SPIROCHETE 387 



SPIROGHETE. 



The first spirochete described under the name of Spirocheta 

 plicatilis by Ehrenberg and found in marshy water probably does 

 not belong to the organisms classified today as spirilla, or spirochete. 

 The most important pathogenic species are the following : Spirocheta 

 Obermeieri, found in relapsing fever in man ; Spirocheta Duttoni, found 

 in African tick fever in man, and Spirocheta pallida, found in syphilis 

 in man. There are also spirochete causing diseases of domestic birds 

 and others, which have been found in mammals other than man, but 

 which are probably not very pathogenic. 



Spirochete in Man. SPIROCHETA OBERMEIERI. The first patho- 

 genic spirillum was discovered by Obermeier in 1868 in the blood of 

 persons suffering from relapsing fever. Though the role of bacteria 

 in the production of infectious diseases was not yet well recognized 

 at this early time, it was, nevertheless, believed that this organism was 

 the cause of the disease. All spirochete known at present have 

 resisted every attempt at artificial cultivation, and they are not as well 

 known as most other pathogenic bacteria. It is now generally believed 

 that the Spirillum Obermeieri is transmitted from sick to healthy 

 persons through the bites of bedbugs. According to Novy and 

 Knapp the spirochete of European and Indian relapsing fever are not 

 identical, but different species. 



SPIROCHETA DUTTONI. Tick fever, a disease of man prevalent in 

 Equatorial Africa, was shown to be an infection due to spirochete. 

 The first observations concerning its nature were made by Ross and 

 Milne in Uganda and by Button and Todd in Eastern Congo. This 

 disease is transmitted through the tick Ornithodoros moubata. Robert 

 Koch, who studied the disease in German East Africa, demonstrated 

 the presence of spirochete in the eggs as well as in the adult ticks. 

 Novy has shown that the spirochete of African tick fever is a species 

 distinct from the organism of European and Indian relapsing fever, 

 and he has proposed the name of Spirocheta Duttoni in honor of 

 Dutton, who lost his life while studying the disease in Africa. 



SPIROCHETA PALLIDA. The interest in the study of spirochete 

 was enormously increased and undertaken by hundreds of investi- 

 gators when Schaudin and Hoffmann reported that they had found an 

 exceedingly fine, slender, long, and very typical spirocheta in the 

 primary and secondary lesions of human syphilis. It was first named 

 Spirocheta pallida, later Spironema pallida, and still later Treponema 

 pallidum, but it is now most commonly known in literature as 

 Spirocheta pallida, or the spirocheta of syphilis. 



Spirocheta pallida is found in almost every primary syphilitic 

 lesion; often in secondary but very rarely in tertiary lesions. It is 

 a very slender spiral, from 4 to 14 micra long. It can best be seen in 

 a living state, and unstained by the aid of the dark field illuminator. 



