Comparison of counterelectrophoresis the enzyme-linked immunosorbent assay, and Kato fecal examination for the diagnosis of fascioliasis in infected mice and rabbits.

The enzyme-linked immunosorbent assay (ELISA), counterelectrophoresis (CEP), and Kato thick-smear stool examinations were used to follow Fasciola hepatica infections in mice and rabbits given or not given chemotherapy. In both mice and rabbits antibody levels were evident by ELISA within 2 weeks of infection, rising to high levels 2 weeks later. Precipitins monitored by CEP were also evident by 2 weeks of infection in mice, but developed more slowly (4-6 weeks) in rabbits. Eggs of F. hepatica were detected at 6-8 weeks of infection in mice and 8-10 weeks in rabbits. In mice with fascioliasis both ELISA and CEP antibody levels tended to drop by 8 weeks of infection, but in rabbits they remained strongly positive for 34 weeks. Mice treated with rafoxanide at 5 weeks of infection rapidly (3-4 weeks) became Kato-, CEP-, and ELISA-negative. Rabbits treated at 26 weeks of infection still had high antibody levels by ELISA 8 weeks later but were Kato-negative and had low precipitin (CEP) levels. ELISA was most sensitive in detecting early infection but CEP was the best indicator of chemotherapeutic success.