Search for "vaccination"

Vaccination is the introduction of a vaccine into the body to produce immunity to a disease. Vaccine hesitancy is the refusal or delayed acceptance of vaccination due to fears or anxiety about vaccines. It includes a range of concerns such as uncertainty about vaccines’ contents and their safety and the belief that vaccines are responsible for causing other medical conditions (e.g., autism). Other factors include opposition to state control and infringement on individual liberty, suspicions about the pharmaceutical industry and a declining faith in science and medicine. In Canada, as in other wealthy countries, vaccine hesitancy has increased in recent years.

Leone Norwood Farrell, biochemist and microbiologist (born 13 April 1904 in Monkland, Ontario; died 24 September 1986 in Toronto). Farrell was a pioneer in the development of vaccines. Most notably, her “Toronto Method” made possible the large-scale production of the Salk polio vaccine in the early 1950s. Farrell’s polio vaccine work followed innovations in the production of pertussis (whooping cough) vaccine, as well as penicillin.

From April to December 2009, Canada experienced an outbreak of influenza A (H1N1). The virus began in North America and spread to many other countries in a global pandemic. This new type of flu differed from the typical seasonal flu, and its effects were more severe. Worldwide, more than 18,000 people are confirmed to have died of H1N1, including 428 Canadians. Estimates based on statistical models have put global deaths much higher. Totals may have been in the hundreds of thousands. The H1N1 pandemic tested Canada’s improvements to its public health system after the SARS outbreak of 2003. On the whole, it revealed a more efficient, coordinated response.

Click here for definitions of key terms used in this article.

During the first half of the 20th century, poliomyelitis, a.k.a. polio or “The Crippler,” hit Canada harder than anywhere else. Successive polio epidemics peaked in a national crisis in 1953. By that time, however, scientists at Connaught Medical Research Laboratories of the University of Toronto had made key discoveries that enabled American medical researcher and virologist Jonas Salk to prepare the first polio vaccine. Connaught Labs also solved the problem of producing the vaccine on a large scale. Canada went on to play an important role in the development of the oral polio vaccine and international efforts to eradicate the disease.

Click here for definitions of key terms used in this article.

Smallpox is an infectious disease caused by the variola virus. The disease arrived in what is now Canada with French settlers in the early 17th century. Indigenous people had no immunity to smallpox, resulting in devastating infection and death rates. In 1768, arm-to-arm inoculation became more widely practised in North America. By 1800, advances in vaccination helped control the spread of smallpox. Public health efforts also reduced rates of infection. In the 20th century, Canadian scientists helped the World Health Organization eradicate smallpox. Eradication was achieved in 1979, but virus stocks still exist for research and safety reasons.

Click here for definitions of key terms used in this article.