The Boys Who Cried Wolf

Between 1 July and 1 October 2012, we received 13 serum samples collected from 4 patients (one of whom was deceased) who showed severe respiratory disease. These patients had visited a mine cave at Tongguan town, Mojiang County, Yunnan Province, China, to clean bat feces in order to mine copper before being admitted to the First Affiliated Hospital of Kunming Medical University on 26–27 April 2012.

It also stated that:

We suspected that the patients had been infected by an unknown virus. Therefore, we and other groups sampled animals including bats, rats, and musk shrews in or around the cave, and found some alphacoronaviruses1 and paramyxoviruses2. Between 2012 and 2015, our group sampled bats once or twice a year in this cave and collected a total of 1,322 samples.

During these expeditions, the WIV sampled the closest-known bat coronavirus relatives of SARS-CoV-2 including RaTG13, which is 96.2% similar to SARS-CoV-2. To be clear, the RaTG13 and the SARS-CoV-2 viruses diverged more than a decade ago (2003-13 95% HBD limit). This distance in evolution is short enough to indicate that the more proximal ancestors of SARS-CoV-2 likely come from the same geographical region in Yunnan province and the surrounding area where the RaTG13 virus was collected...

We know now from Shi Zhengli's interview with Science that the WIV team sequenced the whole genome in 2018. This reveals interest in SARS-CoV-2-like bat coronaviruses shortly before the pandemic. However, we don't know if they indeed encountered SARS-CoV-2 itself or a closer progenitor than RaTG13 during their expeditions. There is also evidence of Wuhan lab scientists admitting to being bitten by bats and evidence of scientists at the Wuhan CDC not wearing protective equipment or taking proper safety measures during similar expeditions to bat caves. Given what we know about the research at the WIV and the Wuhan CDC and the interest in SARS-CoV-2 like bat coronaviruses shortly before the pandemic, and as SARS-CoV-2 easily loses furin cleavage site when cultured, the most likely route for a lab leak is, therefore, infection of a lab worker during field activity.

So what is the significance of a lab-related leak caused by negligent field workers? It is important to note that although humans outside of laboratories come into contact with animals more frequently than scientists overall, researchers are interested in viruses with human infection potential—and therefore they are much more likely than the average person interacting with animals to come across a bat coronavirus with human infection capabilities. The miners' story provides context that explains why Wuhan scientists were interested in SARS-CoV-2-like bat coronaviruses, and may well have accidentally brought it to a population-dense city and started a global pandemic. If it is confirmed that the pandemic emerged as a result of accidental infection of a lab worker during an expedition, that would raise the question of whether it is a good idea to construct major virology labs in a population-dense city with thousands of people traveling in and out every day.

The U.S. Department of State published a fact sheet in 2020 noting that the U.S. government had reason to believe that workers at the WIV fell sick with symptoms consistent with COVID-19 in the autumn of 2019. Later, it was more specifically revealed that U.S. intelligence identified three lab workers that fell ill in November 2019 and sought hospital treatment.


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