A SIMPLE TRYPANOSOMA-CRUZI ENZYME-LINKED IMMUNOASSAY FOR CONTROL OF HUMAN INFECTION IN NONENDEMIC AREAS

An enzyme linked immunosorbent assay (ELISA) was developed for detecti ng IgM and IgG antibodies against Trypanosoma cruzi in blood bank dono rs from endemic or nonendemic areas. A crude extract of trypomastigote s from cultures was used as antigen. A total of 494 serum samples from patients with acute, congenital, or chronic form of Chagas' disease, and from healthy French individuals were studied. The sensitivity of t he ELISA was determined with 89 serum samples from chagasic patients a nd was evaluated to 98.8%. The specificity was determined with 405 ser um samples from French blood transfusion centers donors and evaluated to 98.3%. Two hundred and eighty-five serum samples from blood donors from Argentina and Brazil were also tested. Furthermore, in order to a ssess the absence of cross-reactivity with other protozoan infections, we studied 86 serum samples including (i) 32 individuals with cutaneo us leishmaniasis living in a T. cruzi endemic region of Bolivia, and ( ii) 54 patients from nonendemic area for Chagas' disease, 19 of them w ith kala-azar and 35 others with malaria.