EXISTING CHEMOTHERAPY AND ITS LIMITATIONS

Chemotherapy of African trypanosomiasis currently centres on three key drugs: pentamidine for chemoprophylaxis; suramin for treatment of the early stages of the disease; and melarsaprol for treatment of late stages when trypanosomes are present in the CNS. No drug is in routine use to prevent transmission during blood transfusion. In contrast, there are no drugs registered for chemoprophylactic use in Chagas' disease, though two, nifurtimox and benznidazole, are marketed in some countries in Latin America for treatment of both acute and chronic cases. Gentian violet is, however, available to prevent transmission during blood transfusion. Limitations of efficacy and/or problems of toxicity impose severe limitations on the usefulness of all of these drugs.