4^8 SCIENCE IN AFRICA 



dependent on that of the tsetse flies which have been considered in 

 Chapter X. Research on the cure of the disease in Tanganyika 

 and Nigeria has advanced knowledge materially. The drugs used 

 have mostly been synthesized in Bayer laboratories, and extensive 

 trials have shown that the treatment of most cases of trypanoso- 

 miasis may be attempted with a fair hope of success. Prophylactic 

 injections of domestic animals against infection are not yet prac- 

 ticable, but a new compound 'Surfen C, not antimonial, has given 

 the most promising results. 



Attempts have been made in various parts of Africa to work out 

 some process of immunization of cattle and human beings. Pro- 

 gress towards this end has been made particularly by Professor 

 Claus Schilling, Director of the Robert Koch Institute in Berlin, 

 who has continued since the war to visit Tanganyika at intervals 

 for research, receiving facilities at Mpwapwa. Building on the 

 natural potentiality of young game animals and some breeds of 

 cattle to establish complete resistance as a result of repeated infec- 

 tion with trypanosomiasis, he has worked out a process in which 

 the young susceptible cattle are subjected to repeated and increas- 

 ing doses of trypanosomes. The process has been patented, but is 

 oflfered for use free to the German Government and to Tanganyika. 

 The results are summarized in English in two papers (Schilling 

 1934 and 1936b). 



In addition to the major diseases, considerable advances have 

 been made in the etiology of less important troubles such as malig- 

 nant catarrh, turning sickness, para-typhoid, measles in calves, 

 sweating sickness, sterility, contagious abortion, anthrax, and 

 bovine haematuria. 



A number of sheep diseases formerly acted as limiting factors to 

 sheep farming in East Africa, and research has been carried out 

 especially on Nairobi sheep disease (Daubney and Hudson 1931a, 

 1934)5 ^ift valley fever (Daubney and Hudson 1931b, 1933), 

 heartwater, parasitic worms (Daubney 1928, Hudson 1934), 

 respiratory diseases, streptothricosis and pulpy kidney. Horse- 

 sickness has likewise been investigated (Walker 1931). In pigs 

 considerable progress has been made with East African swine 

 fever and swine influenza, and in poultry fowl typhoid, Newcastle 

 disease, and roup occupy the foreground. 



