BCG vaccine bacilli that seemed less virulent, and changed the course of their research to see if repeated subculturing would produce a strain that was attenuated enough to be considered for use as a vaccine. The BCG strain was isolated after subculturing 239 times during 13 years from virulent strain on glycerine potato medium. The research continued throughout World War I until 1919, when the now avirulent bacilli were unable to cause tuberculosis disease in research animals. Calmette and Guerin transferred to the Paris Pasteur Institute in 1919. The BCG vaccine was first used in humans in 1921. Public acceptance was slow,
Inoculation theory Inoculation in this area improves peoples resistance to such attacks, examples and directions for future work are provided. Recent studies have approached inoculation by incorporating psychological reactance theory (Brehm, 1966, 1972; Brehm & Brehm, 1981) as a means to enhance resistance outcomes through inoculation theory's two key components: threat and refutational preemption. Miller, et al. (2013) focused their study on emerging adults and their reactance to persuasive appeals. Research has demonstrated that this population is in a transitional stage in life (Voyer et al., 2005) and are more likely to defend their behavioral freedoms if they feel others are attempting