Jonas Salk vaccine. A few weeks later, Salk injected children at the Polk State School for the retarded and feeble-minded. In 1954 he tested the vaccine on about one million children, known as the polio pioneers. The vaccine was announced as safe on April 12, 1955. The project became large, involving 100 million contributors to the March of Dimes, and 7 million volunteers. The foundation allowed itself to go into debt to finance the final research required to develop the Salk vaccine. Salk worked incessantly for two and a half years. Salk's inactivated polio vaccine was the first vaccine for the disease;
Jonas Salk got in. During his years at New York University Medical School, Salk worked as a laboratory technician during the school year and as a camp counselor in the summer. During Salk's medical studies, he stood out from his peers, according to Bookchin, "not just because of his continued academic prowess—he was Alpha Omega Alpha, the Phi Beta Kappa Society of medical education—but because he had decided he did not want to practice medicine." Instead, he became absorbed in research, even taking a year off to study biochemistry. He later focused more of his studies on bacteriology which had replaced medicine