Polio vaccine incidents reduced public confidence in polio vaccine leading to a drop in vaccination rates. At the same time that Salk was testing his vaccine, both Albert Sabin and Hilary Koprowski continued working on developing a vaccine using live virus. During a meeting in Stockholm to discuss polio vaccines in November 1955, Sabin presented results obtained on a group of 80 volunteers, while Koprowski read a paper detailing the findings of a trial enrolling 150 people. Sabin and Koprowski both eventually succeeded in developing vaccines. Because of the commitment to the Salk vaccine in America, Sabin and Koprowski both did their
Albert Sabin humanitarian benefit. Indeed, it was not clear to many that the vaccine was an American one, financed by U.S. dollars, as it was not widely available to ordinary Americans. Sabin also developed vaccines against other viral diseases, including encephalitis and dengue. In addition, he investigated possible links between viruses and some forms of cancer. In 1983, Sabin developed calcification of the cervical spine, which caused paralysis and intense pain. Sabin revealed in a television interview that the experience had made him decide to spend the rest of his life working on alleviating pain. This condition was successfully treated by surgery