Biological Aspects of Trypanosomiasis Research

Abstract

This chapter outlines the significant advances in the development of methods that of reducing the incidence of pathogenic trypanosomiasis in man and domestic animals. It proposes four approaches in this context: chemotherapy, reduction or eradication of the arthropodan vector, manipulation or removal of the vertebrate host, or methods involving immunology. Trypanosomes can readily be counted in the haemacytometer when their concentrations exceed about antilog 4 per ml; in fluids such as blood, which require dilution before counting, the threshold is correspondingly higher. Even fulminant parasitaemias rarely exceed antilog 8.5 trypanosomes per ml, so that counting by visual methods is largely confined to the upper range of trypanosome concentrations. Infectivity measurement offers a tool for the quantitative study of the prime feature of trypanosomes, their potentiality to establish themselves and multiply in particular situations. Electron microscopy has provided remarkable advances in knowledge of the morphology of trypanosomes, mainly relating to the Trypanosoma brucei subgroup. Systematic study of the factors determining the establishment and potentiality of trypanosomes in culture would be advantageous.