In an interview set to be aired in full this Sunday, Robert Redfield, former director of the Centers for Disease Control and Prevention under President Trump, has become the latest and most mainstream voice so far to offer support for a controversial but not implausible theory about the origins of the covid-19 pandemic: that the coronavirus behind it all ultimately came from a research lab in China, where the first cases of the now global viral illness were reported in December 2019.
The interview is part of a CNN special this Sunday night on the pandemic, featuring discussions with some of the public health experts and doctors most prominently involved in the Trump administration’s response to the covid-19 pandemic. And while much of the special will go over the numerous failures in the U.S. to effectively contain the pandemic, the much-criticized Redfield also took some time to comment on where he thinks the coronavirus—officially called SARS-CoV-2—first originated.
“I do not believe this somehow came from a bat to a human,” Redfield told CNN correspondent Sanjay Gupta in a clip posted to YouTube on Friday. “Normally, when a pathogen goes from a zoonot to human, it takes a while for it to figure out how to become more and more efficient in human-to-human transmission.”
By “zoonot,” he’s referring to an animal source of a disease. “Zoonotic” is the more common term that describes infectious diseases that are transmitted from animals to humans.
Redfield was careful to couch his statement as simply an opinion but cited his long career as a virologist in justifying his belief. He went on to say that though he believed a lab escape was the most likely explanation for the pandemic, that doesn’t necessarily mean the coronavirus was intentionally released by any nefarious parties. In other words, a mistake, not a bioweapon.
From nearly the very beginning of the pandemic, a sizable contingent of people have argued that SARS-CoV-2 was manmade. Some of these arguments are completely ludicrous and plainly inaccurate, such as the idea that the coronavirus had to be created using some of the same genes as the HIV virus. But Redfield’s theorized version of events is at least plausible.
Researchers do sometimes manipulate viruses naturally found in animals in ways that could possibly make them better at infecting humans. And there was coronavirus research going on in Wuhan around the time the first reported cases of covid-19 emerged there. But plausible isn’t the same as likely, of course.
Other research has suggested that there’s nothing inherent about the genetics of SARS-CoV-2 that would preclude it from being naturally created. Bats may have been the original host of its recent ancestor, but it’s possible that the virus evolved in an intermediate host such as pangolins before it reached humans and that this allowed the virus to become better adapted to us. It’s also possible that the virus was circulating silently in humans for some time and evolved from there to become the more transmissible menace that kickstarted the pandemic. Even during the pandemic, the virus has mutated several times to become better at infecting us.
It’s quite possible that a leak from a lab set things in motion this time—indeed, U.S. diplomats reportedly sounded the alarm in 2018 about unsafe practices at the Wuhan Institute of Virology—though nature typically doesn’t need our help to launch a new pandemic. We know that pandemics can emerge from zoonotic transmission because it happens all the time, including with the last flu pandemic we had in 2009. Zoonotic diseases are probably the most likely diseases to become a pandemic, since they can meet many of the necessary criteria up front, such as low preexisting immunity among humans. The chances of any one zoonotic outbreak or germ becoming a pandemic may be low, but even low-probability events become a certainty when you provide enough opportunities for them to happen.
Last month, the World Health Organization issued preliminary findings from its investigation on the origins of the pandemic. They concluded that it was “extremely unlikely” for a lab leak in Wuhan to have caused the first cases of the pandemic and that zoonotic transmission was the most likely explanation. Though WHO officials claimed that China was largely cooperative during the investigation, investigators were barred from viewing some sources of information, namely the raw data collected on the first cases in Wuhan. Early on in the pandemic, Chinese government officials also tried to stifle information about the local outbreaks ongoing in the country.
Other scientists and investigative journalists have also started to call for a more serious discussion of the lab leak hypothesis. With Redfield’s interview airing Sunday, it’s likely this theory is about to get a whole lot more attention, but who knows whether concrete evidence will be found to support it.