THREAD: During 2020-2021, a Pasteur-led team of scientists visited a once-remote area of Feuang District in Laos, located northeast of Vientiane. Amid the remarkable karst jutting into the skies, scientists came closer than anyone else to finding virus that caused COVID-19. It was here we found workers in a cave, knee deep in guano, shovelling it into white bags, which were then lowered down to the ground and eventually spread as fertilizer. A worker here told Reuters they hope to lure more tourists to watch the bats stream out of the cave.

THREAD: I want to tell you a little background of our new series, which dates back to the summer of 2020 when COVID was raging around the world. My colleague Deb Nelson and I started talking about the next one and how to stop it. reuters.com/investigates/s… Deb had been studying the science of zoonotic spillover, the term scientists use to describe when a human is infected by a virus circulating among wildlife. Scientists were increasingly linking these spillovers to habitat disruption — tree loss, agricultural intensification, etc