COVID-19 cases are rising in half of U.S. states. What to know about COVID trends and the new Stratus and Nimbus variants.

Public health officials are sounding the alarm as an outbreak that began in China has now infected thousands of people in ...

A contagious new COVID-19 variant called NB.1.8.1, aka "Nimbus," is now dominant in the United States, CDC data show. What to ...