Origins of COVID: unanswered questions about the Wuhan epidemic

As the world approaches two years after the first reported cases of COVID-19 in Wuhan, China, we still don’t know much more about the origins of SARS-CoV-2 than we know.

Why is this important: Accurately determining the causes of COVID-19 will go a long way in determining what can and should be done to prevent the next pandemic.

Driving the news: Earlier this week, the Wall Street Journal reported that the WHO is relaunching its stalled investigation into the origins of COVID-19, while a separate academic task force examining the same issue has been disbanded due to concerns about bias.

• At this point, there is no smoking gun in favor of either of the two main theories – that SARS-CoV-2 appeared in animals before spreading to humans, or that it arose out of lab work done at the Wuhan Institute of Virology – but a lot of circumstantial evidence for both.

What they say : On Thursday morning, Science magazine hosted a rare panel discussion 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, evolutionary biologist at the Fred Hutchinson Cancer Center, adding that there is “no high prevalence or natural virus closely related to SARS-CoV-2 in Wuhan. “
• This fact – and the fact that the Wuhan Institute of Virology was working with samples taken from bats that are at high risk of harboring COVID-like coronaviruses – “is why I still believe that a lab leak is highly likely, ”Bloom said.

The other side: Michael Worobey, an evolutionary biologist at the University of Arizona, argued that there were “so many more opportunities for non-research activities to bring these viruses” to Wuhan, such as via China’s strong wildlife trade.

• Political disputes between the United States and China have also made it difficult to fairly judge origins, argued Linfa Wang, a professor at Duke-NUS Medical School in Singapore.
• “You are guilty because you are in Wuhan,” he said. “That’s it.”

The bottom line: As time presses to gather more evidence – and the Chinese government blocks further efforts – the chances of finding a definitive answer diminish.

• But a lesson for the future is clear, as Bloom said: “We need more transparency.”