Household-contact investigation plus standard passive case finding was more effective than standard passive case finding alone for the detection of tuberculosis in a high-prevalence setting at 2 years. (Funded by the Australian National Health and Medical Research Council; ACT2 Australian New Zealand Clinical Trials Registry number, ACTRN12610000600044 .).

The proportion of households experiencing catastrophic total costs due to TB in Viet Nam is high, which poses a barrier to TB diagnosis and treatment. Based on study results, programme and partners need to identify key areas for policy action and work towards a national policy guide on intervention to reduce TB patient costs.

Background Active case finding is recommended as an important strategy to control tuberculosis, particularly in low-income and middle-income countries with a high prevalence of the disease. However, the costs and costeffectiveness of active case finding are unclear due to the absence of evidence from randomised trials. We assessed the costs and cost-effectiveness of an active case finding strategy in Vietnam, where there is a high prevalence of tuberculosis. MethodsWe conducted an economic evaluation alongside the Active Case Finding in Tuberculosis (ACT2) trial-a pragmatic cluster-randomised controlled trial in 70 districts across eight provinces of Vietnam. Patients aged 15 years and older with smear-positive pulmonary tuberculosis were recruited to the trial if they lived with one or more other household members. Household contacts were verbally invited to the clinic by the index patient with tuberculosis. ACT2 compared a combination of active and passive case finding with usual care (passive case finding) of household contacts of patients with tuberculosis from a health system perspective. Clustering occurred at the district and household level. Districts were the unit of randomisation, and we used minimisation to ensure balance of intervention and control districts within each province. In the intervention group, participants were invited to attend screening at baseline, 6 months, 12 months, and 24 months. We determined health-care costs with a standardised national costing survey and reported results in 2017 $US. The primary outcome of our study was disability-adjusted life years (DALYs) averted over a 24-month period. ACT2 was registered prospectively with the Australian and New Zealand Clinical Trials Registry, number ACTRN126.100.00600044.

Contacts of MDR-TB patients have a high risk of developing TB. Measures to reduce Mycobacterium tuberculosis transmission and accelerate the detection of disease among high-risk contacts should be prioritised to curb the MDR-TB epidemic.