312 EASTERN ETHIOPIA xxv 



iilways attributed to the bite of a tick wliicli infested 

 old camping-grounds along the caravan routes. No 

 positive proof was forthcoming that the fever attributed 

 to the bites of ticks was really caused by them until 

 P. H. Ross and A. D. Milne, working in Uganda, demon- 

 strated the presence of a spirochc«ta in the blood of 

 patients who attributed their illness to the bite of a 

 tick. 



It appears that a tick which has fed on a person 

 suftering from tick fever may convey the parasite to 

 healthy persons by biting them. Also the larva 

 hatched from the eggs laid by an infected tick can 

 convey the disease, as well as transmit it to the 

 second generation, and the nymphs are infective to mice 

 and monkeys. 



Tick fever appears to run a different course in 

 natives and in Europeans. In the native, the chief 

 symptoms are fever, headache, pains in the trunk and 

 limbs, and vomiting. There may be diarrhiea and 

 cough. The temperature remains high for two days, 

 then falls by a crisis, and, as a rule, the patient recovers, 

 relapses being unusual. 



In Europeans the disease begins in much the same 

 way, but the symptoms are more severe and last longer. 

 After the crisis the patient appears apparently well ; he 

 will get a relapse after a few days, or even three weeks, 

 and still be liable to a series of relapses, usually five or 

 six, but sometimes as many as a dozen. The main 

 features of the recurrent attacks are those of the 

 primary onset of the disease, fever, pain, and vomit- 

 ing : these relapses may occur in temperate climates 

 long after the patient has left the country where he 

 was infected. The disease is rarely fatal in man. 



There are two important diseases which aifect 

 domesticated animals in East Africa due to the bites 

 of ticks : namely Red-water and East Coast Fever. 



Red-water is a disease which affects cattle and is 

 named after its most conspicuous sign, red urine, the 



