Provision of bednets and water filters to delay HIV-1 progression: cost-effectiveness analysis of a Kenyan multisite study.
OBJECTIVE
To estimate the effectiveness, costs and cost-effectiveness of providing long-lasting insecticide-treated nets (LLINs) and point-of-use water filters to antiretroviral therapy (ART)-naïve HIV-infected adults and their family members, in the context of a multisite study in Kenya of 589 HIV-positive adults followed on average for 1.7 years.


METHODS
The effectiveness, costs and cost-effectiveness of the intervention were estimated using an epidemiologic-cost model. Model epidemiologic inputs were derived from the Kenya multisite study data, local epidemiological data and from the published literature. Model cost inputs were derived from published literature specific to Kenya. Uncertainty in the model estimates was assessed through univariate and multivariate sensitivity analyses.


RESULTS
We estimated net cost savings of about US$ 26 000 for the intervention, over 1.7 years. Even when ignoring net cost savings, the intervention was found to be very cost-effective at a cost of US$ 3100 per death averted or US$ 99 per disability-adjusted life year (DALY) averted. The findings were robust to the sensitivity analysis and remained most sensitive to both the duration of ART use and the cost of ART per person-year.


CONCLUSIONS
The provision of LLINs and water filters to ART-naïve HIV-infected adults in the Kenyan study resulted in substantial net cost savings, due to the delay in the initiation of ART. The addition of an LLIN and a point-of-use water filter to the existing package of care provided to ART-naïve HIV-infected adults could bring substantial cost savings to resource-constrained health systems in low- and middle-income countries.