Professor Jesse Bloom found dozens of test samples from the earliest confirmed Covid patients in epicentre Wuhan had been pulled by Chinese scientists from an international database
Chinese scientists have deleted crucial data from the earliest confirmed Covid patients, it emerged today amid intense scrutiny about the true origins of the disease.
Dozens of test samples from patients in epicentre Wuhan were found to have been wiped from an international database used to track the virus' evolution.
The files could have provided vital clues about how the virus originated and how long it had been spreading before the seafood market outbreak in December 2019.
The American professor who spotted their deletion and managed to recover some of the data said they suggested Covid was circulating long before China's official timeline.
He found the early samples of the virus were much more evolved than would be expected of a pathogen that had recently jumped from animals to humans.
Professor Jesse Bloom, a virologist from the Fred Hutchinson Cancer Research Center in Seattle, said he believed China had removed the files to 'obscure their existence'.
British scientists told MailOnline the findings confirm Covid was spreading in people before being linked to wet markets, 'perhaps months before'.
The latest cover-up comes amid mounting suspicion that the virus may have accidentally leaked from a high-level biosecurity laboratory in Wuhan.
In a tweet this morning, Boris Johnson's former chief aide Dominic Cummings said Professor Bloom's find pointed further 'towards' the 'lab leak' theory.
The files (shown to have been removed, above) could have provided vital clues about how the virus originated and how long it had been spreading before the outbreak was reported in December 2019
While China has tried to insist the virus originated elsewhere, academics, politicians and the media have begun to contemplate the possibility it leaked from a high-level biochemical lab in Wuhan - raising suspicions that Chinese officials simply hid evidence of the early spread
The cover-up was detailed in a scientific paper titled 'Recovery of deleted deep sequencing data sheds more light on the early Wuhan SARS-CoV-2 epidemic' today.
Forty-five positive samples had originally been uploaded to the National Institute of Health‘s Sequence Read Archive by the Wuhan University in early March 2020.
They were published as part of a study into diagnosing Covid patients using PCR tests just days before the Chinese Government issued an order requiring approval of all Covid data.
Professor Bloom noted that all 45 samples have since been pulled from the database, with 'no plausible scientific reason for the deletion'.
He said the most likely explanation was to 'abuse' and 'obscure' the truth about the origins of the pandemic.
The virologist was able to partially recover 13 of the sample using Google Cloud and sequence the viruses.
He noted several genetic differences between the strains in the deleted samples and the virus that eventually spread around the world.
In a Twitter thread detailing his findings today, Professor Bloom said: 'Although events that led to emergence of #SARSCoV2 in Wuhan are unclear (zoonosis vs lab accident), everyone agrees deep ancestors are coronaviruses from bats.
In a tweet this morning, Boris Johnson's former chief aide Dominic Cummings said Professor Bloom's find pointed further 'towards' the 'lab leak' theory
The latest cover-up comes amid mounting suspicion that the virus may have accidentally leaked from the Wuhan Institute of Virology (pictured)
'Therefore, we’d expect the first #SARSCoV2 sequences would be more similar to bat coronaviruses, and as #SARSCoV2 continued to evolve it would become more divergent from these ancestors. But that is *not* the case!
'Instead, early Huanan Seafood Market #SARSCoV2 viruses are more different from bat coronaviruses than #SARSCoV2 viruses collected later in China and even other countries.'
British experts commenting on the study said it confirmed long-held suspicions that Covid was spreading before December 2019.