New study suggests healthcare workers should wear N95 masks when respiratory infections are high.

Wearing an N95 reduced viruses in exhaled breath by 98% vs ~70% for surgical masks.

Two new Canadian studies demonstrating the efficacy of masks.

These studies show that mandatory masking, esp during periods of high respiratory viruses in the community, can result in reductions in absenteeism, prevent infections and deaths & reduce economic burden. 🧵 1/9