Unanswered questions about COVID's origins
As the world nears two years after the first reported cases of COVID-19 in Wuhan, China, there's still a lot more we don't know about SARS-CoV-2's origins than we do know.
Why it matters: Accurately determining the causes of COVID-19 will go a long way toward informing what can and should be done to prevent the next pandemic.
Driving the news: Earlier this week, the Wall Street Journal reported the WHO is reviving its stalled investigation into the origins of COVID-19, while a separate academic task force looking into the same question was disbanded over concerns about bias.
- At this point, there is no smoking gun in favor of either of the two main theories — that SARS-CoV-2 emerged in animals before spreading to people, or that it originated in lab work done at the Wuhan Institute of Virology — but plenty of circumstantial evidence for both.
What they're saying: On Thursday morning, Science magazine convened a rare roundtable featuring scientists from both sides of the debate.
- A major problem is "we can't really say how the virus got to Wuhan," said Jesse Bloom, an evolutionary biologist at the Fred Hutchinson Cancer Center, adding there is "not a high, or any natural prevalence of viruses closely related to SARS-CoV-2 in Wuhan."
- That fact — and that the Wuhan Institute of Virology was working with samples taken from bats that have a high risk of harboring COVID-like coronaviruses — "is why I continue to think a lab leak is highly probable," Bloom said.
The other side: Michael Worobey, an evolutionary biologist at the University of Arizona, argued there were "so many more opportunities for non-research-connected activity to bring these viruses" to Wuhan, such as via China's robust wildlife trade.
- The political disputes between the U.S. and China have also made it hard to fairly judge the origins, argued Linfa Wang, a professor at Duke-NUS Medical School in Singapore.
- "You're guilty because you're in Wuhan," he said. "That's it."
The bottom line: With time running out to gather more evidence — and the Chinese government stonewalling further efforts — the chance of finding a definitive answer is dwindling.
- But one lesson for the future is clear, as Bloom put it: "We need more transparency."