Caught in crossfire over COVID’s origins
In the early days of the pandemic, scientists reported a reassuring trait in the new coronavirus: It appeared to be very stable. The virus was not mutating very rapidly, making it an easier target for treatments and vaccines. At the time, the slow mutation rate struck one young scientist as odd. “That really made my ears perk up,” said Alina Chan, a post-doctoral fellow at the Broad Institute in Cambridge, Massachusetts. Chan wondered whether the new virus was somehow “pre-adapted” to thrive in humans, before the outbreak even started. “By the time the SARSCoV-2 virus was detected in Wuhan in late 2019, it looked like it had already picked up the mutations it needed to be very good at spreading among humans,” Chan said.
“It was already good to go.”
The hypothesis, widely disputed by other scientists, was the foundation for an explosive paper posted online in May 2020, in which
Chan and her colleagues questioned the prevailing consensus that the lethal virus had naturally spilled over to humans from bats through an intermediary host animal. The question she helped put on the table has not gone away. In late May, President Joe Biden, dissatisfied by an equivocal report he had received on the subject, asked U.S. intelligence services to dig deeper into the origins question. The new report is due any day now. In last year’s paper, Chan and her colleagues speculated that perhaps the virus had crossed over into humans and been circulating undetected for months while accumulating mutations.
Perhaps, they said, the virus was already well adapted to humans while in bats or some other animal. Or maybe it adapted to humans while being studied in a lab, and had accidentally leaked out. Chan found herself in the middle of a maelstrom. An article in a British tabloid, ran with the headline: “Coronavirus did NOT come from animals in the Wuhan market.” Many senior virus experts criticised her work and dismissed it out of hand, saying she didn’t have the expertise to speak on the subject, that she was maligning their specialty and her statements would alienate China, hampering any future investigations.
Some called her a conspiracy theorist. Others dismissed her ideas because she is a post-doctoral fellow, a junior scientist. One virus expert, Benjamin Neuman, called her hypothesis “goofy.” A Chinese news outlet accused her of “filthy behavior and a lack of basic academic ethics,” and readers piled on that she was a “race-traitor,” because of her Chinese ancestry. “There were days and weeks when I was extremely afraid, and many days I didn’t sleep,” Chan, 32, said recently at an outdoor cafe, not far from the Broad Institute.
Chan’s story is a reflection of how deeply polarising questions about the origins of the virus have become. The vast majority of scientists think it originated in bats, and was transmitted to humans through an intermediate host animal, though none has been identified. Some of them believe that a lab accident, specifically at the Wuhan Institute of Virology in China, cannot be discounted and has not been adequately investigated. And a few think that the institute’s research, which involved harvesting bats and bat coronaviruses from the wild, may have played a role.
It is an acrid debate. In May, 18 scientists, including Chan, published a letter calling for an investigation into the origins of the coronavirus. In July, a group of 21 virus experts — including one who had signed the May letter — posted a paper compiling the evidence for an animal source, saying there was “no evidence” of a laboratory origin.
She remains equivocal about the origins of the virus. “I’m leaning toward the lab leak theory now, but there are also days when I seriously consider that it could be from nature,” she said. “On those days, I feel mostly really, really sorry for the scientists who are implicated as possible sources for the virus,” she said. Referring to Shi Zhengli, the top Chinese virus expert who leads the research on emerging infectious diseases at the Wuhan Institute of Virology, Chan said, “I feel really sad for her situation. The stakes could not be higher.”