Jonas Salk

Jonas Salk was born on October 28, 1914, in New York City to immigrant Jewish parents and pursued medicine amid the Great Depression, earning his M.D. from New York University College of Medicine in 1939. Early in his career, he worked with mentor Thomas Francis Jr. on killed-virus immunology, contributing to an influenza vaccine during World War II at the University of Michigan School of Public Health. In 1947, Salk joined the University of Pittsburgh School of Medicine as director of the Virus Research Laboratory, funded by the National Foundation for Infantile Paralysis (now March of Dimes). There, Salk focused on poliomyelitis, a devastating disease causing widespread paralysis and thousands of deaths annually, with 58,000 U.S. cases in 1952 alone. Challenging prevailing views that only live attenuated viruses could vaccinate effectively, Salk developed a killed-virus polio vaccine using formaldehyde-inactivated strains of all three poliovirus types grown in monkey kidney cells. He began human trials in 1952 on recovered patients and healthy individuals, including himself, his wife, and children, confirming antibody production without illness. The pivotal 1954 field trial, directed by Francis, involved 1.8 million children dubbed 'Polio Pioneers,' demonstrating the vaccine's safety and 90% effectiveness. Announced on April 12, 1955, it led to rapid U.S. production by companies like Eli Lilly and a sharp decline in cases. Post-vaccine, Salk founded the Salk Institute for Biological Studies in 1963 in La Jolla, California, advancing virology and biological research, and continued exploring vaccines and multiple sclerosis until his death on June 23, 1995.