The authors relate their experience of integrating screening for African human trypanosomiasis (AHT) caused by T.b. gambiense in a network of multi-purpose health centres at Nioki, Zaire. Since 1983 the health centre nurses have been trained in the laboratory techniques for AHT screening and have been given the essential equipment (microscope, slides, coverslips). The strategy used was that of passive screening of patients who came of their own accord to the health centre: systematic palpation and aspiration of lymph nodes, and examination of wet and/or thick blood films from patients with AHT-like symptoms (fever not responding to antimalarials, headache for over a week, somnolence, arthralgias, pruritus, weight loss). When a trypanosome was detected, the patient was referred to the hospital for confirmation and lumbar puncture. From 1983 to 1987 the proportion of new cases detected by the health centres rose from 0% to 31.1%, while the returns of the mobile teams diminished as the disease regressed. Nevertheless, only 22.1% of the new cases detected by the health centres had normal CSF, as opposed to 64.8% of the new cases detected actively by the mobile teams. These two approaches therefore seem to be complementary: 83% of the new cases detected by the health centres were diagnosed on lymph node aspirates and/or wet films, and it is likely that better use of thick blood films could improve the performance of the health centres.(ABSTRACT TRUNCATED AT 250 WORDS)