136 THE ACUTE SELF-LIMITED INFECTIONS 



precisely as has been described for typhoid fever. This 

 " vaccine" prophylactic, and one of the first of such pro- 

 cedures, gives an immunity for a few months. Immu- 

 nity against a subsequent attack always follows plague. 

 Thus there is an active immunizing therapy for plague, 

 and passive immunizing substances can be added to 

 the patient's own defenses. 



SPIRILLUM CHOLERA ASIATICS. 



Cholera is an acute inflammatory disease of the small 

 intestines characterized by profuse watery stools, a 

 profound prostration, muscular pains, and high fever. 

 It is caused by the Spirillum cholerce asiatic or 

 cholera spirillum or vibrio. The bacteria enter the 

 body only through the mouth, and settle upon the 

 mucous membrane of the lower part of the small 

 intestine. This they penetrate only as far as the 

 deeper layers of the innermost coat of the tube, and 

 by their growth cause a shedding of the lining. The 

 shreds of the desquamated mucous membrane pass off 

 with the watery discharges, and cause the characteristic 

 "rice-water" stools. The bared and congested surface 

 permits absorption of the poisons of the spirillum, the 

 body of which does not itself enter the blood stream. 

 The poison quite frequently has a depressing action 

 upon the heart muscle. It is not quite certain whether 

 or not this is a wholly extracellular toxin or combined 

 closely with the bacterial bodies. It is probably mostly 

 of the latter character, an endotoxin separated upon 

 the disintegration of the germ cells. 



Cholera is a disease transmitted almost exclusively 



