Ovine echinococcosis: I. Immunological diagnosis by enzyme immunoassay

• Autores: Gatti, Antonio; Alvarez, Angela Rosa; Araya, Daniel; Mancini, Sergio; Herrero, Eduardo; Santillan, Graciela; Larrieu, Edmundo
• Año de publicación: 2007
• Idioma: inglés
• Tipo de recurso: artículo
• Fuente: Veterinary parasitology 2007;143(2):112-121
• Materia: Equinococosis; Ovinos; Pruebas Inmunológicas; Técnicas para Inmunoenzimas
• Institución: Administración Nacional de Laboratorios e Institutos de Salud "Dr. Carlos G. Malbrán"

Fil: Gatti, Antonio. Ministerio de Salud Provincia de Río Negro; Argentina.
Fil: Alvarez, Angela Rosa. Universidad Nacional de La Pampa. Facultad de Veterinaria; Argentina.
Fil: Araya, Daniel. Universidad Nacional de La Pampa. Facultad de Veterinaria; Argentina.
Fil: Mancini, Sergio. Ministerio de Salud Provincia de Río Negro; Argentina.
Fil: Herrero, Eduardo. Ministerio de Salud Provincia de Río Negro; Argentina.
Fil: Santillan, Graciela. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Departamento de Parasitología; Argentina.
Fil: Larrieu, Edmundo. Universidad Nacional de La Pampa. Facultad de Veterinaria; Argentina.
Immunodiagnosis in sheep presents problems of sensitivity and specificity, limiting its applicability in surveillance systems. The objective of this study was to develop a sensitive, specific and accessible technique for diagnosing cystic echinococcosis in naturally infected sheep and to evaluate the validity of necropsy as a reference test. A total of 247 sheep were studied at slaughterhouses, confirming the parasitological diagnosis with histology. Serum was processed with enzyme immunoassay (EIA) using three antigen preparations: total hydatid liquid (LHT), purified fraction of LHT (S2B) and purified lipoprotein (B). Western Blot (WB) was used as a control. EIA proved effective for differentiating Echinococcus granulosus from larval stage of Taenia hydatigena and intestinal cestodes in all three antigen preparations. Serums from macroscopically negative sheep were reactive to EIA and positive with WB. In the whole flock, sensitivity was 89.2% for LHT, 80.0% for S2B and 86.4% for B. Sensitivity in lambs was 78.6% for LHT, 75.0% for S2B and 64.3% for B. Macroscopic diagnosis at the time of slaughter was found to have limitations as a reference test for immunodiagnosis of cystic equinococcosis in sheep, so it was necessary to include histology and WB as reference tests. LHT was the antigen preparation of greatest value and EIA proved to be a sensitive and specific technique, adequate for surveillance systems and for evaluating control programmes.