It was prepared for the first time at the Pasteur Institute in Paris in 1906 by Albert Calmette and Camille Guerin. In France the BCG vaccine has been in wide use in humans since 1921. The vaccine proved to be the safest and the most widely used vaccine.
It has an efficacy of between 50 and 80 percent, depending on the natural occurrence of other forms of mycobacteria other than mycobacterium tuberculosis in the environment in which a person lives in.
It is not currently recommended in developed countries as routine childhood vaccination because the incidence of tuberculosis tends to be much lower there.
Having had a previous BCG vaccination will affect a Mantoux test result.
The BCG vaccination should be given intradermally by a nurse skilled in the technique.