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 reassures viewers that their opinion is still right and that Macs are in fact better than PCs. The inoculation theory in these ads keep Mac users coming back for Apple products and may even have them coming back sooner for the bigger and better products that Apple is releasing. That last part is especially important in a field like technology because it is continually changing and something new is always being pushed out onto the shelves. An example of inoculation theory usage in politics are present in studies indicating that it is possible to inoculate political supporters of a candidate