"We were told in one lecture that it was possible to immunize against diphtheria and tetanus by the use of chemically treated toxins, or toxoids. And the following lecture, we were told that for immunization against a virus disease, you have to experience the infection, and that you could not induce immunity with the so-called "killed" or inactivated, chemically treated virus preparation. Well, somehow, that struck me. What struck me was that both statements couldn't be true. And I asked why this was so, and the answer that was given was in a sense, "Because." There was no satisfactory answer."
Jonas Salk was still a student when he began to look for a better answer to his classroom question, and the answer he found led to one of the most dramatic breakthroughs in the history of medicine.
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. That 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.
Salk went on to found the Jonas Salk Institute for Biological Studies in La Jolla, California, where he continued his research into the causes, prevention and cure of diseases such as cancer and AIDS. Dr. Salk never patented his polio vaccine, but distributed the formula freely, so the whole world could benefit from his discovery.