"Any threat around the world is a threat to us all," says infectious disease expert
As the rate of vaccination slows in the U.S., other countries around the world are facing renewed COVID-19 crises. CBS News correspondent Meg Oliver reports on the U.S. vaccine surplus, and infectious disease physician Dr. Mati Hlatshwayo Davis joins CBSN to explain why richer countries need to help other nations for everyone's benefit.