The former head of the main federal public health agency in the United States believes the coronavirus came out of a laboratory in Wuhan, the cradle of the pandemic, he said in an interview broadcast on Friday.
"If I had to speculate, this virus started to spread around September-October in Wuhan, China,"
Robert Redfield, who headed the Centers for Disease Prevention and Control (CDC) under Donald Trump.
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"I still think that the most likely etiology of this pathogen in Wuhan is a laboratory from which it escaped,"
he added, stressing that it was
"only an opinion"
.
Etiology is the study of the causes of diseases.
It
"is not unusual"
that respiratory pathogens studied in a laboratory contaminate employees, explained the former director of CDC, whose specialty is virology.
This hypothesis was notably promoted by the former government of Donald Trump, but experts sent to China by the World Health Organization (WHO) in January-February had seemed to exclude it.
The boss of the WHO, Tedros Adhanom Ghebreyesus, however, estimated that
"all the assumptions remain on the table".
Wuhan is home to the Institute of Virology, at the heart of the controversy over the origin of the pandemic because it studies many viruses, including the bat coronavirus.
The generally accepted theory is the natural transmission of this virus from bats to humans, probably via another animal.
The first cases reported in Wuhan in December 2019 and January 2020 are linked to an animal market, suspected of being the source of the contamination or of having amplified it.
This thesis
"does not make sense in biology",
ruled Robert Redfield, while specifying not to imply that an intentional act was at the origin of the release of the virus.
When moving from animal to human, the virus
"takes a long time to become more and more efficient in human-to-human transmission
," he said.
Robert Redfield also hinted that the Wuhan Institute could have
"improved"
the virus to make it more effective.
“Let's say I have a coronavirus that I'm working on.
Most of us in the lab are trying to grow it and improve it to experiment and find solutions, ”
he said.
Robert Redfield's theory has been challenged by Anthony Fauci, renowned immunologist and Joe Biden's main health adviser.
Improving the virus in the lab
"is a possibility,"
he said,
"but the most likely, and one that most health officials agree on, is that (the virus) has passed. without being detected, spreading through the population for several weeks or months, which allowed them to adapt well before being clinically identified ”.
