The Wall Street Journal reports:

On the outskirts of a village deep in the mountains of southwest China, a lone surveillance camera peers down toward a disused copper mine smothered in dense bamboo. As night approaches, bats swoop overhead.

This is the subterranean home of the closest known virus on Earth to the one that causes Covid-19. It is also now a touchpoint for escalating calls for a more thorough probe into whether the pandemic could have stemmed from a Chinese laboratory.

In April 2012, six miners here fell sick with a mysterious illness after entering the mine to clear bat guano. Three of them died.

Chinese scientists from the Wuhan Institute of Virology were called in to investigate and, after taking samples from bats in the mine, identified several new coronaviruses.

Now, unanswered questions about the miners’ illness, the viruses found at the site and the research done with them have elevated into the mainstream an idea once dismissed as a conspiracy theory: that SARS-CoV-2, the virus that causes Covid-19, might have leaked from a lab in Wuhan, the city where the first cases were found in December 2019.

The lab researchers thus far haven’t provided full and prompt answers, and there have been discrepancies in some information they have released. That has led to demands by leading scientists for a deeper investigation into the Wuhan institute and whether the pandemic virus could have been in its labs and escaped.

Even some senior public-health officials who consider that possibility improbable now back the idea of a fuller probe. They say a World Health Organization-led team had insufficient access in Wuhan earlier this year to reach its conclusion that a lab leak was “extremely unlikely.”

Most of those calling for a fuller examination of the lab hypothesis say they aren’t backing it over the main alternative—that the virus spread from animals to humans outside a lab, in the kind of natural spillover that has become more frequent in recent decades. There isn’t yet enough evidence for either idea, they say, nor are the two incompatible. The virus could have been one of natural origin that was brought back to a laboratory in Wuhan—intentionally or accidentally—and escaped.

A growing number, however, including the director-general of the WHO and a prominent U.S. researcher who has worked with the Wuhan Institute of Virology, agree that the WIV needs to provide more information about its work to categorically rule out a lab spill. [Continue reading…]