Brucellosis in a Camel Herd: The Role of Missed Vaccination and Illegal Imports

This study aimed to detect the presence of Brucella spp. DNA in aborted camel fetuses from a dairy herd in Meybod, Yazd Province, Iran, using genus-specific PCR. The broader objective was to assess the epidemiological importance of camel brucellosis in a region with limited surveillance and no targeted vaccination programs for camels. A total of 50 aborted fetuses from a single Camelus dromedarius herd were examined. Fetal abomasal contents were collected and tested using Modified Ziehl-Neelsen staining, followed by molecular confirmation via polymerase chain reaction (PCR) targeting the IS711 gene of Brucella spp. DNA was extracted using a commercial tissue DNA kit, and PCR conditions were optimized for specificity. Positive and negative controls were included in each PCR run to ensure reliability and prevent contamination. Modified Ziehl-Neelsen staining revealed Brucella-like organisms in 82% (41/50) of the samples. PCR confirmed the presence of Brucella DNA in 92% (46/50) of the fetal tissues, indicating a high prevalence of infection in the herd. While 72% of the samples tested positive in both Modified Ziehl-Neelsen staining and PCR assays, 2% were negative by Modified Ziehl-Neelsen staining but positive by PCR. This study reveals an unusually high rate of Brucella spp. in aborted fetuses from a single camel herd, suggesting an active outbreak likely exacerbated by illegal livestock movement and lack of camel surveillance. Molecular detection confirms infection, although species-level identification was not performed. These findings highlight the urgent need for targeted camel vaccination, enhanced molecular surveillance, and stricter control over cross-border animal trade.