Biological Determinants and Epidemiological Consequences of Subclinical Tuberculosis - "Sub-TB Study"

The Sub-TB Project, titled “Biological Determinants and Epidemiological Consequences of Subclinical Tuberculosis,” addresses a critical and emerging challenge in tuberculosis (TB) control—subclinical TB, a form of TB where individuals are infected and may transmit the disease without showing symptoms.

Emerging evidence shows that subclinical TB could play a significant role in ongoing transmission, yet it is often missed during routine screening. The project examines the biological and epidemiological implications of this form of TB, reviews current treatment recommendations and practices in Tanzania, and gathers insights from patients, healthcare workers, and policymakers to inform more effective TB control strategies.

Led by Ifakara Health Institute with funding from Swiss Tropical and Public Health Institute, the Sub-TB Project seeks to strengthen understanding of subclinical TB and inform national treatment strategies.

Project Objectives

The project aims to:

1. Examine treatment recommendations and their implementation for subclinical TB in Tanzania
2. Assess current clinical practices for individuals diagnosed with subclinical TB.
3. Understand patient perspectives, preferences, and motivations regarding subclinical TB management.
4. Evaluate knowledge, attitudes, and practices among healthcare workers and policymakers.

Study Approach

Using a mixed-methods design, the study combines structured surveys, discrete choice experiments (DCEs), in-depth interviews, and follow-up assessments. This approach ensures both quantitative evidence and community-centered insights—reflecting IHI’s emphasis on participatory research and health systems strengthening.

Expected Impact

By generating locally relevant evidence, the Sub-TB Project will:

• Inform national TB guidelines and screening strategies.
• Support symptom-agnostic screening approaches among high-risk populations, including household contacts.
• Contribute to improved TB prevention and transmission reduction efforts in Tanzania.
• Strengthen evidence-based decision-making among policymakers and healthcare providers.