Mpumalanga lab data point to brucellosis surveillance hotspots

Routine laboratory surveillance data from Mpumalanga Province, South Africa, suggest bovine brucellosis detection by Rose Bengal Test (RBT) wasn’t evenly distributed from 2021 through 2024. In the newly published analysis, researchers reviewed submissions handled by the Mpumalanga Provincial Veterinary Laboratory and found that RBT positivity varied over time, with a notable spike in 2023 before dropping back toward earlier levels, and that positivity also differed by district and season. The authors argue that routinely collected lab data, which are often underused, can help identify higher-risk periods and places for targeted surveillance in an endemic setting. Similar lessons are showing up in other endemic contexts: a study of aborting nomadic sheep and goats in southeastern Türkiye found 20.99% positivity by RBPT and 24.78% by indirect ELISA, with 19.53% positive on both tests and treated as confirmed positive, underscoring both the usefulness and the limits of screening-only data. (pmc.ncbi.nlm.nih.gov)

Why it matters: For veterinary professionals, the study reinforces that passive surveillance datasets can still yield practical signals for field action, especially where brucellosis remains endemic and resources are limited. In South Africa, bovine brucellosis is a controlled animal disease, heifer vaccination is mandated, and positive herds face movement and control measures, so better use of provincial lab data could help focus testing, vaccination follow-up, biosecurity, and public health messaging in areas with repeated positivity. The caveat is that RBT is a screening tool, and the authors note confirmatory testing was not systematically available for all submissions during the study period. That point aligns with findings from Türkiye, where RBPT and i-ELISA were broadly concordant but still significantly different, supporting the need for more specific follow-up testing in endemic settings. (pmc.ncbi.nlm.nih.gov)

What to watch: Watch for follow-on work that pairs RBT surveillance with confirmatory testing, herd-level risk factors, and more explicit One Health planning in Mpumalanga and other South African provinces. It will also be worth watching whether surveillance programs borrow from other brucellosis work beyond cattle: for example, a four-year shelter-dog study in southern Italy found Brucella canis seroprevalence of 17.3%, with year and province affecting antibody intensity even when they did not predict simple seropositivity, suggesting that tracking antibody magnitude as well as positive/negative status may help detect changing infection pressure earlier. (pmc.ncbi.nlm.nih.gov)