In America in the 1950s, summertime was a time of fear and anxiety for many parents; this was the season when children by the thousands became infected with the crippling disease poliomyelitis, or polio. This burden of fear was lifted forever when it was announced that Dr. Jonas Salk had developed a vaccine against the disease. Salk became world-famous overnight, but his discovery was the result of many years of painstaking research.

Jonas Salk was born in New York City. His parents were Russian-Jewish immigrants who, although they themselves lacked formal education, were determined to see their children succeed, and encouraged them to study hard. Jonas Salk was the first member of his family to go to college. He entered the City College of New York intending to study law, but soon became intrigued by medical science.

While attending medical school at New York University, Salk was invited to spend a year researching influenza. The virus that causes flu had only recently been discovered and the young Salk was eager to learn if the virus could be deprived of its ability to infect, while still giving immunity to the illness. Salk succeeded in this attempt, which became the basis of his later work on polio.

After completing medical school and his internship, Salk returned to the study of influenza, the flu virus. World War II had begun, and public health experts feared a replay of the flu epidemic that had killed millions in the wake of the First World War. The development of vaccines controlled the spread of flu after the war and the epidemic of 1919 did not recur.

In 1947, Salk accepted an appointment to the University of Pittsburgh Medical School. While working there, with the National Foundation for Infantile Paralysis, Salk saw an opportunity to develop a vaccine against polio, and devoted himself to this work for the next eight years.

In 1955 Salk's years of research paid off. Human trials of the polio vaccine effectively protected the subject from the polio virus. When news of the discovery was made public on April 12, 1955, Salk was hailed as a miracle worker. He further endeared himself to the public by refusing to patent the vaccine. He had no desire to profit personally from the discovery, but merely wished to see the vaccine disseminated as widely as possible.

Salk's vaccine was composed of "killed" polio virus, which retained the ability to immunize without running the risk of infecting the patient. A few years later, a vaccine made from live polio virus was developed, which could be administered orally, while Salk's vaccine required injection. Further, there was some evidence that the "killed" vaccine failed to completely immunize the patient. In the U.S., public health authorities elected to distribute the "live" oral vaccine instead of Salk's. Tragically, the preparation of live virus infected some patients with the disease, rather than immunizing them. Since the introduction of the original vaccine, the few new cases of polio reported in the United States were probably caused by the "live" vaccine which was intended to prevent them. In countries where Salk's vaccine has remained in use, the disease has been virtually eradicated.

In 1963, Salk founded the Jonas Salk Institute for Biological Studies, an innovative center for medical and scientific research. Jonas Salk continued to conduct research and publish books, some written in collaboration with one or more of his sons, who are also medical scientists.

Salk's published books include Man Unfolding (1972), The Survival of the Wisest (1973), World Population and Human Values: A New Reality (1981), and Anatomy of Reality (1983).

Dr. Salk's last years were spent searching for a vaccine against AIDS. Jonas Salk died on June 23, 1995. He was 80 years old.