OTHER SPIROCH^TES 73 



Yquitos, are conspicuous examples of tropical cities which have 

 been cleared of the disease which once made them highly dangerous 

 to visitors and a menace to the rest of the world. In connection 

 with an incessant war on the transmitting mosquito in all stages 

 of its life history, all known or suspected cases of yellow fever 

 should be carefully screened so that mosquitoes can have no access 

 to them. 



Rat-bite Fever 



In many parts of the world, especially in Japan, there occurs a 

 disease which follows a rat bite, and is therefore known as " rat- 

 bite fever." It has been reported from various localities in the 

 United States. Some inflammation occurs at the place of the 

 bite and the neighboring lymph glands swell up. After several 

 weeks a high fever ensues, preceded by chills and headache. 

 The apparently healed rat bites become inflamed and there is 

 usually a red rash which spreads all over the body. In from three 

 to seven days the fever subsides but it recurs, usually within 

 a week, with similar symptoms, and the rash is more constantly 

 present than in the first attack. In some cases there are still 

 more relapses. 



The similarity of the disease to such spirochaete diseases as the 

 relapsing fevers is obvious, and its spirochaete nature was long 

 suspected by Japanese physicians, especially when they found 

 salvarsan to be effective in its treatment. Within the past 

 few years some Japanese physicians (Futaki, Takaki, Taniguchi 

 and Osumi) discovered in seven out of eight patients numerous 

 actively moving spirochsetes in the broken-out skin and in swollen 

 lymph glands. Animals were successfully inoculated with the 

 disease by means of bits of skin tissue and blood containing spiro- 

 chsetes. The organism, which has been named Spirochceta morsus 

 muris, is described as being an actively moving animal, larger 

 than Sp. pallida of syphilis, but smaller than the relapsing fever 

 spirochsetes. It is rather short and thick with an attenuated 

 portion or flagellum at each end. Long spirochsetes, at first 

 thought to be specifically distinct from the short thick forms, 

 also are found in human infections. According to Kaneko and 

 Okuda these are probably degenerate forms resulting from the 

 action of antibodies. 



The Japanese investigators have been unable to find the spiro- 



