CASE 12: Controlling Chagas disease in the southern cone of South America

Health Condition: In the early 1990s, Chagas disease was ranked as the most serious parasitic disease in Latin America. The disease was endemic in all seven countries in the southern cone, and wavering political commitment and reinfestation of the insect vectors across borders hampered efforts to control disease. Today an estimated 11 million people in 15 Latin American countries are infected with Chagas disease. The disease also plagues northern South America, Central America, and Mexico, as well as the remaining pockets in the southern cone.

Intervention or Program: The Southern Cone Initiative to Control/Eliminate Chagas was launched in 1991, under the leadership of the Pan American Health Organization. Spray teams operated by ministries of health have treated more than 2.5 million homes across the region with long-lasting pyrethroid insecticides. Houses in poor rural areas have been improved to eliminate the insect's hiding places, and blood is screened for Chagas disease.

Impact:

• Incidence in the seven countries covered by the initiative fell by an average of 94 percent by 2000;
• Overall, the number of new cases on the continent fell from 700,000 in 1983 to fewer than 200,000 in 2000;
• The number of deaths each year from the disease was halved from 45,000 to 22,000; and
• By 2001, disease transmission was halted in Uruguay, Chile, and large parts of Brazil and Paraguay.

Cost and Cost-Effectiveness: Financial resources for the regional program, provided by each of the seven countries, have totaled more than $400 million since 1991. The intervention is considered among the most cost-effective interventions in public health, at just $37 per disability-adjusted life year saved in Brazil.