COVID-19 omicron strain BA.2.86 is now a variant of interest after nearly tripling in prevalence.
Between Oct. 28 and Nov. 11, BA.2.86 accounted for 3% of confirmed COVID-19 cases in the U.S., according to the CDC. Over the following two weeks, the variant grew to 8.8% of cases.
During this change, the World Health Organization named it a variant of concern Nov. 21 after "a slow but steady increase in the proportion of BA.2.86 reported," the WHO said. A substantial increase happened globally in October, when its prevalence grew from 1.8% to 8.9%.
BA.2.86 is not an offshoot of XBB, which the latest COVID-19 vaccines are targeting, but the FDA said Nov. 27 the "public health risk posed by this variant is low." The two leading variants, HV.1 and EG.5, are XBB offshoots and account for 31.7% and 13.1% of infections, respectively.
The WHO said BA.2.86 does not seem to be more evasive than other circulating variants, and current data indicates it does not cause more severe cases than other omicron variants.
The FDA projects BA.2.86 and its offshoots, such as JN.1, will increase in proportion over the next few weeks.