Brucella Diagnostics in Endemic Areas: Evaluation of Point-of-Care Kits and the Need for Alternative Diagnostic Tests

Brucellosis is a significant public health challenge in Kenya, particularly in pastoralist communities where the disease is endemic. Reliable and accurate point-of-care diagnostics are essential for timely case identification and effective disease management. The Febrile Brucella Agglutination Test (FBAT) is commonly used for diagnosis of brucellosis in Kenya, but concerns have been noted about its diagnostic accuracy, prompting an independent evaluation. The aim of this study was to compare the diagnostic performance of five FBAT kits with a commercial Enzyme-Linked Immunosorbent Assay (ELISA) as the reference standard, and to build local laboratory capacity for in-house kit validation for the Kajiado County laboratory staff. A total of 200 serum samples (100 ELISA-confirmed positives and 100 negatives) were tested using the FBAT kits. Each kit was evaluated for its ability to detect antibodies to both B. abortus and B. melitensis antigens. Diagnostic performance indicators, including sensitivity, specificity, and Cohen’s Kappa, were calculated, and McNemar’s test was applied to assess concordance with the ELISA results. Overall, none of the FBAT kits proved to have acceptable sensitivity and specificity compared to ELISA. We conclude that FBAT kits are not sufficient for the diagnosis of brucellosis and that alternative diagnostics should be considered.