Abstract
Porcine brucellosis is listed as categories D and E disease in the regulation (EU) 2018/1882, Animal Health Law (AHL). The AHL (prescribes measures in the EU member states for trade conditions and surveillance/ notification. Moreover, according to the regulation, the diagnostic methods should be validated in accordance with international standards for this purpose. Rose Bengal and Complement fixation tests are mainly used for Brucella abortus, B. melitensis and B. suis serological diagnosis. Although performed for brucellosis diagnosis in domestic animals, these tests were initially validated only for bovines. Furthermore, in pigs, it seems to have a high level of false positive serological reactions (FPSRs) caused primarily by Yersinia enterocolitica O:9. To date, no method for porcine brucellosis diagnosis has been validated for the intended purpose according to current World Organisation for Animal Health (founded as WOAH) principles. This study aims to compare the FPSRs performances of five ELISA kits for porcine brucellosis diagnosis [1IDScreen Brucella suis, 2ID Screen Brucellosis serum indirect multi-species (Innovative Diagnostics, France), 3Ingezim Brucella Compac, 4Ingezim Brucella Porcina (Ingenasa, Spain), and 5Brucella abortus/melitensis/suis DIVA (VMRD, USA)] comparing to Rose Bengal (RBT) and Complement Fixation test (CFT). A panel of 88brucellosis-free pig sera from artificial insemination centers6 in France, that presented a serological positive reaction in at least one method (RBT, CFT or i-ELISA), were examined for analytical specificity (cross-reaction activity). The false positive reactions were observed in all tests: RBT (80/88), CFT (56/85) and 3 with anti-complementary reaction, Kit7 (6/88), Kit8 (55/88), Kit9 (81/88), Kit10 (44/88), and Kit11 (60/88). The RB and CF methods for brucellosis diagnosis showed a high level of cross-reaction comparing with ELISA kits for porcine brucellosis. ELISA is a robust and simple test to perform, however each ELISA kit presents different performances. Therefore, validation of this method for porcine species is needed for surveillance and trade.
