An investigation of Borrelia burgdorferi in South Africa

Abstract

Four commonly occurring genera of ticks in South Africa were tested for their capacity to acquire and transmit Borrelia burgdoiferi, the causative agent of Lyme disease. Attempts were made to infect rabbits with a culture of B. burgdoiferi, and tick transmission experiments were carried out using the rabbits as the host of infection. Only one rabbit was successfully infected. Histological changes associated with a B. burgdoiferi infection were noted in this rabbit, but no spirochaetes were isolated. All other host animals failed to become infected with the B. burgdoiferi. As a consequence transmission experiments with the local ticks failed. Serological surveys conducted on rodents, horses and cattle using immunofluorescent and haemagglutination tests indicated that there is evidence that Borrelia species occur widely and that there is a possibility of B. burgdoiferi occurring in South Africa. Studies conducted on ticks from suspected endemic areas revealed the presence, in Ixodes bakeri only, of a spirochaete-like organism that reacted with monoclonal antibody H5332. Shortcomings of the study are highlighted and proposals are presented to address the problem of identifying specific B. burgdoiferi infections.