“We do expect those [research areas] to be pursued, we are working with our Chinese counterparts through technical collaborations and there’s a lot of behind-the-scenes discussions that are happening as well.”

China’s Covid origins snub shows limits to WHO’s power

The American epidemiologist said further research in China was “of the highest priority”, and this could include international support. “We always envisioned that there would be multiple missions to China, so we expect that there would be more. Again we need to do this with China, we need their cooperation to be able to have those missions,“ she said.

Sago could hold its first meeting as early as next month and marks the first concrete step towards a second-phase study into Covid-19 following an initial research mission centred on Wuhan, the central Chinese city where the disease was first detected.

The United States and a handful of allies said the findings of the mission, a joint effort between international and Chinese scientists, were compromised by a lack of transparency from China – a charge Beijing rejects.

02:23

Covid-19 returns to China’s Wuhan as Delta variant spreads to 10 provinces

Covid-19 returns to China’s Wuhan as Delta variant spreads to 10 provinces

Other critics said the initial WHO team was too quick to conclude a lab leak was “extremely unlikely”. Beijing has denied this happened and accused the US of pushing for the investigation to slander China.

Van Kerkhove said: “There’s a lot of different avenues that need to be pursued … but the studies in China are not finished, and they need to be completed.”

Recommendations for investigation will soon be in the hands of Sago, which is seeking specialists in many fields, including virologists, veterinary surgeons, ecologists and biosafety experts. Selection criteria will take into account geographic representation, gender balance and conflicts of interest.

The plan is to make it a permanent body to advise the WHO on the origins of emerging and re-emerging diseases.

The first task of the group on Covid-19 is to evaluate research – including studies published in the five months since the initial WHO team released its report – and set priorities for what needs to be done next, according to Van Kerkhove.

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Its recommendations may prompt field missions to China and other places where there is evidence of potential early Covid-19 cases or animals with related viruses. Those could involve specialists from outside Sago and would need coordination with the host countries, she said.

Critics of the new plan have said that the process of forming a new group could slow down time-sensitive work, especially because it is almost two years since the virus is thought to have started spreading among people.

This concern was raised in a commentary published in the journal Nature on Wednesday, where the independent scientists who took part in the phase one mission to China said the new process “runs the risk of adding several months of delay”.

On Wednesday, WHO chief Tedros Adhanom Ghebreyesus insisted Sago “will not delay the progress of the studies into the origins of Sars-CoV-2” because the initial report highlighted research that could be done “without delay” domestically.

07:07

The global spread of the highly contagious Delta variant of Covid-19

The global spread of the highly contagious Delta variant of Covid-19

Many of those studies, such as those on wildlife farms or testing stored biological samples to look for earlier infections, are expected to take place in China.

Last month Liang Wannian, the leader of the Chinese team that took part in the earlier WHO mission, said China was “actively carrying out” studies recommended in the report and would share the results with the WHO.

But the WHO was largely in the dark about what those studies entailed, said Van Kerkhove, who added: “Ideally we would know what is ongoing but we don’t.”

Dutch virologist Marion Koopmans, a member of the phase one team, which remains in touch with their Chinese counterparts, said earlier this week she was “not aware of studies ongoing”.

The inclusion of the Wuhan laboratory audit in the proposals risked further delays to collaborative work in China, said Koopmans.

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But lab biosecurity and biosafety is important because Sago will need such protocols both for Covid-19 and future disease outbreaks.

“I think we need to recognise that any future emergence will likely have the suspicion of a breach in biosafety, biosecurity or some kind of manipulation of a virus, and so we need to put on the table that this is something that can be evaluated,” Van Kerkhove said.

While Sago gave the WHO a more independent mechanism to assess disease outbreaks, it was unlikely to dial down the political wrangling around the lab-leak theory, said David Fidler, a senior fellow for global health at the Council on Foreign Relations in New York.

“I’m sorry, but depoliticisation will not be possible when the world’s two most powerful countries are deliberately doubling down on making the origin issue important in their geopolitical and ideological rivalry,” Fidler said.

He pointed to recent calls from Chinese diplomats for the WHO to investigate an American military lab, while US lawmakers are requesting congressional investigations of China’s role in the outbreak.

Van Kerkhove said the WHO was “not naive” about the political challenges, but it would focus on a standardised, scientific approach.

US will not accept WHO findings out of Wuhan without verifying

“We don’t want it to be ad hoc, we want to tick everything off those boxes and really just make sure we pursued every avenue,” she said.

“As answers are provided, as data is shared, and as results are made available, we will be able to narrow down. We cannot do that without the data, and we cannot do it without the studies being conducted and without the results being shared, everywhere.”