Towards the validation of a RT-PCR assay for the detection of Brucella DNA in different types of animal samples
Gorde:
| Egileak: | , , , , , |
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| Formatua: | artículo original |
| Egoera: | Versión publicada |
| Argitaratze data: | 2026 |
| Deskribapena: | Brucellosis due to Brucella melitensis remains a high-priority zoonosis worldwide, with substantial health and economic consequences driven by bacterial shedding in livestock during abortions and in milk. Historically, surveillance and control efforts have been constrained by diagnostic limitations: serological assays often yield false positives due to cross-reactivity, while bacteriological culture, despite being definitive, is slow, labor- intensive, susceptible to false negatives, and requires high-level biocontainment measures. These challenges obstruct effective surveillance, accurate prevalence estimation, and timely response measures thereby prolonging economic losses. This study validates a highly sen- sitive and specific real-time PCR assay targeting the IS711 insertion sequence and the B. melitensis-specific gene BMEII0636, assessing the diagnostic performance in experimen- tally infected goats. Tissue samples (retropharyngeal, parotid, and submandibular lymph nodes), placenta, milk, and vaginal swabs were collected at the time of abortion from goats conjunctively inoculated with 1.1×10 CFU of B. melitensis 16M (n=20). Brucella presence was confirmed by culture. Control samples were obtained from naive goats from a certified brucellosis-free herd (n=11). All tissue samples were blinded and directly tested via real-time PCR. This assay demonstrates high sensitivity — 93.4% for IS711 and 94.2% for BMEII0636— with no false positives in culture-negative controls. Limits of detection were 8.75×10¹ gene copies for IS711 and 1.25×10 for BMEII0636. Furthermore, the time required to obtain results was shortened from several days with bacteriological culture to a few hours using this method. These findings support the integration of this validated PCR assay into brucellosis surveillance frameworks, enabling accurate prevalence estima- tion, timely prevention and control interventions, and reduced zoonotic transmission risk. Notably, placenta, milk, and vaginal swabs, which are easily collected and yield a high bacterial load, showed strong diagnostic performance, underscoring their utility for field surveillance and rapid-response protocols. This approach is especially critical for enhanc- ing One Health-aligned control strategies worldwide. |
| Herria: | Portal de Revistas UNA |
| Erakundea: | Universidad Nacional de Costa Rica |
| Repositorio: | Portal de Revistas UNA |
| Hizkuntza: | Inglés |
| OAI Identifier: | oai:www.revistas.una.ac.cr:article/22837 |
| Sarrera elektronikoa: | https://www.revistas.una.ac.cr/index.php/veterinaria/article/view/22837 |
| Gako-hitza: | Brucella melitensis real-time PCR diagnostics |