Roadmap for the development of diagnostic test for bTB

What are we trying to achieve and why? What is the problem we are trying to solve?

The detection of the pathogen genome as a marker of infection.

What are the scientific and technological challenges
(knowledge gaps needing to be addressed)?

• Lack of accepted gold standard or Composite Reference Standard.
• The most appropriate sample to use.
• Efficient release of the organism from its intracellular location.
• Avoidance/removal of amplification inhibitors.
• Quality assurance – test repeatability and reproducibility.
• Cost effectiveness.
• Detection in biological samples including milk and faeces.
• The most suitable primers and platform.
• Risk of not having a pan-M. bovis gene sequences.

What approaches could/should be taken to address the research question?

• Objective evaluation of candidate methods on reference samples.
• Consider latent class analyses.
• Cepheid GeneXpert and Ultra used in human TB reference labs.
• Follow STARD and QUADAS-2 guidelines for reporting and designing diagnostic accuracy studies.

What else needs to be done before we can solve this need?

Sequencing of a range of M. bovis isolates from different territories and areas.

Existing knowledge including successes and failures