Timeline: How the Wuhan lab-leak theory suddenly became credible

The source of the coronavirus that has left more than 3 million people dead around the world remains a mystery. But in recent months the idea that it emerged from the Wuhan Institute of Virology (WIV) — once dismissed as a ridiculous conspiracy theory — has gained new credence. How and why did this happen? For one, efforts to discover a natural source of the virus have failed. Second, early efforts to spotlight a lab leak often got mixed up with speculation that the virus was deliberately created as a bioweapon. That made it easier for many scientists to dismiss the lab scenario as tin-hat nonsense. But a lack of transparency by China and renewed attention to the activities of the Wuhan lab have led some scientists to say they were too quick to discount a possible link at first.

Sen. Tom Cotton (R-Ark.) from the start pointed to the lab’s location in Wuhan, pressing China for answers, so the history books will reward him if he turns out to be right. The Trump administration also sought to highlight the lab scenario but generally could only point to vague intelligence. The Trump administration’s messaging was often accompanied by anti-Chinese rhetoric that made it easier for skeptics to ignore its claims.

As a reader service, here is a timeline of key events, including important articles, that have led to this reassessment. In some instances, important information was available from the start but was generally ignored. But in other cases, some experts fought against the conventional wisdom and began to build a credible case, rooted in science, that started to change people’s minds. This has led to renewed calls for a real investigation into the lab’s activities before the coronavirus emerged.

In the absence of crucial evidence of how the new coronavirus began comes many theories — one is that the virus accidentally escaped from a lab in Wuhan, China. (Sarah Cahlan, Meg Kelly/The Washington Post)

Early speculation

Dec. 30, 2019: The Wuhan Municipal Health Commission issues an “urgent notice” to medical institutions in Wuhan, saying that cases of pneumonia of unknown cause have emerged from the city’s Huanan Seafood Wholesale Market.

Jan. 5, 2020: Earliest known tweet suggesting China created the virus. @GarboHK tweeted: “18 years ago, #China killed nearly 300 #HongKongers by unreporting #SARS cases, letting Chinese tourists travel around the world, to Asia specifically to spread the virus with bad intention. Today the evil regime strikes again with a new virus.”

Jan. 26: The Washington Times publishes an article with the headline: “Coronavirus may have originated in lab linked to China’s biowarfare program.” An editor’s note is added March 25: “Since this story ran, scientists outside of China have had a chance to study the SARS-CoV-2 virus. They concluded it does not show signs of having been manufactured or purposefully manipulated in a lab.”

Jan. 26: A study by Chinese researchers published in the Lancet of the first 41 hospitalized patients in Wuhan who had confirmed infections found that 13 of the 41 cases, including the first documented case, had no link to the seafood marketplace that originally was considered the origin of the outbreak.

Jan 30: Sen. Tom Cotton, speaking at a Senate Armed Services Committee hearing, says: “This coronavirus is a catastrophe on the scale of Chernobyl for China. But actually, it’s probably worse than Chernobyl, which was localized in its effect. The coronavirus could result in a global pandemic.” He adds: “I would note that Wuhan has China’s only biosafety level-four super laboratory that works with the world’s most deadly pathogens to include, yes, coronavirus.”

Feb. 3: WIV researchers report in the journal Nature that the novel coronavirus spreading around the world was a bat-derived coronavirus. The report said SARS-CoV-2 is 96.2 percent identical at the whole-genome level to a bat coronavirus named RaTG13.

Feb. 6: Botao Xiao, a molecular biomechanics researcher at South China University of Technology, posts a paper stating that “the killer coronavirus probably originated from a laboratory in Wuhan.” He pointed to the previous safety mishaps and the kind of research undertaken at the lab. He withdrew the paper a few weeks later after Chinese authorities insisted no accident had taken place.