Economic evaluation of Wolbachia deployment in Colombia: A modeling study

TL;DR

This study evaluates the economic benefits of using Wolbachia bacteria to reduce dengue in Colombia, finding it to be highly cost-effective and beneficial.

Contribution

The study provides new economic evaluations of Wolbachia deployment in 11 Colombian cities, showing it is cost-effective and beneficial in high-incidence, high-density areas.

Findings

Wolbachia deployment in Cali is projected to save US$4.95 per person and avert 369 DALYs per 100,000 population over 10 years.

Wolbachia is expected to have benefit-cost ratios of US$5.50 in Cali and US$4.68 across all target cities.

Healthcare cost savings alone would offset deployment costs in 9 of 11 cities.

Abstract

Wolbachia are bacteria that inhibit dengue virus replication within the mosquito. A cluster-randomized trial in Indonesia found Wolbachia reduced virologically-confirmed dengue cases by 77.1%. Previous models predicted Wolbachia to be highly cost-effective in Indonesia, Vietnam, and Brazil. To inform decisions about future extensions in Colombia, we performed economic evaluations of potential Wolbachia deployments in 11 target cities.

We assembled the numbers and distribution by severity of reported dengue cases from Colombia’s national disease surveillance system and the health service provision registry (RIPS). An epidemiological panel of three experts estimated the shares of dengue that were non-medical, under-reported, or misreported as another disease. We determined costs (in 2020 US dollars at market prices) of treating dengue illness from the benchmark insurance tariff and RIPS data on treatment services per symptomatic dengue case. Our central estimates projected 10 years of efficacy and focused on Cali, the target city with the highest number of dengue cases.

For Cali, we estimated a net health-sector savings of US$4.95 per person and averting 369 disability-adjusted life years (DALYs) per 100,000 population. From a societal perspective, at 10 years Wolbachia deployment is expected to have highly favorable benefit-cost ratios, with benefits per dollar invested of US$5.50 in Cali and US$4.68 over all target cities.

Over 10 years, Wolbachia is highly beneficial on economic grounds, and almost universally cost saving. The Wolbachia program’s economic benefits exceeded its costs in all 11 cities. The program’s savings in healthcare costs alone would more than offset deployment costs nationally and in 9 of 11 target cities. Wolbachia is likely to be the most cost-effective or cost-saving dengue control option in municipalities with both high incidence of dengue and high population density, whereas areas with high dengue incidence but low population density should consider vaccination.

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