[Acute schistosomiasis or Katayama syndrome: apropos of 2 mini-epidemics].

Schistosomiasis, or bilharziasis, is often oligosymptomatic but there is also an acute form, the Katayama syndrome. Observation of two groups of travelers who swam in the same lake near Banfora in western Burkina Faso, separated by an interval of one year, illustrates the high infection rate of Schistosoma mansoni (100% of swimmers, of whom 82% were symptomatic and 55% presented with fever). The incubation period was 4 to 6 weeks after exposure. 10 of the 11 subjects had eosinophilia (> or = 500/mm3) and IFAT serology was positive in all tested subjects. More than one year after exposure, one traveler (untreated) presented with a neurological deficit due to acute schistosomal myelitis. The diagnosis of schistosomiasis in a patient requires a search for the disease among his fellow travelers, even if they are asymptomatic.