The Costs of Preventing and Treating Chagas Disease in Colombia

Abstract
The objective of this study is to report the costs of Chagas disease in Colombia, in terms of vector disease control programmes and the costs of providing care to chronic Chagas disease patients with cardiomyopathy. Data were collected from Colombia in 2004. A retrospective review of costs for vector control programmes carried out in rural areas included 3,084 houses surveyed for infestation with triatomine bugs and 3,305 houses sprayed with insecticide. A total of 63 patient records from 3 different hospitals were selected for a retrospective review of resource use. Consensus methodology with local experts was used to estimate care seeking behaviour and to complement observed data on utilisation. The mean cost per house per entomological survey was $4.4 (in US$ of 2004), whereas the mean cost of spraying a house with insecticide was $27. The main cost driver of spraying was the price of the insecticide, which varied greatly. Treatment of a chronic Chagas disease patient costs between $46.4 and $7,981 per year in Colombia, depending on severity and the level of care used. Combining cost and utilisation estimates the expected cost of treatment per patient-year is $1,028, whereas lifetime costs averaged $11,619 per patient. Chronic Chagas disease patients have limited access to healthcare, with an estimated 22% of patients never seeking care. Chagas disease is a preventable condition that affects mostly poor populations living in rural areas. The mean costs of surveying houses for infestation and spraying infested houses were low in comparison to other studies and in line with treatment costs. Care seeking behaviour and the type of insurance affiliation seem to play a role in the facilities and type of care that patients use, thus raising concerns about equitable access to care. Preventing Chagas disease in Colombia would be cost-effective and could contribute to prevent inequalities in health and healthcare. Chagas disease is one of the most important vector-transmitted diseases in Latin America. Many patients with Chagas go undiagnosed for years, and because symptoms of the chronic condition are similar to those of other cardiac conditions, the burden of the disease is not evident. This leads to underestimation of the burden that Chagas disease places on healthcare resources, which in many cases translates into inadequate prioritisation for prevention. This study assessed the cost of Chagas disease in Colombia in comparison to the cost of prevention. Measuring the cost of treatment for Chagas disease is challenging. In this study we used a method that combines retrospective review of costs for prevention activities and for treatment of chronic Chagas disease patients, and we estimated utilisation of services using experts' consensus. We found that the cost of treating Chagas disease is substantial, even though many people are not receiving appropriate care. On the other hand, we show that preventing Chagas disease transmission through insecticide spraying activities is affordable in Colombia and therefore should be conducted more systematically. This study provides the basic inputs to conduct a full economic evaluation of Chagas disease prevention.