7. EAST COAST FEVER— " A HISTORICAL REVIEW." 

 By C. E. Gray, M.R.C.V.S. 



It is now ovei- ten years since tliis ilisease became the subject of 

 scientific inquiry at the hands of Prof. Koch, who lirst observed it at 

 Dar-es-Salaam in 1897, whei-e he was led by the result of experiments 

 which he made at that time to regai-d it as identical with tlie Texas 

 fever or red water described so ably by the well-known American in- 

 vestigatois Smith and Kilbourne, although in his report, published at 

 that time, he dwelt at some length on certain differences between the 

 •microscopic appearances presented by the blood of certain cases exa- 

 mined by him and those recorded by the American observers. To quote 

 Koch's own words, he says : " In a certain number of the animals 

 <?xamined by me I could trace the developed Fyro^oma biyemiun.oi 

 (the specific organism of Texas fever). It answered the description 

 given of it by Smith and Kilbourne so perfectly that no room for 

 ■doubt was left i-egarding the identity of the parasite here found with 

 that discovered in American cattle. Only with regard to the earlier 

 forms of the Pyrosoma and the relations of both it and the full-grown 

 parasite to mild and severe Texas fever, I have come to difierent con- 

 clusions from the American investigators. 1 found, namely, pai-ticu- 

 larly in the red blood corpuscles of cases which took a severe f«)rm and 

 rapidly proved fatal, strange forms resembling )niniature staves, so 

 that one might take them to be bacilli. Tliese ait' frecpiently slightly 

 curved, and sometimes so strong that they foi'm rings, and in that case 

 look veiy much like the parasite of tropical malaria. Fretjuently these 

 little staves are slightly thicker in the centre ; they then clearly show 

 a double outline and assume the form of a willow leaf. Between such 

 foi-ms and the pear-shaped form of the full-grown Pyrosoma there are 

 a number of intermediate stages, and I have in consequence formed 

 the conviction that the parasites I found are the real first forni'^ of tlie 

 Pyrosoma." 



This abnormality in the microscopical appearances of the blood of 

 these rapidl}' fatal ciises, however, ajipeais U) be tlie only point of 

 difference then noted by Prof. Koch, as he makes no reference what- 

 <'ver to the peculiar post mortem lesions whose existence was afterwai'ds 

 recorded in Rhodesia. In the report already quoted, Dr. Koch maps 

 out the extent of the infected area from information obtained locally, 

 giving it as his opinion that the disease is a coastal one which has long- 

 been endemic on the African coast and the island of Mafia, probably 

 extending southwards into the English colonies. In discussing the 

 width of the infected belt, he says, " A few miles from the coast one 

 hears of no more cattle pests that would point to the presence of Texas 

 fever. The reason for this lies simply in the fact that from the coast 

 towards the interioi- a strip of land is found, numy days' journey in 

 breadth, where next to no cattle breeding is done. The tril)es living 



