An Epidemiologist Breaks Down How New Mask Guidance Applies To Mass.

As coronavirus cases rise, The Centers for Disease Control and Prevention is recommending that vaccinated people start wearing masks indoors some times.

The recommendation applies to areas considered to have a "high and substantial transmission" of COVID-19, and in K-12 schools.

To talk about how this applies to Massachusetts, WBUR's Morning Edition was joined by Dr. Shira Doron, an infectious disease physician and hospital epidemiologist at Tufts Medical Center.