Monkeypox poses low risk to Canada, public health agency investigating about 20 cases

Canada's top public health officials say the risk posed by monkeypox is low, but nearly everyone in the country is susceptible because routine vaccination against smallpox ended decades ago.

The first two cases of the virus in Canada were confirmed in Quebec on Thursday, but chief public health officer Dr. Theresa Tam says a couple dozen possible cases are being investigated and the federal public health agency still does not know how widespread it might be.

Monkeypox is typically milder but in the same family of viruses as the now-eradicated smallpox, and can cause fever, headache, muscle aches, exhaustion, swollen lymph nodes and lesions.

The Public Health Agency of Canada says it is spread through prolonged close contact, including through direct contact with an infected person's respiratory droplets, bodily fluids or sores, and is not very contagious in a typical social setting.

There is global evidence that smallpox vaccines can offer protection against monkeypox, and Tam says Canada does maintain a small stockpile of doses in case of a biological incident.

Canada stopped routinely immunizing people against smallpox in 1972 and deputy chief public health officer Dr. Howard Njoo says that has left most people susceptible to monkeypox.