Cost-effectiveness of community mobilization (Camino Verde) for dengue prevention in Nicaragua and Mexico: a cluster randomized controlled trial.

BACKGROUND: We assessed the cost-effectiveness of Camino Verde, a community-based mobilization strategy to prevent and control dengue and other mosquito-borne diseases. A cluster-randomized controlled trial in Managua, Nicaragua, and in three coastal regions in Guerrero, Mexico (75 intervention and 75 control clusters), Camino Verde used non-governmental community health workers, called brigadistas, to support community mobilization. This donor-funded trial demonstrated reductions of 29.5% (95% confidence interval, CI: 3.8%-55.3%) on dengue infections and 24.7% (CI: 1.8%-51.2%) on self-reported cases. METHODS: We estimated program costs through a micro-costing approach and semi-structured questionnaires. We show results as incremental cost-effectiveness ratios (ICER) for costs per disability-adjusted life-year (DALYs) averted and conducted probabilistic sensitivity analyses. FINDINGS: The Camino Verde trial spent $16.72 in Mexico and $7.47 in Nicaragua per person annually. We found an average of 910 (CI: 487-1 353) and 500 (CI: 250-760) dengue cases averted annually per million population in Mexico and Nicaragua, respectively, compared to control communities. The ICER in Mexico was $29 618 (CI: 13 869-66 898) per DALY averted, or 3.0 times per capita GDP. For Nicaragua, the ICER was $29 196 (CI: 14 294-72 181) per DALY averted, or 16.9 times per capita GDP. INTERPRETATION: Camino Verde, as implemented in the research context, was marginally cost-effective in Mexico, and not cost-effective in Nicaragua, from a healthcare sector perspective. Nicaragua's low per capita GDP and use of extra-governmental management personnel weakened the cost-effectiveness results. Achieving efficiencies by incorporating Camino Verde activities into existing public health programs would make Camino Verde cost-effective.