Relapsing Fever in Africa

Abstract

The relapsing fevers, broadly classified into the louse-borne and tick-borne varieties, are characterised clinically by an initial pyrexia of 2-4 days’ duration, followed at intervals of a few days by successive relapses, and caused by spirochaetes (Horrelia) which are present in the circulating blood in the acute stages of the illness. Classification and nomenclature are not yet well-defined in the spirochaetes which are morphologically indistinguishable but biologically separable. The spirochaete is specifically referred to as Borrelia recurrentis (or B. obcr- meiri) in the louse-borne form. In the tick- borne form a variety of names has been given to the responsible spirochaetes, largely indicating the geographical region of occurrence or the worker who identified them, thus, Borrelia duttoni is the spirochaete of Central and Southern Africa, and B. venezuele.nsis, B. aegyptica, B. berbera, B. kochii, B. tiovyi. are names of the spirochaetes found elsewhere.