Onyalai at Rundu, Namibia 1981–1988: age, sex, morbidity, mortality and seasonal variation of 612 hospitalized patients

Of 51 263 admissions to Rundu State Hospital in Namibia between 1981 and 1988, 612 (1·19%) were diagnosed as onyalai. The annual incidence varied between 0·96% and 1·66% of all admissions. The female to male ratio was 3:2. The mean age at presentation was 24·8 years (range 6 months to 80 years) and the mean hospital stay (and duration of clinical bleeding) for the years 1981 to 1982 and 1985 to 1988 was 7·68 d (range 1–38 d). Although the highest number of cases occurred during the months March, April and May a statistically significant monthly variation was not found. The treatment policy of commencing intravenous fluid on admission and a blood transfusion whenever the haemoglobin dropped below 10 g/dl in patients with active bleeding was associated with a mortality rate of 2·78% compared to 9·8% in cases recorded up to 1981.