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

There is an increase in positive COVID-19 cases across the Bay Area, especially in San Francisco. UCSF's Dr. Monica Ghandi says it's because two new subvariants have come up this season. "The problem ...

Infections of COVID-19 are growing or likely growing in half of the U.S. as of July 8, according to CDC estimates.