The new sub-variant of Omicron BA.2.75, renamed by social networks ‘Centaurus’, is no more resistant to our antibodies than the currently dominant Omicron 5 variant. This is what emerges from a study by the Karolinska Institutet, in Sweden, published in the ‘Lancet infectious diseases’: evidence considered “very positive” and “very reassuring” by researchers because this means that in the event of a wave of this sub-variant, no escapes the antibodies developed with Omicron 5.
In fact, the study wanted to test the ability of ‘Centaurus’ – detected last May in India where it has spread widely, and then ‘reach’ other countries in the world, including Sweden, where it was studied by researchers from Karolinska. “Identifying how vulnerable the population is right now to emerging variants is critical,” says Daniel Sheward, researcher in the Department of Microbiology, Cancer and Cell Biology, Karolinska Institutet, and first author of the study. “By producing a pseudovirus for BA.2.75, we were able to test its sensitivity to antibodies present in blood donors.” The tests were carried out using 40 blood samples collected at random in Stockholm, both before and after the first Omicron wave.
“Our study shows that Omicron BA.2.75 has approximately the same level of antibody resistance as the dominant variant BA.5, which is reassuring news if we were to experience a BA.2.75 surge in Sweden,” says Ben Murrell , from the same Department of the Karolinska Institutet, and senior author of the study.
Researchers from the Karolinska Institutet, in collaboration with the University of Cape Town, South Africa, Eth Zurich, Karolinska university hospital and Imperial College London, also evaluated whether monoclonal antibodies, used to treat patients already infected, they lose their effect against ‘Centaurus’ compared to Omicron 5: and even in this case no alarming differences were found.
The Swedish researchers – the study reads – will continue to monitor the new mutations occurring in Omicron’s underlines that could ‘threaten’ the effectiveness of vaccines. The study was funded by SciLifeLab’s Pandemic laboratory preparedness program, the Erling persson Foundation, the European Union’s Horizon 2020 research and innovation program.