British scientists were conducting experiments that risked creating more dangerous variants during the pandemic, it has been claimed.
In tests led by Imperial College London and funded by the UK Health Security Agency (UKHSA), cells were simultaneously infected with Delta and Omicron to see what had a competitive edge.
Anton van der Merwe, a professor of molecular immunology at Oxford University, said such experiments risked combining the two variants to produce something “more deadly” that could have infected scientists or leaked from the lab.
“Coronaviruses like Sars-CoV-2 are known to ‘evolve’ by swapping genetic material when two different viruses infect the same cell,” he said.
“This makes it much more likely that these strains will ‘recombine’ and create a more dangerous variant that could infect those conducting the experiments, who could then spread it throughout the community.”
Experiments “according to strict regulations”
Prof van der Merwe said using Delta and Omicron was particularly risky because they came from different lineages and had more differences than the variants closer to the original Wuhan strain.
Imperial College London defended the experiments, which took place in London, arguing they were needed for the pandemic response. She added that they were conducted under high biosafety standards.
A spokesman for the university said: “This government-backed research used viruses no more pathogenic than those already circulating in the population and will provide crucial insights that support government decision-making to manage the pandemic.
“It was performed in a biosafety level 3 laboratory under strict regulatory requirements and received ongoing approval from the Health and Safety Executive.”
Since the pandemic began, there have been fears that Covid-19 has leaked from a lab in Wuhan where researchers have been conducting experiments on bat coronaviruses.
In recent decades, smallpox, swine flu, Sars and anthrax, and foot-and-mouth disease have escaped through leaky laboratories.
This week, a report from King’s College London warned that labs carrying dangerous pathogens are on the rise. Three quarters of high-security facilities are now in urban areas, increasing the risk of a leak.
The report’s authors said many countries are conducting “risky research” that could lead to the “accidental or deliberate release of a pandemic-prone pathogen.”
dr Filippa Lentzos, Co-Director of the Center for Science and Safety Studies at King’s College London, said: “The construction of laboratories that handle dangerous pathogens has boomed around the world, but this has not been matched by adequate biosafety and biosafety oversight accompanied. ”
Prof van der Merwe has previously argued that many scientists were reluctant to consider the possibility that a lab leak started the pandemic for fear of having to curtail their own risky virus experiments.
He discovered that in a separate experiment in Germany, scientists were conducting tests similar to Imperial’s with the alpha and beta variants on hamsters, ferrets, and humanized mice.
The work, published in Nature, was led by Prof. Lorenz Ulrich, now at the Friedrich Loeffler Institute, Greifswald. It was co-authored by Christian Dorsten of Charité – Universität für Medizin Berlin, who signed a letter in the Lancet in 2020 dismissing the possibility that Covid-19 could have leaked from a laboratory.
‘There are more opportunities for recombination in animal studies and selection for more dangerous variants because they involve more cells that have been infected for longer periods of time,’ Prof van der Merwe added
“Handling animals is also more risky than handling cells in terms of transmission to the experimenter.”
He added: “None of these experiments help protect us from Sars-CoV-2.
“Obviously, if it were conclusively proven that the Sars-CoV-2 pandemic was the result of a laboratory leak, it would strengthen the case for tighter global regulation of experiments involving potentially dangerous pathogens.”
The UKHSA was contacted for comment but said it had nothing more to add on Imperial’s response. The Friedrich Loeffler Institute had not yet responded at the time of publication and the Charité – Universitätsmedizin Berlin declined to comment.