Information - Public Health Agency of Canada Recommendations on use of Masks in Public Settings to Prevent Transmission of the H1N1 Flu Virus (Human Swine Flu)

May 2009

The current outbreak of H1N1 flu virus (human swine flu) is receiving a great deal of media coverage. Recent news broadcasts and stories feature pictures and videos showing people wearing surgical masks in public. As a result, Canadians are asking whether they should wear surgical masks in order to protect themselves or their families from infection. It's important that everyone has accurate information on this issue.

The Public Health Agency of Canada does not recommend that healthy people wear masks as they go about their daily lives in the community.

There is no evidence to suggest that wearing masks will prevent the spread of infection in the general population. Improper use of masks may in fact increase the risk of infection.  Masks do not act as an effective barrier against disease when they are worn for extended periods of time. In addition, removing your mask incorrectly can spread virus to your hands and face.

As Canada's Chief Public Health Officer, Dr. David Butler-Jones, has said it can be easy to get a false sense of security from wearing the mask, and forget about the importance of the basic infection control practices, like washing hands, covering coughs and sneezes, avoiding close contact with people who are sick, and staying home when sick. These simple practices are the most important in preventing the transmission of influenza.

The situation is different for a person who is ill and who must go out into the community (for example, to seek medical care). In that case, it is recommended taking measures to avoid exposing others to the virus, such as coughing or sneezing into a disposable tissue or sleeve, and avoiding crowds (like mass transit). A face mask should then be worn, if available, to reduce the risk of spreading the virus within the community.