Health officials in Canada have changed course and are now saying that wearing face masks can help control the spread of COVID-19. Dr. Theresa Tam - Canada's chief public health officer - has been reluctant to recommend masks - up until now. To advise on what masks can - and can't - do to help in this pandemic Russell contacted Jason Kindrachuk, an Assistant Professor and Canada Research Chair in the Department of Medical Microbiology and Infectious Diseases at the University of Manitoba.