A dot enzyme-linked immunosorbent assay (dot-ELISA) was developed using excretory-secretory (ES) antigens of Fasciola gigantica adult worms and freeze-thaw antigen (AFT) of adult Schistosoma mansoni worms. Specific IgG and IgM antibodies were simultaneously investigated in sera from 17 febrile eosinophilic hospitalized patients and 20 healthy controls. Dot-ELISA was shown useful and could differentiate fascioliasis from schistosomiasis prior to parasite egg detection in patient's stool. This assay is field and laboratory applicable.