Novel coronavirus not lab-made and may have been in humans for years: Study
The study, party supported by the US National institute of Health also debunks the suggestion that the novel coronavirus that causes COVID-19 could have been created in a laboratory.
As the coronavirus pandemic continues to wreak havoc across the world - infecting millions and killing thousands, a group of scientists has discovered that the SARS-CoV-2 or novel Coronavirus could have been transmitted among humans years or even decades before the Wuhan outbreak in November 2019.
According to findings published in the journal Nature Medicine, the virus could have possibly been transmitted from animals to humans much before its first detection in Wuhan, China.
The study1, which was conducted by an international team of scientists from Australia, Britain and the US, was released on March 17 in the scientific journal. It analyses publicly available genomic data to ascertain the origins of SARS-CoV-2 or novel coronavirus which causes COVID-19.
The study, party supported by the US National institute of Health, was conducted by Kristian Andersen from the Scripps Research Institute in California, Andrew Rambaut from the University of Edinburgh in Scotland, Ian Lipkin from Columbia University in New York, Edward Holmes from the University of Sydney, and Robert Garry from Tulane University in New Orleans.
The study first of all debunks the theory that the new coronavirus causing the pandemic was engineered in a lab and deliberately released to make people sick. By comparative analysis of genomic that the study it establishes that the coronavirus that causes COVID-19 almost certainly originated in nature.
Then the researchers arrive at two theories to explain the natural origin of SARS-CoV-2. The first scenario is that the novel coronavirus evolved in its natural hosts, possibly bats or pangolins and gained the infectious edge there.
The second scenario is that the new coronavirus crossed from animals into humans before it became capable of causing human disease. "Then, as a result of gradual evolutionary changes over years or perhaps decades, the virus eventually gained the ability to spread from human-to-human and cause serious, often life-threatening disease," Dr Francis Collins, director of the US National Institute of Health, said in an article published on the institute’s website.
According to the second scenario the new coronavirus might have gained its ability to infect people (marked by acquisition of the polybasic cleavage site) through "unrecognized transmission in humans over an extended period."
Earlier, Professor Remuzzi, Director of the Mario Negri Institute for Pharmacological Research in Milan had said that he would not be surprised if some asymptomatic carriers had travelled around China or even abroad before December last year. He had said, "It means that the virus was circulating at least in Lombardy (Italian region) before we were aware of this outbreak occurring in China."
1. Andersen, K.G., Rambaut, A., Lipkin, W.I. et al. The proximal origin of SARS-CoV-2. Nat Med (2020). https://doi.org/10.1038/s41591-020-0820-9