Researchers in Sweden found that BA.2.75.2, a sub-linage of Omicron can evade the majority of neutralizing antibodies in the body, and is also resistant to several monoclonal antibody antiviral treatments.
The variant BA.2.75.2, is one of the latest developments in the Omicron lineage of COVID-19. According to CTV News Canada, researchers say it is popping up in other variants as the virus continues to expand and evolve.
These findings were published in the Lancet Infectious Diseases on Thursday. The researchers looked at three Omicron subvariants and found that while vaccines still provide some protection against them, certain variants are better than others at escaping antibodies.
The study shows that antibodies in random serum samples from 75 blood donors in Stockholm were approximately only one-sixth as effective at neutralizing BA.2.75.2 compared with the now-dominant variant BA.5.
“While antibody immunity is not completely gone, BA.2.75.2 exhibited far more dramatic resistance than variants we’ve previously studied, largely driven by two mutations in the receptor binding domain of the spike protein,” says Ben Murrell, the Study’s Corresponding Author, Assistant Professor, Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet
Only one of the clinically available monoclonal antibody treatments that were tested, bebtelovimab, was able to potently neutralize the new variant, according to the study. Monoclonal antibodies are used as antiviral treatments for people at high risk of developing severe COVID-19.
BA.2.75.2 is a mutated version of another Omicron variant, BA.2.75. Since it was first discovered earlier this fall, it has spread to several countries but so far represents only a minority of registered cases.
In the United States, the omicron BA.5 variant remains dominant in the country, but it is starting to lose some ground to other versions of the virus, according to data from the Centers for Disease Control and Prevention published on Friday.
About 3 percent of new infections are attributable to BA.2.75. and BA.2.75.2, which are related to the omicron BA.2 variant that caused a bump in cases during the spring but was pushed out.
According to the most recent data from the Public Health Agency of Canada, BA.5 and BA.4 are currently dominating in Canada.
While BA.2.75.2 represents a minority of cases right now, there are fears that because of its additional mutations, this could potentially make it more infectious.
