ARI SHAPIRO, HOST:
The World Health Organization says it has wrapped up an investigation into COVID-19 in China. The goal was to learn about the origins of the pandemic. And here to tell us what they found is NPR's global health correspondent Michaeleen Doucleff.
Hi there.
MICHAELEEN DOUCLEFF, BYLINE: Hi.
SHAPIRO: What exactly has the WHO team been doing in China?
DOUCLEFF: So, Ari, the team includes more than a dozen researchers, and they've been in Wuhan visiting all the places critical in the early days of the pandemic. So they went to the Huanan Seafood Market. They also talked to first-known COVID patients and the doctors that treated them. And they met with coronavirus researchers.
SHAPIRO: And what did they learn?
DOUCLEFF: Well, the WHO hasn't issued a report of their scientific findings. Basically, the team only discussed some main conclusions at a press conference today. One of those was about whether or not the virus leaked from a laboratory, specifically the Wuhan Institute of Virology.
SHAPIRO: We heard a lot about that lab early in the pandemic, where scientists studied coronaviruses. Tell us more about what they learned.
DOUCLEFF: Yeah. So scientists pretty much agree that the virus that causes COVID-19, SARS-CoV-2, came from bats. And at this lab, researchers had extracted several other coronavirus from bats inside China. And so there's been a theory that perhaps the virus infected a researcher and then spread COVID-19 to the community. At the press conference, WHO said this hypothesis is very unlikely.
SHAPIRO: OK, so they knocked down the idea that this came from a lab. Did they say what evidence there is to rule that out?
DOUCLEFF: Well, right now, Ari, it appears that the evidence comes primarily from a visit to the Wuhan Institute of Virology itself. The WHO team said they had a long, frank discussion with researchers there, and the institute provided, quote, "detailed description" of all their work on coronaviruses. Dr. Liang Wannian led the Chinese part of the investigation. He said through an interpreter, there is no evidence that any labs studied SARS-CoV-2.
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LIANG WANNIAN: (Through interpreter) In all the laboratories in Wuhan, there is no existing virus of SARS-CoV-2. If there is no existence of this virus, there will be no way that this virus would be linked.
SHAPIRO: OK, so it's clear the virus did not come from a lab. Did they get any evidence of where it did come from?
DOUCLEFF: So the team says the most likely hypothesis is that the virus started in a bat, jumped into an intermediate host, like a pangolin or mink, and then into humans. And exactly what animal that is and where that happened is still a big mystery. However, they said the pandemic did not start in the Huanan Seafood Market. The virus was already circulating before then. And so they're trying to figure out how the virus got to the market. And one possibility, Ari, they said, could be frozen foods.
SHAPIRO: Explain to us how that would work - the virus coming through frozen foods.
DOUCLEFF: Yes, so this is a hypothesis that many scientists have dismissed repeatedly, but some Chinese scientists believe the virus has been imported into China several times through frozen meats - not like the pizzas that come to the grocery store but meat of infected wild animals. Dr. Peter Embarek, who led the WHO team, says this needs to be studied more.
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PETER EMBAREK: We know that the virus can persist and survive in conditions that are found in these cold and frozen environments, but we don't really understand if the virus can then transmit to humans.
DOUCLEFF: So, Ari, right now, this investigation has raised more questions than it has answered.
SHAPIRO: NPR's Michaeleen Doucleff, thank you.
DOUCLEFF: Thank you, Ari.
(SOUNDBITE OF MUSIC) Transcript provided by NPR, Copyright NPR.