Cold War tensions and the polio vaccine Sabin vaccine from the Soviet side. However other Soviet virologists argued that the Salk vaccine could be considered safe, since the Americans tested it on their own people. They considered that the Sabin vaccine must be potentially dangerous because the Americans did not wish to test it on their own society. The documented achievement of the Sabin-Chumakov collaboration eventually trumped the ideological differences of the Cold War. Their oral live-virus vaccine became federally licensed in 1962, and used for over three decades to help eliminate polio globally, replacing the Salk vaccine. Using these vaccines, the threat of polio remains only
Jonas Salk austere", wrote "The New York Times", "Salk the man is a person of great warmth and tremendous enthusiasm. People who meet him generally like him." A Washington newspaper correspondent commented, "He could sell me the Brooklyn Bridge, and I never bought anything before." Award-winning geneticist Walter Nelson-Rees called him "a renaissance scientist: brilliant, sophisticated, driven ... a fantastic creature." He enjoys talking to people he likes, and "he likes a lot of people", wrote the "Times". "He talks quickly, articulately, and often in complete paragraphs." And "He has very little perceptible interest in the things that interest most people—such as