Understanding how tuberculosis spreads from people without symptoms

TB QUEST is a research study investigating a gap in our understanding of tuberculosis: whether people who have the infection but don't feel sick can still spread it to others. Researchers will follow people with tuberculosis and their close contacts over time to track who develops the disease and understand how it spreads.

Current tuberculosis control strategies treat the disease as either dormant (latent) or active with symptoms. However, new evidence suggests some people have active tuberculosis without symptoms, and they may be spreading the disease without knowing it. This study exists to understand whether this middle stage is real, how common it is, and what it means for controlling tuberculosis globally.