Pfizer says its Covid-19 vaccine protects younger teens

Pfizer announced Wednesday that its Covid-19 vaccine is safe and strongly protective in kids as young as 12, a step toward possibly beginning shots in this age group before they head back to school in the fall. ​​​Most Covid-19 vaccines being rolled out worldwide are for adults, who are at higher risk from the coronavirus. Pfizer's vaccine is authorized for ages 16 and older.