Understanding the origin of SARS-CoV-2, the virus that causes COVID-19, is very important. It might tell us something about an infection that has killed 4 million people in 18 months and left millions of others suffering from long COVID. It might also help us stave off future pandemics.
A new critical review preprint paper (not yet peer-reviewed) on the origin of SARS-CoV-2 has been published that overwhelmingly supports the evidence the virus transferred from an animal to humans and states that there is zero biological evidence to support the “lab leak hypothesis”. Authored by an international team of leading biologists from universities and research institutes around the world, they warn that not focusing inquiry on the zoonotic origin will leave us "vulnerable to future pandemics”.
“Our careful and critical analysis of the currently available data provided no evidence for the idea that SARS-CoV-2 originated in a laboratory,” lead author Professor Edward Holmes from the University of Sydney said in a statement.
The authors critically reviewed the scientific evidence and available data on the virus so far, looked at the contagions in Wuhan, and compared the novel coronavirus with the first SARS virus from 2003. While the animal host from which SARS-CoV-2 originated has yet to be identified, all the biological evidence matches a zoonotic event: the virus jumped from an animal to humans.
“There is no evidence that any early cases had any connection to the Wuhan Institute of Virology (WIV), in contrast to the clear epidemiological links to animal markets in Wuhan, nor evidence that the WIV possessed or worked on a progenitor of SARS-CoV-2 prior to the pandemic,” the paper reads.
The idea that the virus came from a lab became has been discussed as a fringe idea for most of the pandemic but it had a resurgence in the last few months with influential voices on social media lending credit to it. Not having found the original animal host for this virus makes it impossible to exclude an accidental leak or a purposeful release of the virus from a lab. That being said, extraordinary claims require extraordinary evidence, and currently there is no evidence supporting the lab leak theory, while there is plentiful evidence of zoonotic origin.
“This manuscript represents a very considered review of all virological and epidemiological evidence regarding the origins of the cause of the COVID-19 pandemic, SARS-COV-2. The authors, who are acknowledged experts in their fields, concluded that there is a substantial body of scientific evidence supporting a zoonotic origin for SARS-CoV-2,” Prof James Wood of the University of Cambridge, who was not involved in the study, commented.
“The debate about the origins of SARS-CoV-2 is becoming increasingly acrimonious. The failure to detect a potential natural host has stimulated suggestions by some that the COVID-19 pandemic has resulted from the escape of an engineered virus from a lab in Wuhan, China. However, there is little or no evidence for such an event and lab leak theories remain essentially speculative, at times verging on conspiratorial,” added Dr Jonathan Stoye of The Francis Crick Institute, who also wasn’t involved in the study.
“By contrast, the current preprint provides a refreshingly clear and reasoned description of the virological events that have taken place during the emergence of the pandemic virus. It makes a strong case for the natural origin of the virus followed by on-going adaptation in humans."
While not ruling out other possibilities, focusing on a theory with no evidence to back it up distracts from working on what we do know about SARS-CoV-2, COVID-19 and how to prevent future pandemics.