Speculation is still swirling around how and when the coronavirus began to spread in Wuhan and China is currently investigating the issue. But a representative for the World Health Organization (WHO) told Sky News Thursday that China has refused its requests to participate in that investigation.

“We know that some national investigation is happening but at this stage we have not been invited to join,” Dr Gauden Galea said.

“WHO is making requests of the health commission and of the authorities,” he said. “The origins of virus are very important, the animal-human interface is extremely important and needs to be studied…

Asked by Sky News whether there was a good reason not to include the WHO, Dr Galea replied: “From our point of view, no.”

I guess the question is why, from China’s point of view, they don’t want anyone looking over their shoulder as they investigate this. China has reacted strongly to suggestions that the virus might have escaped from a laboratory. U.S. intelligence agencies say they are still investigating that possibility but have ruled out that the virus itself was man-made.

Yesterday, President Trump was asked if he’d seen any evidence that the virus might have escaped from the Wuhan Institute of Virology and he said that he had but when pressed he replied, “I can’t tell you that. I’m not allowed to tell you that.”

One thing that might help rule out the accidental lab release theory is an examination of records from the lab, but Dr. Galea says China hasn’t allowed access to that information:

Dr Galea also told Sky News that the WHO had not been able to investigate logs from the two laboratories working with viruses in Wuhan, the Wuhan Institute of Virology and the Wuhan CDC.

“From all available evidence, WHO colleagues in our three-level system are convinced that the origins are in Wuhan and that it is a naturally occurring, not a manufactured, virus,” he said.

Nevertheless, according to Dr Galea, the laboratory logs “would need to be part of any full report, any full look at the story of the origins”.

While the Wuhan market origin of the virus is still considered likely, China has also not released any data that would back up that origin. For instance, China has claimed that after it shuttered the market it tested animals found there and found samples of the coronavirus, but the details, such as which animals were tested and the test results, have not been released.

The other problem with the wet market theory is that about a third of the initial cohort of 41 cases did not have a connection to the market. In fact, the person believed to be the first person to come down with the disease hadn’t been to the market. That’s not to say the disease didn’t spread at the market, it clearly did early on, but the evidence that the market was the origin point is still lacking.

Here’s the interview with Dr. Galea. Toward the end of this he talks about how after China hesitated on saying the virus was transmitting person-to-person, WHO doctors went to China where doctors treating infected patients immediately volunteered that virus had spread to health care workers. The day of that visit was the day China’s government finally acknowledged human-to-human transmission.

Finally, yesterday the Washington Post published a 10-minute video exploring the question of the origin of the virus. It’s not perfect as it leaves out a couple of things but it does a pretty good job of pointing out why the wet market origin is still partly in doubt and why the accidental lab release theory hasn’t been ruled out. Until China becomes more open to having outside doctors look at their work or U.S. intelligence agencies release all they know, we’re left trying to judge between two incomplete and unsatisfactory stories of the origin.