[I couldn't believe my own eyes! (author's transl)].

The author reports his self observation of onchocerciasis contracted in february 1978 on the Sue River as he was launching a WHO Trypanosomiasis Control Project in the Southern Sudan. After a prepatent period of nearly three years, the first symptom to appear was the observation of a mobile microfilaria moving in the field of vision of the patient's right eye. This unusual clinical warning led to a routine diagnosis and treatment with diethylcarbamazine. The author then offers three comments on his case story: 1. Patients should be listened to, even if their complains appear queer and unorthodox according to text books descriptions. 2. Many if not most of chronic tropical diseases present themselves with a protracted and symptomless incubation period. People living in rural areas, usually short of medical facilities, should not be blamed for a so called irresponsability for their late reporting to a doctor or a public health worker. 3. An ailing epidemiologist finds some sort of solace in knowing where, when and how he has been trapped.