L30 THE ACUTE SELF-LIMITED INFECTIONS 



The antiserum may also be used as a preventive, given sub- 

 cutaneously in generous doses, particularly in times of epi- 

 demic. Our knowledge is incomplete as to its full value, but 

 the reports so far are promising. Vaccines of dead dysentery 

 bacilli have been found to produce a fairly high grade of 

 immunity but give such sharp reactions, for the reason given 

 above, that their use has not become general. In times of 

 epidemic their use might be indicated but the disease can be 

 combated by general hygienic measures. 



VINCENT'S ANGINA. 



Vincent's angina is a very important inflammatory disease 

 of the tonsils and pharynx, sometimes simulating diphtheria 

 in that a false membrane is also characteristic of the disease. 

 The causative bacteria are spirilla and fusiform rods, prob- 



Fio. 40. Vincent's bacillus with accompanying spirochetse. (Park.) 



ably two stages of development of the same organism, since 

 it is believed that the former develop from the latter. The 

 early stage is the time when the pseudomembrane appears, 

 but this soon gives place to punched-out ulcerations. The 



