This cross-sectional epidemiological study will evaluate a novel methodology of tuberculosis (TB) surveillance, determine the prevalence of TB immunoreactivity in young children, adolescents and young adults in Blantyre, Malawi, and determine the risk factors and spatial distribution of TB infection. We intend to recruit children aged 1-5 years old, adolescents 10-17 years, and adults 18-40 years and test them for immunoreactivity to M. tuberculosis using the QIAreach-QFT interferongamma release assay (IGRA). We will recruit from two places: community cross-sectional household testing, and convenience sampling within primary health clinics (PHCs). Results will be used to identify areas of high TB risk in Blantyre, inform targeted interventions, and provide recommendations for future TB surveillance methodologies.