Evaluation of Indirect and Avidin-Biotin Enzyme Linked Immunosorbent Assays for Detection of Anti-Listeriolysin O Antibodies in Bovine Milk Samples

• Published in: Zoonoses and public health 2007-10, Vol.54 (8), p.301-306
• Main Authors: Kalorey, D. R., Kurkure, N. V., Warke, S. R., Barbuddhe, S. B.
• Format: Article
• Language: English
• Subjects: Animals; Antibodies, Bacterial - analysis; Avidin; Bacteria; Biotin; Bovine; Cattle; Dairy farms; Dairying; enzyme linked immunosorbent assay; Enzyme-Linked Immunosorbent Assay - veterinary; Enzymes; Female; Food Microbiology; Food safety; Humans; India; Listeria monocytogenes; Listeria monocytogenes - immunology; Listeria monocytogenes - isolation & purification; Microbiology; Milk; Milk - microbiology; Predictive Value of Tests; ROC Curve; Sensitivity and Specificity
• ISSN: 1863-1959; 1863-2378
• DOI: 10.1111/j.1863-2378.2007.01066.x

Summary Listeria monocytogenes is a foodborne pathogen that causes a wide spectrum of diseases in humans and animals. Enzyme linked immunosorbent assays (ELISA) [indirect and avidin–biotin (A–B)] for detecting L. monocytogenes antibodies in bovine milk samples (n = 2060) were standardized and evaluated by comparison with bacteriological examination. The tests were standardized by checker board titration. Highly purified listeriolysin O (LLO) was used as an antigen. Receiver operating characteristic (ROC) analysis was performed to decide the cut‐off values. The ROC analysis revealed the sensitivities of indirect and A–B ELISA as 100% and specificities as 97.1 and 99.9% respectively. Listeria monocytogenes was isolated from 105 (5.1%) milk samples collected from 52 farms. Anti‐LLO IgG antibodies were detected from 137 and 112 milk samples when tested by indirect and A–B ELISA respectively. Of the 52 farms screened, 28 (53.8%) yielded one or more isolates of L. monocytogenes and 33 (63.5%) of the farms had one or more animals simultaneously positive by one or both the assays for anti‐LLO antibodies.