38o 



SPECIFIC MICRO-ORGANISMS 



Syphilis is an inoculation -disease which has been widely 

 prevalent throughout the civilized world since the early part of 

 the i6th century. Transmission takes place by direct contact and 

 in the great majority of instances by venereal contact, although 



Fig. 152. — Spirochala pallida stained by Levaditi method. The section shows 

 an infarcted lymph vessel at the junction of two branches. The lumen is filled with 

 leukocytes. The spirochetes follow the lymph vessel for the most part, but are also 

 penetrating into the surrounding tissue. (From Dofiein after Ehrmann.) 



many authentic cases of transmission by means of intermediate 

 objects are known. The spirochete is able to live for some hours 

 outside the body if drying is prevented. The primary lesion 

 develops at the point of inoculation about two weeks after that 

 event, first as a papule, which becomes vesicular and. ulcerates, 



