RESUMO
The authors report results obtained after combination of a serological diagnostic test and the early treatment of suspected cases (a person with a positive serological test without parasitological confirmation) in an area in Zaire where sleeping sickness caused by Trypanosoma brucei gambiense is endemic. The serological test used was Testryp CATT, having a very high sensitivity and quite a high specificity, which is easy to handle in the field and which permits results to be obtained on the spot. The treatment employed was a medication active in the first stage of the disease (hematolymphatic stage), safe to handle, with few side effects and easy to administer (diminazine). This strategy was applied for one year in the area from Fankana-Kalakitini in the Bandundu region in Zaire. The entire population was examined with the classical methods, combined with the serological test Testryp CATT, and this every six months. People positive for the serological test (but negative for the parasite) received one injection of the proposed medication; but people in whom parasites were found got classic treatment. After this period, we were able to demonstrate a clear decline in the incidence rate of new cases (parasite positive), but also in seropositivity rates in the general population. The authors believe that in a circumscribed area where the disease is endemic, the combination of a serological test and early treatment of suspected cases can rapidly diminish the incidence of the disease to an acceptable level.