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 needle slant culture to needle, the open end of the culture will be treated with flame and the cap will be replaced. An inoculation needle is used in the transfer of microbial organisms from plate culture to needle by first sterilizing the needle to prevent contaminants. The lid of the agar plate culture is then removed to allow the needle access to the microorganisms cultured on the agar plate. The lid is held hovering above the culture plate to prevent contamination from the surrounding environment. The inoculation needle after incineration is cooled down on an uninoculated region of the agar plate