From the early 1900s, researchers pursued two different kinds of polio vaccine. One used inactivated (killed) viruses. The other kind used live but attenuated, or weakened, virus. Jonas Salk was the leading proponent of the killed virus and Albert Sabin became the foremost proponent of the attenuated virus approach.
|At its peak incidence in the early 1950s, poliomyelitis occurred at a rate of 13.6 cases per 100,000 population. The incidence of cancer today, by comparison is 566.1 per 100,000.|
|Edward Jenner created the first successful vaccination for a disease—smallpox—in 1796. At the time of the polio clinical trials, there were three widely used vaccines: for yellow fever (1937), rabies (1885), and smallpox. Today there are over 300 vaccines for about thirty different diseases.|
|There are two kinds of polio vaccine. IPV (Salk’s) is an injected shot used today primarily in the United States and Europe. OPV (Sabin’s) is given orally in drop form and used in global efforts to stop polio transmission.|
The Salk Vaccine
Results of trials with small numbers of children in 1952 encouraged the National Foundation for Infantile Paralysis to adopt Salk’s vaccine for a large-scale trial in 1954. Salk called his vaccine “Pittsburgh vaccine,” but reporters named it “Salk.”