In this lecture, Dr. Carlota Monroy will describe her team’s work with villagers in Guatemala to combat Chagas. Chagas is a parasitic disease that can affect various organs, potentially resulting in death. The parasite is transmitted to humans primarily through insects. Chagas disease is a “forgotten” disease of the poor that affects much of the rural population in Latin America. Dr. Monroy uses a community-based “ecohealth” approach to study the persistence of vector species in human dwellings. Using local technology and skills, and working with local community members (particularly women) her team addresses housing conditions to reduce exposure to insect vectors.

The Chagas disease (American trypanosomiasis) is a tropical parasitic disease found in rural Latin America, spread by blood-sucking (“kissing”) bugs. It causes serious cardiac and gastrointestinal problems in 30-40% of those infected, often leading to death. In Central America, more than five million people are at risk of infection. Some genetic groups of Triatoma dimidiata, the main Chagas disease vector in Central America, are adapted to mud constructed houses, which are typical in poor rural communities. Conventional methods of vector control (spraying of pesticides) are ineffective or require a continuous cycle of repeated application.

Since 2004 her team has applied an ecosystem approach to health for the control of Chagas disease in Guatemala. This “ecohealth” strategy is transdisciplinary, participatory and paid attention to gender considerations. Working with communities, anthropologists, sociologists, architects and engineers, they assessed and prioritized risk factors for Chagas transmission. They then developed house improvement methods using local materials, and by adapting traditional practices. The strategy counteracts risk factors that promote the presence of vectors. Community participation and education were key factors for success. Dr. Monroy’s team also built capacity in the Ministries of Health in several countries to execute house improvements and addressed domestic animal management, e.g., by constructing wire chicken coops. Vaccination of chickens against major poultry diseases significantly decreased chicken death rates and increased the number of chickens per household, meat consumption, and generated additional income for women.

Several NGOs (WV, USAID, CARE, FAO-PESA, PRESANCAII) have taken up this Ecohealth approach and have helped improve more than 4000 houses in Central America. Results include decreased vector infestation, a shift of blood sources from humans to chickens, and relocation of domestic animals outside of houses. Geohelminth infections in children from intervention villages were significantly reduced after floor replacement. Home improvements and animal management proved effective in the elimination of house infestations by bugs, in reducing human-vector contact, and as an overall well-being strategy.