Diagnostic Techniques for Bovine Tuberculosis

Bovine tuberculosis (bTB) is primarily diagnosed ante-mortem by assessing cell-mediated immunity through intradermal tuberculin skin tests, which remain the cornerstone of control programmes worldwide. Complementary assays measure interferon-gamma release from peripheral blood lymphocytes to enhance sensitivity, while serological methods—including enzyme-linked immunosorbent assays and lateral-flow antibody tests—offer rapid, field-adaptable screening. Postmortem confirmation relies on gross lesion inspection, culture, histopathology and polymerase chain reaction to detect Mycobacterium bovis DNA. Advances in proteomic technologies, notably matrix-assisted laser desorption/ionisation mass spectrometry, promise non-invasive, same-day classification of infection status. Molecular techniques such as whole-genome sequencing and targeted sequencing underpin outbreak tracing and antimicrobial resistance profiling. Emerging defined antigens and peptide cocktails aim to reduce cross-reactivity with non-tuberculous mycobacteria, improving specificity without compromising sensitivity. Integration of multidisciplinary approaches supports more efficient herd surveillance, underpins eradication efforts and addresses One Health concerns by mitigating zoonotic transmission risks.

Research from Nature Portfolio

Recent studies have evaluated novel defined antigens for intradermal testing to overcome the limitations of purified protein derivatives. In a guinea pig model, single and comparative intradermal tests using a peptide cocktail combining ESAT-6, CFP-10 and Rv3615c or recombinant fusion protein demonstrated full specificity for Mycobacterium bovis and M. caprae, while classic bovine and avian PPD induced nonspecific responses to several environmental mycobacteria. Comparative interpretation reduced false positives, and the peptide-based reagents maintained sensitivity equivalent to standard assays. These findings support the gradual replacement of crude PPD with defined antigen formulations to enhance diagnostic accuracy in bTB control programmes.

Research from all publishers

A liquid atmospheric pressure matrix-assisted laser desorption/ionisation mass spectrometry (LAP-MALDI MS) approach has been developed to detect bTB infection from nasal swabs in cattle within hours. By applying supervised linear discriminant analysis to spectral biomarkers, researchers achieved 75% sensitivity and 90% specificity in a single visit, matching the performance of conventional skin tests. This non-invasive platform offers the potential for rapid on-farm decision-making.

Genomic analyses of RD1-encoded esxA and esxB gene orthologs across over 100 Mycobacteriaceae species revealed widespread presence of ESAT-6 and CFP-10 homologues in non-tuberculous mycobacteria. This underlines the risk of cross-reactive immune responses in cell-mediated immunity assays and motivates the search for more specific antigens outside the RD1 region to refine immunodiagnostic tests.

A comprehensive review has synthesized conventional and emerging diagnostics, discussing cellular assays, serology, culture, histopathology, PCR and next-generation sequencing. It highlights the value of combining tests to overcome variable sensitivity and specificity, addresses the challenge of multidrug-resistant M. bovis, and underscores the role of bioinformatics in molecular epidemiology and resistance detection.

Diagnostic Techniques for Bovine Tuberculosis publication trend

The graph below shows the total number of articles in diagnostic techniques for bovine tuberculosis across all publications each year (not limited to Nature Index journals).

Technical terms

Tuberculin skin test (TST): Intradermal injection of purified protein derivative to elicit a delayed-type hypersensitivity response indicating bTB exposure.

Interferon-gamma release assay (IGRA): Measurement of interferon-gamma released by T-cells in whole blood after stimulation with mycobacterial antigens.

Purified protein derivative (PPD): Crude antigen mixture derived from Mycobacterium bovis used in skin tests to detect cell-mediated immunity.

ESAT-6/CFP-10: Early secreted antigens of the RD1 region, commonly used as defined targets in immunodiagnostic assays.

LAP-MALDI MS: Liquid atmospheric pressure matrix-assisted laser desorption/ionisation mass spectrometry, a rapid proteomic technique for biomarker profiling.

References

1. LAP-MALDI MS Profiling and Identification of Potential Biomarkers for the Detection of Bovine Tuberculosis. Journal of Agricultural and Food Chemistry (2023).
2. The Presence of esat-6 and cfp10 and Other Gene Orthologs of the RD 1 Region in Non-Tuberculous Mycobacteria, Mycolicibacteria, Mycobacteroides and Mycolicibacter as Possible Impediments for the Diagnosis of (Animal) Tuberculosis. Microorganisms (2024).
3. Differences in skin test reactions to official and defined antigens in guinea pigs exposed to non-tuberculous and tuberculous bacteria. Scientific Reports (2023).
4. Review on Bovine Tuberculosis: An Emerging Disease Associated with Multidrug-Resistant Mycobacterium Species. Pathogens (2022).