Should vaccinated people mask up with COVID-19 cases rising?
Yes. In places where the virus is surging, the U.S. Centers for Disease Control and Prevention recommends that vaccinated people return to wearing masks in public indoor places.
The CDC recently announced the updated guidance, citing new evidence that vaccinated people who get breakthrough infections could carry enough virus in their noses and throats to infect others.
COVID-19 vaccines greatly reduce the chance of severe illness and death and remain effective against variants, including the now predominant delta variant. But it's still possible to get infected.
Masking could prevent the spread of the virus to children too young for vaccination and people with weak immune systems.
In short, the vaccine protects you. A mask protects others in case you are carrying the virus without knowing it.