274 "SPECIFIC TREATMENT" OF DISEASE 



in small doses. He discovered a compound called 

 Atoxyl, which exerted a marked effect on the para- 

 sites of sleeping sickness and which has been largely 

 used in practice. There are drawbacks and dangers 

 to its use, a drawback being that the trypanosomes 

 become arsenic-resistant and other remedies such 

 as tartar emetic have to be subsequently used to 

 alleviate the patient. There is no doubt that these 

 drugs prolong the life of persons suffering from 

 sleeping sickness in its early stages and that they 

 may help the body to throw off the infection. 

 Unfortunately trypanosomiasis may last for years, 

 and cases have been observed where apparently 

 cured persons have suffered from a fatal return of 

 the disease a year or two after they were treated. 

 It is clear, therefore, that the ideal remedy still 

 requires to be found. The results obtained are, 

 however, full of promise for the future. In the 

 meantime efforts have been made to lessen the 

 chances of man's becoming infected by attacking 

 the haunts of the tse-tse flies which convey the 

 disease; the excellent results obtained in combat- 

 ting the mosquitoes which convey malaria and 

 yellow fever and the ticks which convey piroplas- 

 mosis having aroused hopes that similar measures 

 directed against tse-tse flies might yield good results. 

 The most striking results obtained have been 

 those in the diagnosis and treatment of syphilis, 

 and we may consider the steps which have led to 

 these discoveries. Although syphilis has been known 



