title: Evaluation of four commercial enzyme-linked immunosorbent assays for the diagnosis of bovine paratuberculosis in Chilean dairy herds.
abstract: The accuracy of 4 commercial enzyme-linked immunosorbent assays (ELISAs) for diagnosis of bovine paratuberculosis was compared using sera from 53 Mycobacterium avium subsp. paratuberculosis (MAP) fecal culture-positive dairy cows (cases) and sera from 345 dairy cattle resident in 11 fecal culture-negative herds on 2 consecutive occasions 1 year apart (controls). The specificity of all 4 ELISA kits was >99%, and their diagnostic sensitivity ranged from 30.2% to 41.5%. Pairwise comparison of ELISAs found no significant differences (McNemar's chi-square test > 0.05), and assay agreement for categorical assay interpretation (positive or negative) was high (>98%) with kappa values ranging from 0.84 to 0.95. Receiver operating characteristic (ROC) curve analysis and the corresponding area under the ROC curves indicate that kit B had the highest overall accuracy. Thus, all 4 ELISA kits for bovine paratuberculosis had comparable accuracy when tested on Chilean dairy cattle, with kit B having a slight statistical advantage based on ROC area under the curve analysis. This suggests that any of the 4 kits could be appropriate for herd certification and for paratuberculosis control programs on Chilean dairy cattle.
authors.affiliation: Microbiology Department, Faculty of Sciences, Universidad Austral de Chile, Valdivia, Chile.
authors.forename: M Paulina
authors.initials: MP
authors.lastname: Fry
authors.forename: Juan
authors.initials: J
authors.lastname: Kruze
authors.forename: Michael T
authors.initials: MT
authors.lastname: Collins
mesh_terms: D000818:Animals; D002417:Cattle; D002677:Chile; D003612:Dairying; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary*; D010283:Paratuberculosis / Q000175:diagnosis*