China hasn’t provided evidence to disprove that theory, while the search for signs that the virus emerged from wildlife hasn’t yielded results, Gottlieb said on CBS News’s “Face the Nation.”

Biden Renews Virus Origin Probe That’s So Far Come Up Empty

Not knowing how the pandemic started puts the world at risk of future outbreaks, Peter Hotez, co-director of the Texas Children’s Hospital Center for Vaccine Development, said in a separate TV appearance.

“There’s going to be Covid-26 and Covid-32 unless we fully understand the origins of Covid-19,” Hotez said on NBC’s “Meet the press.”

Almost a year and half after the new pathogen was first detected spreading in a seafood market in Wuhan, China, the precise origins of the virus remain obscure. Scientists have hypothesized that it most likely spread from wild animals to humans. The idea that the virus may have accidentally escaped from a research lab, long promoted by some Republicans, has gotten renewed attention from the Biden administration.

In a surprise statement on Wednesday, President Joe Biden called for a renewed investigation into the virus’s emergence. U.S. intelligence agencies had conflicting assessments of whether it was more likely the virus crossed the species barrier from a natural reservoir or leaked from the Wuhan Institute of Virology, Biden said. He ordered the agencies to “redouble their efforts” and report to him again in 90 days.

China Accuses U.S. of Hyping Theory Virus Escaped From Lab

Debate over the virus’s origin was fueled anew by a Wall Street Journal report on May 23 that three researchers from China’s Wuhan Institute of Virology became sick enough in November 2019 that they sought hospital care for “symptoms consistent with both Covid-19 and common seasonal illness.”

Scientists should be allowed to conduct a long-term investigation in China and take blood samples from humans and animals, Hotez said. The U.S. should pressure China, including with the threat of sanctions, to allow for an inquiry.

“We need a team of scientists, epidemiologists, virologists, bat ecologists in Hubei province for a six-month, year-long period,” Hotez said.

Chinese officials have disputed the Wuhan lab theory. Foreign Ministry spokesman Zhao Lijian on Thursday dismissed Biden’s inquiry as an attempt to engage in “stigmatization, political manipulation and blame-shifting.”

A World Health Organization report released in March didn’t fully uncover the virus’s origin but called a lab leak unlikely. The global health body called for more investigation at that time.

“As far as WHO is concerned, all hypotheses remain on the table,” Director-General Tedros Adhanom Ghebreyesus said in a statement when the March report was released.