Cost and cost-effectiveness analysis of mass drug administration compared to school-based targeted preventive chemotherapy for hookworm control in Dak Lak province, Vietnam.

Background: School-based targeted preventive chemotherapy (PC), the main strategy for soil-transmitted helminths (STH) control, excludes other at-risk populations including adults and preschool children. Mass drug administration (MDA), covering all age groups, would bring additional health benefits but also requires greater investment. This cost survey and cost-effectiveness analysis compared MDA with school-based targeted PC for STH control in Dak Lak, Vietnam, where STH are endemic. Methods: A cost survey was conducted in 2020 to estimate the total and per person economic and financial cost of each strategy. Monte Carlo simulation accounted for uncertainty in cost estimates. The primary effectiveness measure was hookworm-related disability-adjusted life years (DALYs) averted, and secondary measures were hookworm infection-years averted and moderate-to-heavy intensity hookworm infection-years averted. A Markov model was used to determine the incremental cost-effectiveness ratio (ICER) of MDA compared to school-based targeted PC using a government payer perspective and a ten-year time horizon. One-way and probabilistic sensitivity analyses (PSA) were performed. Costs are reported in 2020 USD ($). Findings: The economic cost per person was $0.27 for MDA and $0.43 for school-based targeted PC. MDA in Dak Lak will cost $472,000 per year, while school-based targeted PC will cost $117,000. Over 10 years, MDA is estimated to avert an additional 121,465 DALYs; 4,019,262 hookworm infection-years, and 765,844 moderate-to-heavy intensity hookworm infection-years compared to school-based targeted PC. The ICER was $28.55 per DALY averted; $0.87 per hookworm infection-years averted, and $4.54 per moderate-to-heavy intensity hookworm infection-years averted. MDA was cost-effective in all PSA iterations. Interpretation: In areas where hookworm predominates and adults suffer a significant burden of infection, MDA is cost effective compared to school based targeted PC and is the best strategy to achieve global targets. Funding: The project was funded by the National Health and Medical Research Council (NHMRC) of Australia (Project Grant APP1139561) and JPCDT was supported by a UNSW Scientia PhD Scholarship.