So far, 15 U.S. states have positive Nimbus cases, including Rhode Island, New York, Vermont, and Massachusetts.

That’s because the variant — NB.1.8.1. or “Nimbus” — may cause painful sore throats. The symptom has been identified by ...

The N.B.1.8.1 variant was first detected in January 2025. By the end of April, it was the dominant strain in both Hong Kong ...