Diagnosis of ovine enzootic abortion using an indirect ELISA (rOMP91B iELISA) based on a recombinant protein fragment of the polymorphic outer membrane protein POMP91B of Chlamydophila abortus

Chamydophila abortus is of major economic importance worldwide as one of th e principal causes of abortion in sheep. Serological diagnosis of infection by the complement fixation test (CFT) is complicated by false positive rea ctions resulting from cross-reactive antibodies to Chlamydophila pecorum. T o improve diagnosis an indirect enzyme-linked immunosorbent assay (iELISA) based on a recombinant protein fragment of the C. abortus polymorphic outer membrane protein POMP91B (rOMP91B iELISA) was assessed using a panel of 28 1 sera from experimentally and naturally infected sheep. The iELISA perform ed well, being more sensitive (84.2%) and specific (98.5%) than the CFT. Fu rthermore, the iELISA was better at differentiating C. abortus- from C. pec orum-infected animals. The new rOMP91B iELISA test will prove a valuable to ol For the routine serodiagnosis of C. abortus infection, (C) 2001 Federati on of European Microbiological Societies. Published by Elsevier Science B.V . All rights reserved.