COVID-19 Variant NB.1.8.1 (“Nimbus”): Global Spread and Characteristics
COVID-19 Variant NB.1.8.1 (“Nimbus”): Global Spread and Characteristics A new COVID-19 variant, NB.1.8.1, also known as “Nimbus,” is spreading globally. As of mid-May 2025, it comprised nearly 11% of sequenced samples reported worldwide. In the United States, it accounted for approximately one-third of COVID-19 cases. The variant has been detected in travelers arriving in the U.S. from the eastern Mediterranean, Southeast Asia, and western Pacific regions, with cases confirmed in California, Washington state, Virginia, and New York. First identified in…