Some clinical observations on trypanosomiasis rhodesiensis

Abstract

1. The object of the paper is to record some clinical observations made during the study of 94 consecutive cases of Rhodesian Sleeping Sickness.2. The main factor in the epidemic spread was man-fly-man transmission. The occurrence of human cases with no history of contact and the high T.bracei infection rate among the local fauna are recorded, as the possibility of there being some reservoir cannot be excluded.3. The incubation period is probably between 1-3 weeks.4. The average duration of the illness is five months.5. There was an acute febrile onset in 24/£ of cases. Variations in the subsequent course are found and it is considered that these are due to the existence of strains of trypanosoines of different virulence.6. The central nervous system may be involved at a very early stage. This results in grave pathological changes, but the virulence of the infection is such that symptoms arising from its effect on the heart and other viscera predominate over those due to central nervous system involvement until the last few weeks of the illness. Cardiac symptoms are important and the essential lesion is a toxic myocarditis.7. The axillary group of glands are those most constantly enlarged.8. It is in cases which have relapsed after treatment that mental symptoms are most pronounced. In relapse a new strain of trynanosames has been created, of lowered virulence but resistant to the action of drugs.9. 'Bayer 205' has a strong and immediate effect oh infections of the peripheral blood but its action is not always permanent and it cannot penetrate into the deeper tissues. Tryparsamide is slower in action but it maintains a sterilization made by 'Bayer' and it can exert a beneficial action on the central nervous system.10. Treatment by * Bayer* should he followed immediately by Tryparasmide • A routine treatment by this method gives satisfactory results if treatment is started early in the course of the illness, hut even the most intensive and prolonged doses of the two drugs in combination cannot he relied upon to effect a cure if the disease is well established.