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
Lee Salk his older brother. Salk attended the University of Michigan. Salk's published work investigated the effect of retirement on mortality, the effect of the mother's heartbeat on the newborn, and the relationship between adverse maternal and perinatal conditions and later self-destructive behavior. He was the author of eight books. Salk was married twice, first to Kerstin and then Mary Jane. He had two children from his first marriage, a son Eric and daughter Pia. Salk developed cancer and died in hospital in Manhattan at age 65 on May 2, 1992. Salk was a professor at Cornell University Medical Center. Lee Salk