Vaccine trial stages that collect information continuously on vaccine usage, adverse effects, and long-term immunity. Vaccine trials may take months or years to complete, since a sufficient time period must elapse for the subjects to react to the vaccine and develop the required antibodies. Poliomyelitis, a viral disease, has the potential to damage the central nervous system and leave children paralyzed. Jonas Salk developed an attenuated vaccine to combat the rising prevalence of the disease around the world. In 1955 the results from the preliminary trial of Salk’s vaccine were announced to the general public and within 2 hours it was licensed.
Jonas Salk as his primary interest. He said his desire was to help humankind in general rather than single patients. "It was the laboratory work, in particular, that gave new direction to his life." According to Salk: "My intention was to go to medical school, and then become a medical scientist. I did not intend to practice medicine, although in medical school, and in my internship, I did all the things that were necessary to qualify me in that regard. I had opportunities along the way to drop the idea of medicine and go into science. At one point at the end