Dr. Theresa Tam, head of the Public Health Agency of Canada, said today that Canadians can use non-medical masks in tandem with social distancing measures to limit the transmission of the deadly virus when out grocery shopping or at a pharmacy.
The recommendation represents an about-face for the public health officer — who until now has resisted the idea of non-health care professionals wearing masks.
"Wearing a non-medical mask is an additional measure that you can take to protect others around you," Tam said — while warning that a non-medical mask doesn't necessarily protect the person wearing it.
Tam has long maintained that masks should be reserved for the sick among us, and for doctors and nurses working in hospitals.
On Monday, however, Tam said wearing a mask can help prevent pre-symptomatic and asymptomatic people from inadvertently infecting others with COVID-19. She said the policy change comes in response to "emerging information" from the science and medical community.
She said Canadians shouldn't wear medical-grade masks like the N95, as those supplies have to be reserved for medical professionals.
The U.S. Centers for Disease Control and Protection (CDC) announced a similar policy shift over the weekend, saying that "new evidence" had led it to recommend that people wear cloth face coverings in public areas.
"We now know from recent studies that a significant portion of individuals with coronavirus lack symptoms ("asymptomatic") and that even those who eventually develop symptoms ("pre-symptomatic") can transmit the virus to others before showing symptoms," the agency said in a statement on its website.
"This means that the virus can spread between people interacting in close proximity — for example, speaking, coughing, or sneezing — even if those people are not exhibiting symptoms."
The CDC is recommending masks in settings where "other social distancing measures are difficult to maintain," such as grocery stores and pharmacies.
Both the Canada and U.S. health agencies have recommended people avoid crowded places and keep a distance of at least two arms' lengths — approximately two metres — from others as much as possible.