US public health officials have recommended that vaccinated people in areas with “substantial” levels of Covid-19 start wearing masks again in indoor public places, reversing guidance issued two months ago amid the rapid spread of the contagious Delta variant.
The US Centers for Disease Control and Prevention issued its revised mask guidance on Tuesday, as President Joe Biden said he was considering requiring all federal government employees be vaccinated, reflecting growing alarm about the spread of the new strain.
Rochelle Walensky, the CDC director, said the Delta strain was “uniquely different” from previous variants, adding: “This new science is worrisome and unfortunately warrants an update.”