Professor Gerry Killeen, the AXA Research Chair in Applied Pathogen Ecology at University College Cork, said Ireland needs to copy Hong Kong, where 97% of people are wearing face masks.
He said face masks could have saved lives in recent months.
“I think there could be a lot of people still with us today if we had acted sooner,” he said.
The Cork-based scientist explained that, when people speak, they release droplets from their mouths which could contain the virus.
He said that wearing a mask is a way for the person wearing it to protect others from being exposed to it.
“They should be obligatory on the bus, on trains, on crowded streets, in shopping centres,” he said.
The UCC professor said he believed that children returning to playgrounds should also be wearing masks, and said they too could expose others to the virus when speaking.
“Children don’t go to the playground to be quiet, and they are just as susceptible to infection,” he added.