variants,” the release states. “It might be more easily transmissible than other variants, and its impact on vaccines is uncertain.”
These findings were revealed a day after scientists from Ohio State University's Wexner Medical Center and College of Medicine discovered the new variant of SARS-Cov-2, identical to the UK strain, but likely arising in a virus strain already present in the United States. 
The researchers also reported the evolution of another US strain, 20C-US, which acquired three other gene mutations not previously seen together in SARS-CoV-2.
The results of the 20C-US study were published on Wednesday in the a non-peer-reviewed online journal bioRxiv.org, meaning that further investigation is needed.
“The big question is whether these mutations will render vaccines and current therapeutic approaches less effective,” said study co-author Peter Mohler, chief scientific officer at the Wexner Medical Center and vice dean for research at the College of Medicine. “At this point, we have no data to believe that these mutations will have any impact on the effectiveness of vaccines now in use.
“It’s important that we don’t overreact to this new variant until we obtain additional data,” Mohler said. “We need to understand the impact of mutations on transmission of the virus, the prevalence of the strain in the population and whether it has a more significant impact on human health. 
"Further, it is critical that we continue to monitor the evolution of the virus, so we can understand the impact of the mutant forms on the design of both diagnostics and therapeutics," he said. "It is critical that we make decisions based on the best science.” 
The scientists said that discovery of the Columbus variant, COH.20G/501Y, suggests that the same mutation may be occurring independently in multiple parts of the world during the past few months.
“Viruses naturally mutate and evolve over time, but the changes seen in the last two months have been more prominent than in the first months of the pandemic,” Jones said. His team has been conducting Ohio State’s genetic sequencing on environmental and patient SARS-CoV2 samples, and he’ll continue to monitor for changes as vaccination occurs. 
The Centers for Disease Control and Prevention said last week that it had not seen the emergence of a highly contagious new US variant of the coronavirus. It noted, however, that there are probably many variants emerging around the globe.