EVALUATION OF ALKALINE-PHOSPHATASE IMMUNOASSAY AND COMPARISON WITH OTHER DIAGNOSTIC METHODS IN AREAS OF LOW TRANSMISSION OF SCHISTOSOMIASIS

The alkaline phosphatase immunoassay (APIA) is an antibody detection t echnique which permits the diagnosis of schistosomiasis using a butano lic extract preparation from adult worms. APIA has demonstrated high s ensitivity and specificity in previous reports with well characterized human sera. Its potential as a diagnostic tool for epidemiological su rveillance was assessed in comparison with three other diagnostic test s: stool examination, ELISA with soluble egg antigen (SEA) and the cir cumoval precipitin test (COPT). APIA was 100% specific in an area with out Schistosoma mansoni transmission and had 89% sensitivity in an end emic area where 69% of the infected subjects excreted less than 100 eg gs/g of faeces. It was found to be less sensitive in children under 5 years of age who were positive by the COPT test. APIA can be applied a s an initial screening test, based on its high sensitivity, specificit y, absence of cross-reactivity with intestinal parasites and the fact that it is a technique suitable for use in epidemiological surveillanc e. (C) 1997 Elsevier Science B.V.