Antimycobacterial activity of indigenous South African plants.

South Africa has a heavy burden of tuberculosis (TB); an incidence of 526 cases per 100 000 of the population makes it one of the highest in the world. Along with other severely affected countries in eastern and southern Africa, there is a significant degree of coinfection with HIV and Mycobacterium tuberculosis (MTB). In the World Health Organisation (WHO) African Region, 31% of adults aged 15 49 years with TB are also HIV-positive. In South Africa, the cure rate for new smearpositive cases is 54%, and 63% of patients successfully complete their treatment regimen; these figures are well below WHO targets. They should be viewed within the context of rising caseloads and a projected fall in public sector health care investment, after a period of substantial growth from 1993 to 1998. Although the incidence of multiple-drug-resistant TB in South Africa is currently low, HIV has been associated with epidemic outbreaks of multidrug-resistant strains. There is an emerging view that the efficacy of TB control programmes, particularly with regard to adherence, could be increased if patients' beliefs about their infection were taken into account. Traditional healers are widely consulted in rural areas of South Africa and have been successfully recruited as short-course DOTS (directly observed therapy short-course) programme supervisors. There may be other aspects of traditional medicine that could supplement conventional treatments and impact on adherence and cure rates. For example, Honeybush tea, an infusion of leaves and stems of Cyclopia intermedia, indigenous to South Africa and rich in flavonoids, has been used for restorative purposes, such as soothing coughs and alleviating bronchial complaints including TB, pneumonia and catarrh. We have been investigating another herbal concoction with a long history of use in South African native medicine. Extracts of the roots of two species of indigenous geraniums, Pelargonium sidoides and P. reniforme, known locally as umckaloabo, were introduced into Europe as a ‘vegetable germicide’ and are still widely available, particularly in Germany, where they are used as over-the-counter preparations for treatment of various respiratory ailments.