Polio vaccine attenuated vaccine strains. In 1958, the National Institutes of Health created a special committee on live polio vaccines. The various vaccines were carefully evaluated for their ability to induce immunity to polio, while retaining a low incidence of neuropathogenicity in monkeys. Large-scale clinical trials performed in the Soviet Union in late 1950s to early 1960s by Mikhail Chumakov and his colleagues demonstrated safety and high efficacy of the vaccine. Based on these results, the Sabin strains were chosen for worldwide distribution. Fifty-seven nucleotide substitutions distinguish the attenuated Sabin 1 strain from its virulent parent (the Mahoney serotype), two nucleotide substitutions
Chris Sabin Chris Sabin Joshua Harter (born February 4, 1982) better known by his ring name Chris Sabin, is an American professional wrestler. He is best known for his work in Total Nonstop Action Wrestling (TNA) and currently works most notably for Ring of Honor (ROH). After being trained by Scott D'Amore, Sabin debuted in 2000 for Border City Wrestling, and quickly began competing for numerous other independent promotions. In 2003, Sabin joined TNA, and quickly won the TNA X Division Championship, which he later unified with the WWA International Cruiserweight Championship. In 2004, he also wrestled for Ring of Honor. In