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
Texans for Vaccine Choice Texans for Vaccine Choice Texans for Vaccine Choice (TFVC) is a political action committee in Texas which advocates for exemptions to vaccination requirements. TFVC has been criticized as anti-vaccine by David Gorski and some news outlets. Texans for Vaccine Choice was founded in 2015 by a group of mothers, lead by Jackie Schlegel, who opposed legislation proposed by state representative Jason Villalba (R-Dallas) which would have eliminated conscientious exemptions to vaccination requirements in the state of Texas. Referring to this bill, TFVC executive director Jackie Schlegel said “This is Texas. We believe in parental rights in Texas. Like, that is