As a deadly new virus starts spreading in Wuhan, China, so do rumours about a lab there.

In the remote, jungle-covered hills of China’s far-southwestern Yunnan Province, teams of scientists have spent years intensively researching one animal: bats. The scientists are virus hunters, trying to better understand and mitigate the threat of new viruses jumping from bats to other animals and humans, potentially setting off a pandemic. Their samples of bat droppings are brought back to labs, including the Wuhan Institute of Virology. So when a new coronavirus begins killing people in that same city, questions are raised about whether the people trying to stop a pandemic could’ve accidentally triggered one.

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