A variant nicknamed “Fornax,” officially FL.1.5.1, is the next largest at 14.5% of US infections and represents a growing share of East Coast cases. A wide range of other variants account for smaller shares of the total, with BA.2.86 less than 1%.
Dr David Dowdy, an infectious disease epidemiologist at Johns Hopkins Bloomberg School of Public Health, believes FL.1.5.1 will become the predominant variant in the coming months, but he does not expect an infection wave like the one driven by Omicron last winter.
Dowdy suggested the surge in cases may be due to immunity from vaccination and infection wearing off since the last surge.
What do scientists say about BA.2.86?
Scientists have been keeping an eye on BA.2.86 because it carries more than 35 mutations in key portions of the virus compared to XBB.1.5, the dominant variant through most of 2023.
The dramatic changes — on par with the genetic shift seen in the Omicron variant compared with its Delta predecessor — raised concerns the new variant could cause a major surge.
Experiments testing versions of the virus in two US independent laboratories suggest that is unlikely, said Dr Dan Barouch, director of the Centre for Virology and Vaccine Research at Beth Israel Deaconess Medical Centre in Boston, whose lab led one of the studies.
