Cold War tensions and the polio vaccine was the first polio vaccine to receive approval of the U.S. government, and was used until 1961 in America, when the Sabin vaccine was recommended to replace it. Albert Sabin, a virologist who publicly disagreed with Salk and his killed vaccine, worked on creating a vaccine with live, attenuated vaccines. Despite Cold War tensions, in January, 1956 Mikhail Chumakov, the director of Moscow's Polio Research Institute, his wife and colleague Marina Voroshilova, and Anatoli Smorodentsev, traveled to the U.S. in order to study the Salk vaccine and visited the laboratory of Albert Sabin. With the clearance of the FBI, Sabin
Jonas Salk ... who read everything he could lay his hands on," according to one of his fellow students. Students had to cram a four-year curriculum into just three years. As a result, most dropped out or flunked out, despite the school's motto "study, study, study." Of the students who graduated, however, most would have the grades to enroll in CCNY, noted for being a highly competitive college. Salk enrolled in CCNY from which he earned a Bachelor of Science degree in chemistry in 1934. Oshinsky writes that "for working-class immigrant families, City College represented the apex of public higher education. Getting