Cost-Effectiveness of Household Contact Investigation for the Detection of Tuberculosis in Vietnam: A Cluster Randomised Controlled Trial

Background: Active case finding (ACF) is recommended as an important strategy to control tuberculosis (TB), particularly in high prevalence low- and middle- income (LMIC) settings. However, the costs and cost-effectiveness ACF have been uncertain, in the absence of evidence from randomised controlled trials (RCT). We investigated the cost-effectiveness of ACF in Vietnam based on the findings of a recent large-scale trial. Methods: We conducted a pragmatic cluster RCT conducted in 70 districts in eight provinces of Vietnam, comparing ACF plus standard passive case finding (PCF) to PCF alone among the household contacts of patients with TB. In the intervention group, participants were invited to attend screening at baseline, 6, 12 and 24 months. Healthcare costs were determined using a standardised national costing survey. The primary outcome was DALYs averted over a 24-month period. Secondary outcomes were the cumulative incidence of registered and smear-positive cases of tuberculosis among contacts. Findings: 10,069 and 15,638 household contacts were recruited to the intervention and control groups, respectively. The cost of ACF over a 24month period was $181 (95% CI 178 - 185) (2017 $USD) per person, compared to $83 (95% CI 83 - 83) per person for the control group. The incremental cost-effectiveness ratio was $544 (95% CI 330 - 1,375) per DALY averted. Interpretation: ACF was shown to be highly cost-effective in a high prevalence setting. Investment in the wide-scale implementation of this programme in Vietnam, and comparable settings, should be strongly supported. Funding: Australian National Health and Medical Research Council Declaration of Interests: There are no conflicts of interest to disclose Ethics approval was provided by the Human Research Ethics Committee at the University of Sydney and the Scientific Committee of the Vietnam Ministry of Health. The trial was registered prospectively with the Australian and New Zealand Clinical Trials Registry (ACTRN 12610000600044).