BCG vaccine extensively used even in countries where efficacy against pulmonary tuberculosis is negligible. A number of possible reasons for the variable efficacy of BCG in different countries have been proposed. None have been proven, some have been disproved, and none can explain the lack of efficacy in both low-TB burden countries (US) and high-TB burden countries (India). The reasons for variable efficacy have been discussed at length in a WHO document on BCG. BCG has protective effects against some non-tuberculosis mycobacteria. BCG has been one of the most successful immunotherapies. BCG vaccine has been the "standard of care for patients with
Inoculation theory (Banas & Rains, 2010, p. 285). Recent research has studied the presence and function of word-of-mouth communication, or post-inoculation talk (see Compton & Pfau, 2009), following exposure to inoculation messages (e.g., Ivanov et al., 2015). Delay is the next element that is necessary in the inoculation process. There has been much debate on whether there is a certain amount of time necessary between inoculation and further attacks on a persons' attitude that will be most effective in strengthening that person's attitude. McGuire (1961) suggested that delay was necessary strengthening a person's attitude and since then many scholars have found evidence