Serodiagnostic tests for West African Trypanosomiasis

Abstract

Early diagnosis of infection with Tryponosoma brucei gambiense is not easily achieved under the field conditions of West and Central Africa. Parasitaemia fluctuates daily and parasites may be difficult to detect even in thick blood films. Even miniature anion-exchange centrifugation techniques, which concentrate parasites from the blood to assist microscopic examination, are limited by the inconsistent parasitaemia which char~cterises infection with T. b. gombiense. In contrast the higher parasitaemia associated with the more virulent T. b. rhodesiense in East Africa makes parasitological diagnosis more straightforward. Recently, however, the development of new serodiagnostic tests for West African sleeping sickness by Belgian research workers and a profitable collaboration with industry, have produ:ed diagnostic kits which fulfil many of the rigorous requirements of field work. Modified versions of the indirect haemagglutination test of Bone and Charlier t, (now marketed as CELLEGNOST by Behringwerke and TESTRYP IHA by Smith Kline-RIT), and one of the cardagluttination testofMagnus etaL2,(now marketed as TESTRYP C A l F by Smith Kline RIT), have been evaluated in the field for the W H O in endemic areas endemic for T. b. gambiense sleeping sickness 3.4. Details of the development of two of these tests and