Technological and industrial history of 20th-century Canada Blood tests would become increasingly sophisticated in the coming years. The electroencephalograph, used for the diagnosis of neurological disorders was introduced in major Canadian medical institutions in the late forties. The techniques for the mass production and distribution of vaccines and for the mass public inoculation were introduced during these years. Polio was a disease that affected large numbers of Canadian children during the first part of the 20th century. In the US, research by Dr. Jonas Salk in the late 1940s led to the discovery of vaccine for the prevention of this disease. However, there was no technique for
Jonas Salk the University of Michigan. Francis had recently joined the faculty of the medical school after working for the Rockefeller Foundation, where he had discovered the type B influenza virus. According to Bookchin, "the two-month stint in Francis's lab was Salk's first introduction to the world of virology—and he was hooked." After graduating from medical school, Salk began his residency at New York's prestigious Mount Sinai Hospital, where he again worked in Francis's laboratory. In 1947, Salk became ambitious for his own lab and was granted one at the University of Pittsburgh School of Medicine, but the lab was smaller than