The aim of this study was to develop a 16S-23S ribosomal deoxyribonucleic acid internal
transcribed spacer (ITS) quantitative polymerase chain reaction (qPCR) assay for the early diagnosis
and rapid screening of brucellosis. Blood, milk, and tissue samples were spiked with B. abortus biovar
1 (B01988-18 strain) to determine the analytical sensitivity and specificity of the assay. The 95% limit
of detection of the ITS qPCR assay was highest in tissue, followed by blood, then milk, i.e., 0.48, 4.43,
and 15.18 bacteria/PCR reaction, respectively. The diagnostic performance of the assay was compared
to the Brucella cell surface protein (BCSP) 31 qPCR assay and bacterial culture. Out of 56 aborted
foetal tissue samples from bovine, ovine, and caprine, 33% (19/56) were positive for Brucella spp.
The sensitivity and specificity of the ITS qPCR assay was 87% and 95% respectively, compared
to 92% and 89% for the BCSP31 qPCR assay and 47% and 55% for bacterial culture, respectively.
The assay was e cient, sensitive, and specific, making it a valuable tool in the early detection of the