Jonas Salk laboratory. He later joined the National Foundation for Infantile Paralysis's polio project established by President Franklin D. Roosevelt. Extensive publicity and fear of polio led to much increased funding, $67 million by 1955, but research continued on dangerous live vaccines. Salk decided to use the safer 'killed' virus, instead of weakened forms of strains of polio viruses like the ones used contemporarily by Albert Sabin, who was developing an oral vaccine. After successful tests on laboratory animals, on July 2, 1952, assisted by the staff at the D.T. Watson Home for Crippled Children, Salk injected 43 children with his killed-virus
Cold War tensions and the polio vaccine flew to Leningrad in June, 1956. As a result of a cooperation of Sabin and Chumakov in Leningrad, Sabin was able to test his attenuated vaccine when funding in America was declined. While Sabin was working behind the Iron Curtain, the Sabin-Chumakov vaccine was determined to be safe and effective. Cold War tensions caused Western scientists to refuse the reports from the Russians about the effectiveness of the Sabin vaccine. However, mass vaccinations of Sabin's vaccine spread throughout Eastern Europe from 1960–1963. Just as some Soviet virologists did not trust the Western Salk vaccine, Americans had similar reservations about the