Comparative analysis of the costs and benefits of alternative disease control strategies: vector control versus human case finding and treatment.

Recent estimates of the costs of detection and treatment and vector control for human trypanosomiasis are summarized and the main factors influencing their levels discussed. In order to proceed to an economic analysis a benefit unit is defined as equivalent to one year's infection avoided due to the control strategy for one person. Different monetary values could be assigned to this unit and it has the advantage of being easily integrated into epidemiological models, being represented by the difference in prevalence with and without control. A simple spreadsheet-based economic model was developed to analyse the relative economic performance of the two control strategies in terms of the cost per benefit unit obtained. The results demonstrate the sensitivity of the economic performance of each strategy to the epidemiological assumptions made, especially with respect to the existence of an animal reservoir and the evolution of the disease situation in the absence of control. They point to the need to integrate economic and epidemiological models in order to evaluate control options.