Poliomyelitis leading to large-scale trials in the then Belgian Congo and the vaccination of seven million children in Poland against serotypes PV1 and PV3 between 1958 and 1960. The second inactivated polio virus vaccine was developed in 1952 by Jonas Salk at the University of Pittsburgh, and announced to the world on 12 April 1955. The Salk vaccine, or inactivated poliovirus vaccine, is based on poliovirus grown in a type of monkey kidney tissue culture (vero cell line), which is chemically inactivated with formalin. After two doses of inactivated poliovirus vaccine (given by injection), 90 percent or more of individuals develop
Jonas Salk their parents. ... From these ranks, of the 1930s and 1940s, emerged a wealth of intellectual talent, including more Nobel Prize winners—eight—and PhD recipients than any other public college except the University of California at Berkeley." Salk entered CCNY at the age of 15, a "common age for a freshman who had skipped multiple grades along the way." As a child, Salk did not show any interest in medicine or science in general. He said in an interview with the Academy of Achievement, "As a child I was not interested in science. I was merely interested in things human, the