151 



1914 



Leese (A. S.). Final Report for 12 months ending 31st March 1914. 

 British East Africa ; communicated by the Colonial Office. 



In January 1914, the author travelled south from Serenli, on the 

 Juba R., by " Soames road " to Mfudu and examined it with reference 

 to the prevalence of biting flies in the dry season, and the possibility 

 of working camels on it in teams, as in Australia, but on the 4th March 

 was called to military service wath the Marehan Expedition. 

 He describes the symptoms of trypanosomiasis in Jubaland 

 camels and says that with two exceptions he has noted only 

 one form of the disease, viz. that due to long flagellated 

 trypanosomes resembling both T. brucei and T. evansi. These appear 

 to be spread through the agency of both Ghssina and Tahanus. The 

 native idea is that the acute form is caused by tsetse and the chronic 

 by Tahanus, but the author points out that in India both chronic and 

 acute cases are found where no tsetse exist. In Jubaland the acute 

 form runs its course and terminates in death in a few weeks. The sub- 

 acute form lasts from two to four months, and in the chronic form the 

 majority die in the first or second year of the disease, but a few recover 

 after three years or more ; hard-w^orked transport camels generally die, 

 whilst many meat-camels recover. The animal continues to suffer 

 after apparent recovery from occasional slight febrile attacks, of which 

 the symptoms remain unnoticed, and it thus acts as a dangerous 

 reservoir of infection for other camels, probably for a further period 

 of 1| to 2 years, and sudden death may occur at any time. In these 

 chronic cases in the camel, the natives seldom suspect "fly" but give 

 the cause of death some fancy name such as " Kud " or " Shimbe," 

 which are meaningless terms indicating any disease occurring suddenly 

 and accompanied by symptoms of brain derangement or of paralysis. 

 The author says that although no experiments have been possible 

 in Jubaland, there is no doubt whatever that the disease is spread by 

 biting flies and that G. jyallidipes is probably the host in which the 

 trypanosome undergoes part of its life-history, though any species 

 of tsetse on the Juba River must be under suspicion. Tahanus spp. are 

 also involved, but evidence points to their role being mechanical or 

 direct and therefore possibly only dangerous in the presence of another 

 infected animal. The habit of this fly is to pass from one animal to 

 another and so inoculate a healthy camel from a diseased one, a process 

 which experiment in North Africa, India and the Malay States has 

 shown to be easy. He strongly advises that all transport officers 

 should learn to recognise the species of Tahanus, and states that the 

 larger species are more active and therefore more dangerous. He 

 thinks it probable that biting flies such as Haemafapota and Lyperosia 

 occasionally contribute to the spread of the disease. He suggests 

 as preventive measures that camels should not be taken to places 

 infested by either tsetse or Tahanus, and that careful examination of 

 remounts should be made to prevent a mixture of diseased with healthy 

 animals. 



In the dry season, G. pallidipes is confined to the vicinity of dense 

 bush near water ; in the rainy season and for some time after, it may 

 be found as far as half a mile away from water and in greater numbers. 

 In the hot season it is most active in the dayhght before 9 a.m. and 

 after 4 p.m. and occasionally bites after dark. Probably in the cooler 



(C77) Wt.86 57. 1,500. 10.14. B.&.F.Ltd. Gp.13 6. A 



