COVID-19 appears to be on the rise in some parts of California as a new, highly contagious subvariant — featuring "razor blade throat" symptoms overseas — is becoming increasingly dominant.

A highly contagious new COVID variant is spreading across the United States. It's called NB.1.8.1, also known as Nimbus.

NB.1.8.1, a new COVID-19 variant that has caused concern among WHO officials, is now spreading in America, according to CDC data.