BCG vaccine 400 per 100,000 in that higher risk context). The age of the person and the frequency with which BCG is given has always varied from country to country. BCG is prepared from a strain of the attenuated (virulence-reduced) live bovine tuberculosis bacillus, "Mycobacterium bovis", that has lost its ability to cause disease in humans. Because the living bacilli evolve to make the best use of available nutrients, they become less well-adapted to human blood and can no longer induce disease when introduced into a human host. Still, they are similar enough to their wild ancestors to provide some degree of
Inoculation theory to back that idea up. There are also scholars on the other side who suggest that too much of a delay lessens the strengthening effect of inoculation. With this being said, it has been revealed that the effect of inoculation can still be significant weeks or even months after initial introduction or the treatment showing that it does produce somewhat long-lasting effects (Banas & Rains, 2010). Involvement is the final element of the inoculation process. Pfau, et al. (1997a) defined involvement as "the importance or salience of an attitude object for a receiver" and is “among the most important and