Maybe if the burka is thick enough,(like the Saudi women, who are covered head to toes with a screen to see through) but an illness spread by droplets, which covid19 does, needs people to be close enough to each other to breathe in the droplets. If a whole family shelters together, they’d need masks and distancing when going out.

Similar to nun’s habits: most only cover the hair, and sometimes the neck. Same risk as a non-nun.

If I had to be out and about, that Saudi outfit would seem safe, if I didn’t have access to PPE.