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
David Bruce (microbiologist) discouraged the experiments being carried by Zammit, and doubted his ability as a microbiologist. Eventually, when he learned of the positive results linking the fever with unpasteurized goat milk, Bruce tried to discredit the role of Zammit and take credit to himself. To a certain extent he succeeded, as it was renamed after him as brucellosis, however information about the role of Zammit has eventually surfaced. When he was transferred to South Africa, Bruce was sent to Zululand in 1894 to investigate the outbreak of cattle disease which the native called "nagana". In 1903, he identified the causative protozoan, and