GENEVA (AP) -- The World Health Organization is citing "some evidence" that wearing face masks - if used improperly - could actually do more harm than good in the fight against the spread of the coronavirus.
WHO emergencies chief Dr. Michael Ryan said he was unaware of a move by officials in Austria to require people to wear face masks when they go to supermarkets.
With some countries facing shortages of masks, Ryan reiterated that WHO believes generally they should be worn by people who are ill, to prevent them from spreading the virus, and by health care workers who really need them.
"But there is no specific evidence to suggest that the wearing of masks by the mass population has any particular benefit - in fact, there's some evidence to suggest the opposite," he said.
Ryan didn't elaborate beyond citing "risks" linked to fitting masks properly, though he appeared to be alluding to how hands can carry virus up to or neaer the face as the masks are put on.