How China’s “Bat Woman” Hunted Down Viruses from SARS to the New Coronavirus
Shi Zhengli, known as China’s “bat woman” for her virus-hunting expeditions in bat caves, releases a fruit bat after taking blood and swab samples from it. Credit: Wuhan Institute of Virology
Shi—a virologist who is often called China’s “bat woman” by her colleagues because of her virus-hunting expeditions in bat caves over the past 16 years—walked out of the conference she was attending in Shanghai and hopped on the next train back to Wuhan. “I wondered if [the municipal health authority] got it wrong,” she says. “I had never expected this kind of thing to happen in Wuhan, in central China.” Her studies had shown that the southern, subtropical areas of Guangdong, Guangxi and Yunnan have the greatest risk of coronaviruses jumping to humans from animals—particularly bats, a known reservoir for many viruses. If coronaviruses were the culprit, she remembers thinking, “could they have come from our lab?”
By January 7 the Wuhan team determined that the new virus had indeed caused the disease those patients suffered—a conclusion based on results from polymerase chain reaction analysis, full genome sequencing, antibody tests of blood samples and the virus’s ability to infect human lung cells in a petri dish. The genomic sequence of the virus—now officially called SARS-CoV-2 because it is related to the SARS pathogen—was 96 percent identical to that of a coronavirus the researchers had identified in horseshoe bats in Yunnan, they reported in a paper published last month in Nature. “It’s crystal clear that bats, once again, are the natural reservoir,” says Daszak, who was not involved in the study.
“The SARS outbreak was a game changer,” says Wang, whose work on bat-borne coronaviruses got a swift mention in the 2011 Hollywood blockbuster Contagion. It was the first time a deadly coronavirus with pandemic potential emerged. This discovery helped to jump-start a global search for animal viruses that could find their way into humans.
Samples from three horseshoe bat species contained antibodies against the SARS virus. “It was a turning point for the project,” Shi says.
one spot: Shitou Cave on the outskirts of Kunming, the capital of Yunnan—where they conducted intense sampling during different seasons throughout five consecutive years.
The efforts paid off. The pathogen hunters discovered hundreds of bat-borne coronaviruses with incredible genetic diversity. “The majority of them are harmless,” Shi says. But dozens belong to the same group as SARS. They can infect human lung cells in a petri dish, cause SARS-like diseases in mice, and evade vaccines and drugs that work against SARS.
In Shitou Cave—where painstaking scrutiny has yielded a natural genetic library of bat viruses—the team discovered a coronavirus strain in 2013 that came from horseshoe bats and had a genomic sequence that was 97 percent identical to the one found in civets in Guangdong. The finding concluded a decade-long search for the natural reservoir of the SARS coronavirus.
Yunnan’s mountainous Mojiang Hani Autonomous County
Pu’er City, Yunnan China
famous for its fermented Pu’er tea
Severe acute respiratory syndrome coronavirus (SARS-CoV) is the causative agent of the 2002–2003 SARS pandemic, which resulted in more than 8000 human infections worldwide and an approximately 10% fatality rate
“you don’t need to be a wildlife trader to be infected.”
After sampling the cave for a year the researchers discovered a diverse group of coronaviruses in six bat species. “Bat guano, covered in fungus, littered the cave.” Although the fungus turned out to be the pathogen that had sickened the miners, she says it would only have been a matter of time before they caught the coronaviruses if the mine had not been promptly shut.