| Popis: |
M,{ANY methods of prophylactic immunization against tuberculosis have been recommended and attempted by such men as Koch, Pasteur, Baldwin, Theobald Smith, Trudeau, Pearson and Gilliland, Von Behring and others. During the past few years considerable publicity has been given the BCG vaccine of Calmette and some difference of opinion has been reflected in the literature regarding the efficacy of this vaccine, and especially regarding the danger that may be connected with its use in infants. The Bacillus Calmette-Guerin, which is the so-called BCG, was isolated from a heifer in 1908 by Calmette and his associates. They determined it to be the bovine type of tubercle bacillus and to possess moderate virulence for guinea pigs, rabbits and cattle. Continuous cultivation over a period of years on glycerinated ox-bile potato medium reduced the virulence of the organism so that it will now produce only small localized tubercles which heal within a few months. They further state that it is able to produce skin hypersensitiveness and immunity against infection with virulent tubercle bacilli. Calmette first recommended that new-born infants be fed the BCG, and it was so administered in 1921 at the Maternity Hospital in Paris. Since that time nearly 100,000 infants have been given this prophylactic vaccination, but only a relatively small number of these have been recorded in statistical studies, and the reports of Calmette have been attacked as being statistically incorrect. Calmette is convinced of the innocuousness of the vaccine and of its ability to immunize against tuberculosis, and many workers have found the bacillus to be non-virulent for small laboratory animals. Others have been able to |
