The authors determined the cause of myelopathies in 33 HIV seropositive individuals in KwaZulu/Natal, South Africa. The main associations were with human T-cell lymphotrophic virus-I, tuberculosis, herpes tester, and syphilis. A novel association with probable bilharziasis was noted. Only one case of vacuolar myelopathy was identified. Opportunistic infections will probably persist until routine antiretroviral therapy becomes widely available in South Africa.