Despite a high-profile visit to China by a team of international experts in January, the world is no closer to knowing the origins of Covid-19, according to one of the authors of an open letter calling for a new investigation.
Vaccines expert Nikolai Petrovsky of Flinders University, one of 26 global experts who signed the open letter, published Friday, said “at this point we are no further advanced” than a year ago.
"Based on our analysis, and as confirmed by the global study convened by the World Health Organisation (WHO) and Chinese authorities, there is as yet no evidence demonstrating a fully natural origin of this virus," the letter says.
"The zoonosis hypothesis, largely based on patterns of previous zoonosis events, is only one of a number of possible SARS-CoV-2 origins, alongside the research-related accident hypothesis."
In January, a team of scientists picked by the WHO visited hospitals and research institutes in Wuhan, the central Chinese city where the coronavirus was identified, in search of clues about the origins of Covid-19.
But the mission has come under fire, with critics accusing the WHO of relying too much on politically compromised Chinese fieldwork and data.
Team members also said China was reluctant to share vital data that could show Covid-19 was circulating months earlier than first recognised.
The open letter said the WHO mission "did not have the mandate, the independence, or the necessary access to carry out a full and unrestricted investigation" into all theories about the origins of Covid-19.
"With more than two million deaths, more than a hundred million infected worldwide, and a massive global disruption impacting some of the world’s most vulnerable populations, we cannot afford an investigation into the origins of the pandemic that is anything less than absolutely thorough and credible."
At this point, Professor Petrovsky believes nothing can be ruled out.
"All possibilities remain on the table and I have yet to see a single piece of independent scientific data that rules out any of them," he said.
At a press briefing to mark the end of the WHO visit to Wuhan, mission head Peter Ben Embarek appeared to rule out the possibility that the virus leaked from a laboratory in Wuhan.
But Professor Petrovsky said it "doesn't make any sense" to rule any possibility out, and said the aim of the open letter was "to get an acknowledgement globally that no one has yet identified the source of the virus and we need to keep searching".
"We need an open mind and if we close down some avenues because they are considered too sensitive, that is not how science operates," he said.
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