As a World Health Organization team delves into the origins of the Covid-19 pandemic, other scientists unearth new captivating clues that suggest the virus behind it has evolved naturally to infect humans.
At least four recent studies have identified coronaviruses closely related to the pandemic strain in bats and pangolins in Southeast Asia and Japan, a sign that these pathogens are more widespread than previously known and that there was a high chance the virus would evolve .
Another new study suggests that a change in a single amino acid in a key component of the virus allowed or at least helped the virus become infectious in humans. Amino acids are organic compounds that form proteins.
Public health officials say it is critical to identify the source of the pandemic to take steps to prevent future outbreaks, although it may take years to do so. These latest investigations add to the evidence that the virus, called SARS-CoV-2, probably originated in bats and then evolved naturally to infect humans, possibly through an intermediate animal.
Studies also help explain why members of a WHO team that completed a four-week mission to Wuhan in February – the Chinese city where the first known cases of Covid-19 were found – are defending the search. of the origin of the pandemic in other countries besides China, in particular those of the border in Southeast Asia.