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 are more likely to be inoculated by issue/advocacy messages. They use Mobil Oil's issue/advocacy campaign to test the hypotheses. The first hypothesis was supported by the data. There was a significant effect provided by inoculation. Additionally, H1 showed that issue/advocacy inoculation messages and attack messages vary in effectiveness depending on the content. The result was also noted in the results of H2, which were also supported by the results. Finally, the results indicated that political views play a role in the effectiveness of the campaigns. Thus, confirming H3, that conservatives are easier to inoculate. They also posed a research question