(CNSNews.com) – Did the coronavirus that emerged in the Chinese city of Wuhan late last year originate from a market where live animals were sold alongside seafood? Or is there another explanation – one that may be linked to China’s leading institute dealing with virology, virus pathology, and emerging infectious diseases?

Debates over the issue have been raging online, even as scientists around the world are, as Science News reported last week, “furiously exchanging data, including genetic details of viruses that have infected people.”

Conspiracy theories birthed by the outbreak of the Wuhan coronavirus, now named COVID-19, include claims of a Chinese bioweapon, deliberately or accidentally discharged.

But with Beijing’s poor record of transparency – in this and previous coronavirus outbreaks – some critics, while not necessarily promoting the notion of a bioweapon, are calling into question the assertion that the Huanan Seafood Wholesale Market was the source.

They are raising questions about a possible link with the Wuhan Institute of Virology (WIV), located less than nine miles away.

Among the reason for this are apparent discrepancies in accounts of the first known COVID-19 infection (“patient zero”).

The Chinese Center for Disease Control and Prevention (CCDC) says the cluster of cases began on December 21.  CCDC researchers reported that three adult patients admitted to hospital on December 27 included one who worked at the seafood market and one who frequently visited the market. (Chinese authorities notified the WHO on December 31, and authorities shut the market on January 1.)

However, according to a paper by two dozen Chinese experts, including the deputy director of Wuhan’s Jinyintan Hospital – published in The Lancet, a leading medical journal – “the symptom onset date of the first patient identified was Dec 1, 2019,” that is, three weeks earlier than the CCDC is saying.

Based on data from the first 41 confirmed COVID-19 patients treated at Jinyintan Hospital, the researchers said, “No epidemiological link was found between the first patient and later cases.”

In other words, “patient zero” had no history of exposure to the seafood market.

Two-thirds of those 41 patients did have exposure to the market, suggesting that the market did indeed serve as an accelerator – but was not necessarily the source – of the virus.

“The virus went into that food market, before it came out of that food market,” Sen. Tom Cotton (R-Ark.) told Fox News on Sunday, pointing to the report in The Lancet.

“So we don’t know where it originated. But we do know that we have to get to the bottom of that,” Cotton said. “We also know that just a few miles away from that food market is China’s only biosafety level-4 super laboratory that researches human infectious diseases.”

“Now, we don’t have evidence that this disease originated there [at the WIV], but because of China’s duplicity and dishonesty from the beginning, we need to at least ask the question to see what the evidence says,” he continued. “And China right now is not giving any evidence on that question at all.”

Bat feces

A second reason for skepticism in some quarters relates to WIV’s research on bats.

Nextstrain.org, an open-source, collaborative scientific initiative tracking the coronavirus, said in its most recent update that while the origin remains unclear, “genomic analysis suggests [COVID-19] is most closely related to viruses previously identified in bats.”

It added that it was plausible other intermediate animal transmissions occurred before the virus was introduced into humans.

Science News reports that genetic mapping being carried out “suggests the new coronavirus is closely related to a bat coronavirus found in China in 2013.”

WIV is China’s specialist lab studying bat and human coronaviruses. In 2013 it collected and mapped a bat coronavirus called RaTG13 from bat feces taken from a cave in China’s Yunnan province.

WIV researchers have themselves reported in recent weeks that COVID-19 shares 96 percent genome sequence identity with RaTG13 from Yunnan.

Three years ago Richard Ebright, a chemistry and chemical biology professor at Rutgers University, was quoted in the journal Nature expressing concern about the security of high-risk viruses at WIV.

Earlier this month, Ebright told the BBC that the bat coronavirus RaTG13 has been stored at the WIV since 2013, and that the possibility of the new outbreak having been caused by a “lab incident” could not be ruled out.

In a Twitter thread on Tuesday, Ebright laid out possible origins of COVID-19, which he said could have occurred either as “a natural accident or as a laboratory accident.”

In one potential scenario, a worker collecting bat samples, or handling bat samples or bat viruses in a lab, could have been infected by the “immediate progenitor of the outbreak virus,” he said. “After brief adaptation to human in patient 0 and possibly others, outbreak occurs.”

The Communist Party-affiliated Global Times daily reported this week that the government’s science ministry has issued new rules requiring laboratories nationwide to tighten their biosafety measures.

It cited a pathogen expert at Wuhan University, Yang Zhanqiu, as saying the release of the guidelines relates to “chronic loopholes at laboratories.”

Yang rejected theories that COVID-19 had “leaked” from the WIV, but did raise concerns about lab procedures in China in general.

“Lab trash can contain man-made viruses, bacteria or microbes with a potentially deadly impact on human beings, animals or plants. Some researchers discharge laboratory materials into the sewer after experiments without a specific biological disposal mechanism, Yang explained,” Global Times reported.