VACCINES AND SERA 273 



culosis. But even among cattle the method is not yet suited 

 for practical application. 



In man there exists an auto-vaccination, since practically all 

 adults have been slightly affected by this disease, and only a 

 small fraction succumb. Both in medical and surgical practice 

 it is common to find tuberculosis of the skin, of the joints, and 

 of the bones healing up and even apparently protecting the 

 patients against contracting pulmonary phthisis. It is on these 

 lines that is to be sought a method of vaccination against 

 tuberculosis. Up to now none exists. 



Bacteriotherapy. 



Vaccines and sera are not the only remedies furnished to 

 medicine by bacteriology. Bacteriotherapy consists in modify- 

 ing a given flora by adding to it other bacteria which are 

 antagonistic or favourable to certain microbial species. In 

 discussing the intestinal flora we have indicated the principles 

 of the bacteriotherapy of intestinal infections. In the future 

 this will be developed, and health-giving bacteria will form 

 part of our diets. 



Bacteriotherapy has also been attempted in the case of 

 cancer and lupus, where injections of streptococci have been 

 given, and in the case of chronic boils, where injections of 

 yeast have been tried. These attempts are still semi-empirical, 

 but this is no reason for despising them. 



The lactic bacilli have not been utilized in intestinal bacterio- 

 therapy only. Surgery has employed them to combat puer- 

 peral infections, injuries occurring during labour, inflammations 

 of the cervix, and even peritonitis. They evidently act by 

 modifying the " soil." It is obvious that they find their chief 

 success in combating infections of closed cavities, such as we 

 have in rhinitis, sinusitis, ethmoiditis, and otitis. 



Bacteriotherapy in the mouth is not less rational than in 

 the intestine. The lactic flora has succeeded in curing 

 chronic inflammations of the gums and obstinate pyorrhsea 

 alveolaris. All the infectious diseases which enter by the 



