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The Boston University laboratory combined the genome of the original Covid-19 virus with part of the Omicron variant to try to determine what allows this strain to more easily escape the immunity conferred by vaccination. This technique, which may seem questionable, has led to a torrent of controversy and an investigation by US health authorities, which was confirmed on Wednesday.
Scientists at Boston University surely did not expect this. Accused by sensational media of having created a “more deadly” strain of Covid-19, their laboratory is now the subject of an investigation by health authorities, the existence of which was confirmed to the Financial Times on Wednesday, October 19. Reluctantly, they also rekindled the ardor of conspiracy theorists for whom the Sars-Cov-2 virus was, in reality, a human creation in a laboratory in Wuhan.
It all started with a study published the previous week which “turns out to be rather important for our understanding of how the virus works”, assures Lawrence Young, virologist at the medical school of the University of Warwick. These American researchers demonstrate that the mutations of the famous Spike protein of Sars-CoV-2 [la pointe du virus qui lui sert à s’accrocher aux cellules pour les infecter, NDLR] allow the Omicron variant – currently dominant in the world – to thwart vaccine immunity more easily, but that it is not these changes “that have made this strain less virulent than the original virus”, summarizes Lawrence Young. Two conclusions that had not yet been scientifically demonstrated.
Genetically modified mice
But what does drunkenness matter, as long as you can question the bottle. Because the laboratory used a method that may surprise to carry out its experiment. The scientists combined the genome of the original strain of Covid-19 with the spike protein of the Omicron variant. As a result, they developed an artificial mutant of the Sars-Cov-2 virus in the laboratory.
They then infected laboratory mice to find that 80% of the rodents thus exposed to the disease had perished. It did not take more for the British tabloid The Daily Mail to draw an article entitled “Scientists have created a new strain of Covid-19 which kills 80%”.
Enough to ensure the virality of the article on social networks… A lethality rate of 80% would be enough to propel this variant into the yard of the most deadly viruses, such as Ebola. The success was above all immediate in the conspiratorial nebula on the Net. “It is sure that the idea of a virus developed by man in the laboratory had something to seduce the followers of the conspiracy theory according to which the Covid-19 was manufactured by Chinese scientists in the laboratory of Wuhan” , notes Lawrence Young.
The sensational Daily Mail article prompted an outraged reaction from Boston University, which in a statement denounced “false and inaccurate” allegations.
The experience of American researchers would not have resulted in the creation of a more deadly variant. Indeed, “this ‘chimeric’ strain [c’est-à-dire qui n’existe pas dans la nature] was administered to mice which were made particularly sensitive to the effects of Covid-19”, underlines Lawrence Young. Thus 100% of these same mammals made more fragile in the face of the disease succumbed to the effects of the original strain of Sars -Cov-2, against 80% of mice exposed to the hybrid variant.Hence the assertion of Boston University that the Daily Mail article was misleading and that the hybrid strain was, ultimately, less dangerous than the original virus.
Dangerous “gain of function”?
The American researchers hoped that the controversy would stop there. But the National Institutes of Health (NIH), the main American public organization supporting medical research, then launched an investigation to determine whether the Boston laboratory was at fault by not asking for its authorization to conduct its experiment.
In question this time: the fact of playing the alchemists of virology by combining two strains to create a new one. A method above which floats the specter of “gain of function”. “It is a very important and often used process in genetics which consists of artificially adding characteristics to a gene to study the reaction. Its use in virology, just as relevant in my opinion, has always been more controversial”, summarizes Lawrence Young .
These detractors worry about human manipulation which would result in transforming a pathogenic agent into a deadly virus and/or capable of triggering pandemics. This fear is recent: it dates back to 2012 and a scientific article relating to “gain of function” work carried out on the influenza virus, recalls the site of the scientific journal Nature.
“Most of the debate revolves around this virus and what would happen if someone tried to recreate the Spanish flu to study it or mixed it with elements of smallpox”, specifies Luke Young.
He acknowledges that the risk of a laboratory accident resulting in the release of a dangerous man-made virus into the wild is not to be taken lightly. “That’s why you have to apply draconian security procedures, and that’s what Boston University seems to have done,” said the British virologist.
The researchers from the American laboratory thus used a security level 3 laboratory – that is to say just below the military security system in place in the few research centers authorized to handle the most dangerous pathogens (such as than the Wuhan laboratory) – to carry out their work. They are also not the only ones to have used this technique to study Sars-CoV-2 since Chinese scientists published in September the results of work involving mixtures of the original strain with elements of most variants known to date, recalls the daily Liberation.
Further, Boston University disputes that the published work involves a “gain of function” and argues that the green light obtained from the university’s internal biosafety committee was sufficient.
For her, there is no gain of function because the experiment “did not amplify the original strain of Sars-CoV-2 nor did it make it more dangerous”. A very restrictive definition of this concept since it only takes into account the result of the study. This is the door open to all hybridizations since one can never be sure in advance of the outcome of a manipulation.
But nothing prevents Boston University from accepting this interpretation either. “There is currently no consensus definition,” explains Luke Young.
However, he believes that if in doubt, the researchers should have informed the NIH. Especially “as the activities of this laboratory are partly financed by this organization which, as a result, may, according to American regulations, be required to give its agreement” on experiments requiring special security measures, details Luke Young.
“It is therefore above all a story of bureaucratic error”, adds this expert. The risk, according to him, is that in the heated context of the discussions around the Covid-19, such a case would damage an otherwise very useful research technique. After all, Astrazeneca-Oxford’s Covid-19 vaccine is based on a similar approach since it contains the genome of a common virus to which an ounce of Sars-CoV-2 has been added to stimulate the immune system to manufacture the right antibodies.