Nearly 1 in 10 new COVID-19 cases in the U.S. are from the BA.2.86 variant, the Centers for Disease Control and Prevention estimated Monday, nearly triple what the agency estimated the highly mutated variant’s prevalence was two weeks ago.
Among the handful of regions with enough specimens reported from testing laboratories, BA.2.86’s prevalence is largest in the Northeast: 13.1% of cases in the New York and New Jersey region are blamed on the strain.
Monday’s figures mark the first time BA.2.86’s prevalence has surged enough to be listed as a standalone variant on the CDC’s estimates. Scientists first warned of the highly mutated strain’s discovery over the summer.
“In previous Nowcast updates, BA.2.86 was too uncommon to be shown separately and was grouped with other BA.2 strains,” the CDC said Monday.
Before this point, officials have said the vast majority of new COVID-19 cases have been blamed on the XBB variant and a crowd of XBB’s closely related descendants. Those include the HV.1 and EG.5 variants that are currently predominant nationwide.
The CDC’s estimates carry wide margins of error around BA.2.86’s prevalence. As little as 4.8% or as much as 15.2% of circulating SARS-CoV-2 could be from BA.2.86, the agency says.