United States President Joe Biden called on Wednesday, May 26, the American intelligence services to "redouble their efforts" to explain the origin of Covid-19, once again deploring the lack of cooperation and transparency from Beijing.

Long brushed aside by most experts, the theory of a laboratory accident in Wuhan, China, has come back in force in recent weeks in the American debate.

And calls for more in-depth investigation are growing within the scientific community.

The work of the American government, which focuses on two hypotheses - animal original or leakage from a laboratory - has so far failed.

90 day ultimatum

"I asked the intelligence services to redouble their efforts to gather and analyze the elements that could bring us closer to a final conclusion", underlined the tenant of the White House, specifying that he awaited conclusions from here 90 days.

He also wants a list of "specific questions" that should be put to China.

Concretely, how does he intend to move the lines on this file frozen for months?

Will he address the issue directly with his Chinese counterpart Xi Jinping?

What leverage is he ready to use?

Assailed with questions during the daily White House press briefing, Karine Jean-Pierre, spokesperson for the US executive, remained evasive, sticking to the reminder of the 90-day deadline.

"China must do more," she insisted.

"Conspiracy theories"

Beijing has always fiercely fought the theory that the Covid-19 could have escaped from one of its laboratories.

The Chinese Embassy in the United States said on Thursday that the politicization of the origins of Covid-19 would hamper investigations.

China is backing "a full study of all the first cases of Covid-19 discovered around the world and a full investigation of certain secret bases and biological laboratories around the world," the embassy said in remarks attributed to a spokesperson. parole, published on its website.

In his text, the American president believes that the impossibility for the American health authorities to go on the ground in China in early 2020 "will always hamper any investigation into the origin of Covid-19".

But despite everything, he calls for a change in the posture of the second world power.

"The United States will continue to work with its partners around the world to pressure China to participate in a full, transparent, and evidence-based international investigation."

Unpublished information

On Sunday, the Wall Street Journal claimed to have had access to unpublished information from American intelligence, reporting that three researchers from the Wuhan Institute of Virology had been affected by November 2019 with "symptoms compatible with both those of Covid-19 and seasonal infection ", requiring hospital treatment.

Beijing has denied this information, calling it "totally false". 

After a four-week stay in Wuhan at the start of the year, a joint study by experts from the World Health Organization (WHO) and Chinese had judged in March "extremely unlikely" a laboratory accident.

But the boss of the WHO himself, Tedros Adhanom Ghebreyesus, had called for a new investigation into the hypothesis of the laboratory leak.

In mid-May, around fifteen experts published a column in the prestigious journal Science.

"We need more research to determine the origin of the pandemic," they claimed.

Theories of animal or accidental laboratory origin "both remain viable", they wrote, but "they have not been given fair consideration."

With AFP and Reuters

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