Science with Societal Implications: Detecting Mycobacterium Tuberculosis in Africa

Abstract

Mycobacterium tuberculosis (Mtb) is one of the world’s leading infectious killers and a disease that disproportionately affects the global poor. Diagnosing tuberculosis disease (TB) with confidence remains an elusive task, especially in resource-limited settings such as those throughout most of Africa. Most diagnostic protocols lack both speed and accuracy, as current methods rely on a combination of screening and confirmatory tests including symptom-based questionnaires, direct smear and microscopy, mycobacterial culture, and chest radiograph. The Xpert® MTB/RIF (Xpert) assay is a polymerase chain reaction (PCR)-based method for TB diagnosis. This assay presents an exciting prospect as a point-of-care (POC) or near-POC test; however, the assay cannot be implemented without changes in budgets, staffing, and infrastructure of existing primary care clinics in the region. This report provides a summary of the Xpert technology and both the benefits and challenges of implementation as a POC test in resource-limited settings.