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 needle the aseptic technique. An open flame from an incinerator, a bunsen burner, or an alcohol burner is used to flame along the tip and the length of the needle that is to be in contact with the inoculum. For ease of manipulation it is common practice to hold the needle with the dominant hand as if handling a pencil. The needle will be flamed at a downward angle through the flame’s inner cone until it is red-hot. The downward angle will minimize the amount of microbial aerosols created. Inoculation needles must be sterilized prior and following contact with microbial life