-This is the Wuhan seafood market.
On January 1st, it was shut down.
Many of the early cluster of confirmed cases
had been in the market, so officials feared
that COVID-19 was linked to trade and wild animals.
It sold everything, from snakes to birds to foxes and rabbits.
But the viruses most similar to the new coronavirus
that causes COVID-19 are from bats
that live in caves a thousand miles away,
but just because they're similar doesn't mean they're the same.
-I just am baffled about this story.
-As of late April, experts don't have
all the information we need to say where the virus started.
-If the Chinese know evidence,
of course they're not telling us or anybody else.
-With the absence of crucial evidence comes many theories.
One is that it came from nature,
which scientists say seems most likely.
Another theory is that it was a bioweapon,
which scientists say there's zero evidence for.
-I guess without putting too fine of a point on it,
it would fall in the realm of conspiracy theory.
-We're going to focus on one theory
that both US intelligence and lawmakers are examining,
that the virus accidentally escaped from a lab.
At least two labs in Wuhan research bat coronaviruses,
the Wuhan Institute of Virology and the Wuhan branch
of the Chinese Centers for Disease Control & Prevention.
They have become the focal point of suspicion,
not only because of the work that they do
but because of their location.
Both are close to the market.
The Wuhan Institute of Virology is about eight miles away,
and the Wuhan branch of the Chinese Centers
for Disease Control & Prevention is just 300 yards.
Safety concerns at both labs have come up in recent years.
For instance, in this video, we see one of the scientists
from the Wuhan Centers for Disease Controls &
Prevention doing research on coronaviruses in bats
while not wearing protective gear,
but regardless, if researchers are in the field
or in the lab, most bat coronaviruses
scientists have identified aren't dangerous to humans.
-They're not considered major potential pathogens
because they just don't grow very well
in other species besides bats.
-That's why most labs who study bat coronaviruses
do not require the highest level of safety protocols.
The safety situation at the other lab is a bit different.
The Wuhan Institute of Virology houses multiple labs,
including one that has the highest level
of biological safety protocols, biosafety level four.
It is designed to contain
some of the world's most dangerous viruses.
-BL-4 is the ones you will see in films with people in a suit
and an air hose attached behind them,
and they're completely enclosed and protected.
-When China first brought the lab online,
it was with the explicit goal of studying coronaviruses.
-China wanted to set up its own laboratory
after the SARS outbreak to study SARS-relevant pathogens
so that they could do that on their own territory
without having to rely on the international system.
-Shi Zhengli -- she's one of the world's experts
on bat coronaviruses
and is based at the Wuhan Institute of Virology.
-The work we do with the Wuhan Institute of Virology
is to look for viruses in bats
that we think could be the next pandemic.
-That work and the higher safety protocols have led to suspicion
that Shi was working with more dangerous bat coronaviruses,
ones that could infect humans.
-Recent reports have come out
that there were concerns being raised
by US scientists and diplomats about the level of safety,
training, and general protocols there and concern
that this was the kind of thing that could lead to leakage.
-Two years ago, American officials voiced
a variety of concerns about these labs,
including the ominous warning
that there was a serious shortage
of appropriately trained technicians and investigators.
-Without fail, every single BSL-4 lab in the US
gets some type of safety violation,
some type of, you know, thing that they could do better,
and that's the purpose of doing those inspections,
is to make sure that biosafety is as tight
and secure as it can possibly be.
-But even in the most safe labs, things go wrong.
That same 2018 State Department cable that described
the possible safety issues
also warned about the dangerous nature of Shi's research.
They wrote, "Researches also showed various SARS-like
coronaviruses can interact with ACE2,
the human receptor identified for SARS-coronavirus.
This find strongly suggests
that SARS-like coronaviruses from bats
can be transmitted to humans to cause SARS-like diseases."
Shi's team reported this in a 2017 paper,
but that paper doesn't show these coronavirus samples
were effective at infecting humans.
And the virus used in that research
was not the virus that causes COVID-19.
It's the underlaying experiment that has raised flags.
Researchers at one point had a live virus
that could infect a human cell.
Just weeks into the outbreak, researchers from Shi's lab
found the virus had a 96% similarity
with a bat coronavirus they had previously researched.
-So they both come from, you know,
this same distant relative,
same, like, great-great-great virus-grandfather.
-And though these two viruses have diverged, that 4% change,
it's the part that makes all of the difference to us.
-The part of the virus that binds to the receptor
on human cells for the SARS-Co-V-2,
it's very different than the bat coronavirus,
the part that allows the animal virus to infect humans.
Otherwise, it's interesting,
but it's not gonna cause any outbreaks in people.
-That means this virus and other currently known
bat coronaviruses could've picked up the features
from just the right intermediary animal,
allowing it to be able to jump to humans.
-And really, what we won't be able to find out
unless we can identify
whether there is an intermediate species.
We have to actually see the ancestor of SARS-Co-V-2
to know exactly what type of adaptations it underwent
in order to be able to infect humans,
the smoking pangolin or the smoking whatever else.
-Of course, the potential of great-great-great
virus-grandfather isn't the only bat coronavirus in Shi's lab.
Even Shi was initially concerned that her lab
could've caused the outbreak.
But since then, she says she's ruled out the possibility.
Shi, her team, and the Chinese government have adamantly denied
that it could've come from this lab.
-There's no way this virus came from us.
-China's been incredibly open,
and I believe it's because it's a scientific collaboration.
And in China, they're really proud of their science.
They do good work, especially in virology.
-The evidence that a lab accident
led to the release of the virus that causes
COVID-19 is circumstantial, but speculation has heightened
because of the actions of Chinese officials.
First, before the Chinese government had even alerted
the World Health Organization to the growing epidemic,
scientists were told to destroy early samples of the virus,
according to the Times.
After the Chinese government reported the virus to the WHO,
officials quickly pointed to the seafood market
as the source of the virus and shut it down.
-The Chinese government acknowledged it began in Wuhan
and put out this story of the wet market.
It was a kind of unusual,
specific pinning on the part of the Chinese government,
like not their general way of operating.
-But many of the first-known COVID-19 cases
were not traceable to the Huanan Seafood Market.
-The initial patient did not have any link to the market.
-The Chinese government reported
that they had found samples of the coronavirus
in the western end of the market that is known to house wildlife,
but to confirm that, scientists would need specimens
from the animals in the market.
-As of today, as to my knowledge,
and I look for this every single day for 112 days,
China has not divulged any information
about what animals they tested from the market
when the closed it,
and, of course, what the results of any of those tests were.
-The only way to find an answer to this mystery is with a sample
that matches both the virus and matches the first patients,
which scientists haven't been able to find.
Even if there was a perfect match to the virus
in one of these labs,
without early patient samples, there's no way to be sure.
The balance of scientific evidence strongly suggests
the conclusion that the new coronavirus emerged from nature,
be it in the Wuhan market or somewhere else.
Too many perfect coincidences would've had to take place
for it to have escaped from a lab,
but the Chinese government has not been willing
or able to provide information
that would clarify lingering questions
about any possible role played by the Wuhan labs.
-Seems like such a remarkable coincidence
that you have an outbreak of a coronavirus in theory
from a bat in the same city
where there is this high level BSL-4 laboratory
where not only are there foreign concerns about its safety,
but there are, like, Chinese articles
about the safety protocols not being sufficient.
And obviously, there's no smoking gun.
It's all circumstantial, but it's pretty remarkable.
And it's the kind of thing where it raises questions.
-That is why intelligence agencies
are still exploring the possibility,
no matter how remote it may be, and even then, it's unclear when
or if we will ever know the origin story
of this new virus that is causing so much death
and economic turmoil around the globe.