Abstract
Serological diagnosis of schistosomiasis using micro-ELISA was performed for 82 Japanese who were staying in Zambia for more than6 months, and 12 cases were found positive of infection, For these 12 cases, further laboratory examination and inquiries into the clinical course were conducted as well as investigation on possible source of infection. Of the 12 cases, schistosome eggs were identified in two )one with Schistosoma mansoni and the other with Schistosoma haematobium). The results of the laboratory examinations revealed eosinophilia in all cases and an increase of serum total IgE in eight cases. Fever was recognized in nine cases. Lumbago and hematuria which were suspected to have appeared accompanied by infection with schistosome was found in one case. Lake Kariba, a man-made lake created by the construction of a dam, was suspected to be the source of infection because all 12 sero-positive had a history of swimming in the lake. Among sero-negative, only two reported swimming in Lake Kariba.
Schistosomiasis is one of the important disease for prophylaxis while staying in an endemic area. Extreme care must be taken on exposure to water of man-made lakes because they are often turned into new foci of infection within relatively a short period.

Key words:
Schistosomiasis; man-made lake; micro-ELISA; Zambia; fever of unknown origin.