58 



died, the remainder were removed to Umtali, Rhodesia, where they con- 

 tinued to die. It appears that the cause of death at Beira was red water 

 (Texas fever), and that the lot which were removed to Rhodesia developed 

 the usual symptoms of the East African disease as a result of being grazed 

 on ground infected by cattle introduced from German East Africa ; the 

 disease now attracted more attention, although still associated with 

 redwater (Texas fever) by the first workers. East Coast fever was sub- 

 sequently introduced into the Transvaal in May, 1902, apparently from 

 Lourenco Marques via the Delagoa Bay Railway, and first appeared at 

 Komatipoort and Nelspruit, and thence eventually spread to other 

 districts and Swaziland. After its introduction into Rhodesia and the 

 Transvaal, and when its study was systematically undertaken, it was 

 found not to be identical with redwater (Texas fever), but to be a disease 

 of its own. 



In the experiments with ordinary redwater inoculations it was noticed 

 that the blood of animals which were injected with blood of redwater 

 immune animals, showed on microscopical examination the typical 

 Babesia higemina. When, however, the examination of the blood was 

 continued endoglobular parasites similar to those of Thieleria parva were 

 also observed. This phenomenon led some observers to conclude that 

 these organisms are a stage in the life-cycle of Babesia bigemina. Others, 

 however, held that the small endoglobular organisms found in the blood 

 of animals had to be connected with East Coast fever. At the Veterinary 

 Conference held in Bloemfontein in 1903,* Professor Koch stated that 

 he had found the parasites of East Coast fever in smears of blood collected 

 from East London cattle, and concluded that that disease existed on 

 the south-eastern coast of Africa, basing his opinion on the presence of 

 the bacillary piroplasms. Theiler, who had carried out some investiga- 

 tions in connection with the appearance of small endoglobular parasites, 

 before East Coast fever was known to the Transvaal, in cattle out of 

 countries known to be free from that disease, considered the piroplasm 

 referred to by Koch was probably a species of its own and not connected 

 with East Coast fever. In the light of our present knowledge it is 

 evident that the parasites observed by Koch were those which were 

 formerly associated with the immune redwater ox, but which are now 

 known to be a distinct species, viz., Babesia mutans. Since Babesia mutans 

 exists in the Transvaal wherever redwater is found, and it is the exception 

 to find the one unassociated with the other (this association of Babesia 

 bigeminum and Babesia mutans appears to exist in other countries, e.g. 

 China, Japan, Annam, Madras), and since it is known that Madagascar 

 cattle are irmnune to both redwater (Texas fever) and mutans, its 

 introduction may be traced back to the importation of cattle from that 

 country. 



* Eeport (if the Piuceediiigs of fhe C'oufei'ence on Diseases amongst Cattle and other Animals in 

 South Afi-ica; Bloemfontein, 1903. 



