[ad_1]
Scientists say they have identified a new variant of SARS-CoV-2 – the virus that causes COVID-19 – in the United States, it is perhaps the most dominant form in the country.
The variant – called 20C-US – appears to have taken root in the southern part of the country in late spring and early summer 2020, with researchers tracing its first appearance in Texas in May, according to a study submitted on the pre– printer server bioRxiv.
The document is a preliminary report which has not yet been peer reviewed and therefore should not be considered conclusive. But scientists at Southern Illinois University (SIU) wrote in the study that the variant had “probably … become the most dominant variant in the United States”
“It’s here. We found it,” Keith Gagnon, author of the study by SIU‘s School of Medicine, said in a statement. “It’s really local and widespread, and we’re the first to characterize it.”
The variant does not appear to have spread widely beyond the United States, although it has also been detected at very low levels in a handful of other countries including Mexico, Australia, New Zealand. Zealand, Singapore, Thailand, Taiwan, Poland and Israel, the researchers told me.
In the United States, it appears to be most prevalent in the Upper Midwest, the team found in its analysis, noting that 20C-US is expected to continue to spread across the country.
Scientists have yet to determine whether the variant is more transmissible than others. But Gagnon and his team say the rise of 20C-US coincides with the second and third wave of COVID infections in the United States – circumstantial evidence that it may be more infectious than other variants.
“There are hundreds of variations floating around, so for this one to gain prominence suggests it might be more heritable,” Gagnon said.
The rise of the variant also coincides with a substantial reduction in case fatality rates in the United States despite the recent increase in cases. While many factors contribute to case fatality rates, scientists say in the study that it is “plausible that 20C-US represents SARS-CoV-2 variant with more transmissibility but a milder disease. “
“Such variants could in theory generate a fitness advantage for the virus because they are more likely to spread quietly,” the authors wrote.
Like SARS-CoV-2 has spread around the world, the virus has undergone genetic mutations which have led to the emergence of several new variants. The new mutations are not always beneficial for the virus, but in some cases they significantly alter its characteristics.
New variants that were recently detected in the UK and South Africa, for example, appear to be more transmissible than the original.
Daniel Davis, professor of immunology at the University of Manchester in the UK, who was not involved in the research, said Newsweek: “As more and more samples of this virus are genetically analyzed, we understand much better how the virus varies across the world. Variation is to be expected and not alarming per se. It is well established that different versions of viruses appear, and fall over time. “
“This new variant, dubbed 20C-US, is now known to be one of the common versions of the virus found in the United States, but there are still many other versions of the virus circulating in the United States.”
It is also currently unclear whether the genetic changes present in the new American variant will or will not affect the effectiveness of COVID-19 vaccines, although Gagnon said there likely won’t be any significant impact at this time.
“Based on the mutations so far, I don’t think it will have a significant impact on the effectiveness of the vaccine. The catch is that the virus continues to evolve, and since May it has acquired three mutations, including two in the spike protein, one of which could affect antibody binding. There is a lot of unknown. “
The spike protein, located on the outside of the virus, allows it to bind and enter human cells.
Ian Jones, professor of virology at the British University of Reading, said Newsweek there is currently no reason to suggest that the vaccine will not be effective against the new variant or that it causes more serious disease.
“This is yet another example of the COVID virus adapting to the human population, “he said.” In this case, the suggested key mutation may not change the binding of the virus to the cell but the entry step immediately following it, just as effective for increased transmission. “
iStock
[ad_2]
Source link