A

SALK, JONAS E. 1914-

VROLOGÍST WHO DEVELOPED THE FIRST WIDELY ADMINISTERED POLIO VACCINE

Medical Hero

Jonas Salk was propelled into worldwide acclaim for his development of the first successful long-term vaccine against polio. Although the Salk polio vaccine achieved incomplete immunity and was completely replaced within a decade, Americans in the mid 1950s viewed Salk as a hero in the battle against a disease that had crippled a president (Franklin Delano Roosevelt) and shortened or restricted tens of thousands of young lives.

Director of Virus Research

When the University of Pittsburgh School of Medicine expanded its Virus Research Laboratory in 1947, the thirty-three-year-old Salk was named its director. During the course of a three-year project funded by the National Foundation for Infantile Paralysis, he demonstrated the existence of three types of polio virus and concluded that a vaccine must immunize against all of them to be effective.

Salk and the NFIP

Salk developed a close relationship with NFIP director Basil O'Connor, who came to regard him with almost fatherly affection. After developing a technique introduced in 1949 for cultivating polio virus in nonnervous tissues, Salk, with O'Connor's assent, began working on a vaccine against polio using dead viruses suspended in mineral oil and formaldehyde.

Success with Dead Viruses

Researchers hotly debated the virtues of a dead-virus vaccine versus a vaccine using attenuated, or weakened, virus. The consensus in the early 1950s was that an attenuated vaccine would require more time to develop and might be risky to use; therefore, O'Connor devoted the private funding of the NFIP to Salk.

Trials of the Salk vaccine in 1953 and 1954 were successful, and the mass immunization of American children began in 1955.