Pandemic mystery: Scientists focus on COVID’s animal origins

Nearly two years into the COVID19 pandemic, the origin of the virus tormenting the world remains shrouded in mystery.

Most scientists believe it emerged in the wild and jumped from bats to humans, either directly or through another animal. Others theorize it escaped from a Chinese lab.

Now, with the global COVID-19 death toll surpassing 5.2 million on the second anniversary of the earliest human cases, a growing chorus of scientists is trying to keep the focus on what they regard as the more plausible “zoonotic,” or animal-to-human, theory, in the hope that what’s learned will help humankind fend off new viruses and variants.

“The lab-leak scenario gets a lot of attention, you know, on places like Twitter,” but “there’s no evidence that this virus was in a lab,” said University of Utah scientist Stephen Goldstein, who with 20 others wrote an article in the journal Cell in August laying out evidence for animal origin.

Michael Worobey, an evolutionary biologist at the University of Arizona who contributed to the article, said he always thought zoonotic transmission was more likely than a lab leak but had signed a letter with other scientists last spring saying both theories were viable. Since then, he said, his own and others’ research has made him even more confident about the animal hypothesis, which is “just way more supported by the data.”

Last month, Worobey published a COVID-19 timeline linking the first known human case to the Huanan Seafood Wholesale Market in Wuhan, China, where live animals were sold.

“The lab leak idea is almost certainly a huge distraction that’s taking focus away from what actually happened,” he said.

Others aren’t so sure. Over the summer, a review ordered by President Joe Biden showed that four U.S. intelligence agencies believed with low confidence that the virus was initially transmitted from an animal to a human, and one agency believed with moderate confidence that the first infection was linked to a lab.

Some supporters of the lab-leak hypothesis have theorized that researchers were accidentally exposed because of inadequate safety practices while working with samples from the wild, or perhaps after creating the virus in the laboratory. U.S. intelligence officials have rejected suspicions China developed the virus as a bioweapon.

The continuing search for answers has inflamed tensions between the U.S. and China, which has accused the U.S. of making it the scapegoat for the disaster. Some experts fear the pandemic’s origins may never be known.