Bats in Laos Caves Harbor Closest Relatives to Covid-19 Virus

HKDU⠀ Published at 2021-10-19

Researchers at France’s Pasteur Institute and the University of Laos looked for viruses similar to the one that causes Covid among hundreds of horseshoe bats. They found three with closely matched receptor binding domains -- the part of the coronavirus’s spike protein used to bind to human ACE-2, the enzyme it targets to cause an infection.

The finding, reported in a paper released Friday that’s under consideration for publication by a Nature journal, shows that viruses closely related to SARS-CoV-2 exist in nature, including in several Rhinolophus, or horseshoe bat, species. The research supports the hypothesis that the pandemic began from a spillover of a bat-borne virus. About 1,000 such infections may be occurring daily in southern China and Southeast Asia in areas with dense populations of bats from the Rhinolophus genus, a study Tuesday found. 

The three viruses found in Laos, dubbed BANAL-52, BANAL-103, and BANAL-236, are “the closest ancestors of SARS-CoV-2 known to date,” said Marc Eloit, head of pathogen discovery at the Pasteur Institute in Paris, and co-authors. “These viruses may have contributed to SARS-CoV-2’s origin and may intrinsically pose a future risk of direct transmission to humans.”