
Why is COVID surging this summer? A doctor explains what to know and how to stay safe.
CBSN
It's not just President Biden who recently tested positive for COVID — cases of the virus are spiking across the country.
Nearly 40 states are reporting high COVID activity levels, according to data from the Centers for Disease Control and Prevention, and emergency room visits are at their highest for the virus since February.
Why the seemingly sudden summer surge? There are a couple of factors at play, Dr. Céline Gounder, CBS News medical contributor and editor-at-large for public health at KFF Health News, told "CBS Mornings" Wednesday.

Underwater archaeologist James Delgado reveals the stories behind history's most haunting shipwrecks
Renowned underwater archaeologist James Delgado appeared on "CBS Mornings" on Friday to discuss his new book, "The Great Museum of the Sea," and reflect on more than 50 years of searching for historic shipwrecks around the world.