Jean-Benoit Legault, The Canadian Press
MONTREAL — A virus that combines features of the original SARS-CoV-2 and the Omicron variant has killed 80% of mice it has been administered to, in work that is causing some consternation in the scientific community.
Boston University researchers created this hybrid version of the coronavirus in the lab by adding the Omicron variant spike protein (which is known to be highly effective at infecting human cells) to the Wuhan strain of the coronavirus.
“In K18-hACE2 mice, while Omicron causes mild, non-fatal infection, the virus (with the Omicron spike protein) causes severe disease with an 80% mortality rate,” the authors write. American researchers in a study that has not yet been peer-reviewed.
In particular, the hybrid virus would have caused a more severe infection in the lungs of the mice than the Omicron variant. Compared to the 80% mortality rate, all mice infected with the Omicron variant survived.
The work was carried out at Boston University’s National Laboratories for Emerging Infectious Diseases, Level 4 facilities designed to safely study viruses as dangerous as Ebola.
Despite this, several experts question the wisdom and relevance of such experiments, recalling among other things that it cannot be ruled out that a leak at the Wuhan Institute of Virology is at the origin of the pandemic. Others even wonder if these works somehow violate US law.
“These researchers did not intend to create a new dangerous virus, which would be ethically unacceptable, commented in an email Professor Denis Leclerc, from the department of microbiology-infectiology and immunology of the Faculty of Medicine of the University. ‘Laval University. They just wanted to study the pathogenicity of a recombinant virus that might appear in the population. They obtained a surprising result, which arouses interest and which will attract the attention of several other researchers.”
This experiment, he adds, allows us to understand a little better what might happen if ever the S protein of the Omicron variant were to, by recombination, end up in another context, he added.
Such studies “might be used to predict an event that might eventually occur in the population in order to better prepare,” explained Professor Leclerc.
However, we must not lose sight of the fact that these experiments were carried out on mice, and that these results are not necessarily applicable to humans, he specifies.
“But it can provide leads to guide our research in the population and perhaps be able to more easily predict the emergence of more dangerous strains,” concluded Professor Leclerc.
