Renowned Wuhan virologist Shi Zhengli has identified dozens of deadly coronavirus strains in bats over the past decade. Yet, she cautions, these discoveries merely scratch the surface of a vast, hidden threat.
On December 30, while at a conference in Shanghai, Shi Zhengli received an urgent call from her boss. Mysterious patient samples had arrived at the Wuhan Institute of Virology, revealing early signs of a novel coronavirus outbreak.
If confirmed—and given the patients' severe conditions—this pathogen posed a major public health risk. "Drop whatever you're doing and deal with it now," she recalls hearing.
Known as the "bat woman" among peers, Shi Zhengli rushed back to Wuhan on the next flight. Unbeknownst to her, the virus had already begun spreading rapidly. But let's step back to her journey.
For 16 years, Shi Zhengli has led fieldwork studying bats as viral reservoirs. Her work began in 2004 amid the SARS epidemic's aftermath. She joined an international team sampling caves near Nanning, China.
Pre-SARS, coronaviruses were linked mainly to mild colds. SARS changed that, marking the first deadly coronavirus with pandemic potential. Tracing its origins was essential to understanding this emerging threat.
Teams set nets at cave entrances before dusk to capture foraging bats, collecting blood, saliva, and fecal samples.
After eight fruitless months, a nearby lab provided a SARS antibody test kit. Progress was swift: three bat species tested positive. They learned coronaviruses appear seasonally in bats, but antibodies linger for weeks or years.
Refining their search, Shi's team pinpointed Shitou Cave near Kunming, Yunnan. Analyses confirmed it as SARS's origin—and revealed hundreds more coronaviruses. "Most are harmless," Shi explains, "but dozens are SARS-related."
China's wildlife markets, selling bats, civets, and pangolins, are often blamed as viral hotspots. In February 2020, wildlife trade and consumption were banned (except for research or medicine). But that's only part of the picture.
Near Shitou Cave, Shi's 2015 surveys of over 200 villagers found 6% with SARS-like coronavirus antibodies—none had handled bats or shown pneumonia symptoms.
Infection doesn't require wildlife trade or consumption.
Human expansion into wildlife habitats intensifies spillover risks. Reservoirs cluster in specific areas, but global trade and air travel enable rapid spread.
In late 2016, pigs on four Qingyuan farms—near the original SARS site—suffered acute vomiting and diarrhea. Over 25,000 were culled after vets found no known pathogens.
Shi investigated, identifying Swine Acute Diarrhea Syndrome (SADS-CoV), 98% identical to a local bat coronavirus.
Pigs' immune systems mirror humans', easing cross-species jumps. With vast global pig farming and close human-animal contact, Shi stresses: scanning pigs for novel coronaviruses must be a priority.
In Wuhan, the "bat woman" drives ongoing research. "What we've found is just the tip of the iceberg," she says, estimating up to 5,000 undiscovered bat strains worldwide. "Coronaviruses will spark more outbreaks. We must find them before they find us."
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