Since the beginning of the pandemic, there has been debate about where the new virus called Sars-CoV-2 came from. The virologist Christian Drosten from the Charité in Berlin considers it very likely that this is a natural phenomenon and that traces of its origin in wild animals or breeding farms could still be found, said Drosten in an interview with the Süddeutsche Zeitung. He did not want to rule out the possibility that the disease originated in a laboratory, “but it is currently only a possibility”.
The debate about the origin of the new corona virus was fueled last week by two interviews given by the Hamburg physicist Roland Wiesendanger to the magazine Cicero and the Swiss daily newspaper NZZ. In it, the researcher spreads his speculation that Sars-CoV-2 came from a laboratory in the Chinese city of Wuhan. He accused leading international virologists like Drosten, who assume the virus originated in the animal kingdom, to be deliberately misleading and covering up.
Wiesendanger refers to a switching conference of international experts that took place in early February 2020, which the US presidential adviser Anthony Fauci had suggested. He wanted to discuss the hypothesis of a non-natural origin of Sars-CoV-2 in detail with a group of international experts. According to Wiesendanger, as part of this panel of experts, Drosten is said to have helped to disguise the supposed laboratory origin. There is no evidence for this claim.
Does the furin cleavage site show that the virus has been deliberately manipulated?
In an interview with the SZ, Drosten resolutely countered Wiesendanger’s allegations. “You can see in all of my public statements that I’ve always been open to both possibilities. I just always said that’s why I think a natural origin of the virus from the animal kingdom is more likely for verifiable reasons.” In the switching conference in question with international experts in February 2020, no pressure was exerted and no possibility was ruled out. “In the end, we came to the conclusion that we could say neither ‘yes’ nor ‘no’ to the laboratory hypothesis.”
From the point of view of the proponents of the laboratory hypothesis, one molecular feature of Sars-CoV-2 speaks in particular for a man-made origin in the laboratory. The so-called furin cleavage site, which enables the pathogen to infect cells in the respiratory tract, is not actually found in this form in the group of corona viruses that also includes Sars-CoV-2 – but certainly in other corona viruses. According to Wiesendanger, this suggests that the cleavage site was installed.
Drosten does not consider this conclusion to be justified. “The diversity of these viruses has not yet been well researched, which is why the furin cleavage site is conspicuous, but no evidence of a non-natural origin,” says Christian Drosten. Last year, samples from bats were examined in his laboratory. In doing so, his team came across two specimens of Sars-related viruses in which only one mutation would be necessary, “and then these viruses would also have a furin cleavage site similar to that of Sars-CoV-2,” says Drosten. “If only such small changes in the genome are necessary, you can definitely expect something like this to happen in nature.”
Drosten also does not see the fact that experiments were carried out in a high-security laboratory in Wuhan to give viruses new properties as evidence of an unnatural origin of Sars-CoV-2. “Things were done in Wuhan that could be described as dangerous. But the Sars-CoV-2 virus could not have come out of it.” In the laboratory in Wuhan, bat viruses had new properties built into them, but not those that could be considered the predecessors of Sars-CoV-2.
Drosten misses studies on civet cats or raccoon dogs
Drosten would have wished for more transparency from those responsible on site, but also from the US research institutions cooperating with the institute in Wuhan. “Right from the start, when these public allegations came, you should have communicated aggressively and proactively what was being done there in the laboratory,” says the Charité virologist.
Drosten is convinced that two years after the start of the pandemic, something can still be found out about the origin of the pandemic. Like many other experts, he also suspects that Sars-CoV-2 originally originated in bats and finally jumped to humans via an intermediate host. Drosten misses usable studies on corona viruses in animals in China that could be considered intermediate hosts, such as civets or raccoon dogs. “They are known to be bred and sold in many parts of China, primarily by the fur industry. I would actually have expected that everything would be taken apart with full enthusiasm to find the origin. But there is surprisingly little data on this, which I find striking”. In any case, the origin will not be found out from the USA or Germany. “It needs the will of China.”