Enfermedad de Chagas: impacto del programa de control del triatoma infestans en la comuna de Alto del Carmen provincia de Huasco III Región Atacama de Chile / Chagas' disease: impact of triatoma infestans control program in Alto del Carmen of Huasco, III region Atacama, Chile

RESUMEN

A control program of triatoma infestans has been carried out in Alto del Carmen, an endemic chagasic rural county in the III Region, Chile. The program started in 1988 with an attack phase consisting in a masshouse spraying with residual insecticide, followed by an entomological surveillance phase with health education for community participation and vector detection in eventually reinfested houses. A yearly evaluation in 1992, 1993, 1994 and 1995 was carried out in order to determine the effectiveness of vector control activities. In 1992, 24,1 percent of dwellings was infected, whereas in 1993, 1994 and 1995 the infestation rates were 3,9 percent, 2,8 percent and 4,0 percent respectively. The similar infestation rates found in 1993, 1994 and 1995 suggest passive dispersion of triatomas from areas without suveillance. Additionally, in 1994, 110 (16,0 percent) out of 688 examined people resulted serologically positive. It is noteworthy that all of the children in the 0-4 year age group, born after the attack phase, resulted serologically negative. This fact may indicate the interruption of vectorial transmission of Chagas's disease in Alto del Carmen county. It is concluded that the control activities perfored in the county constitute god strategies to the Nacional Program of Control of triatoma infestans, but for the sucess of such a program it is necessary to integrate the effort of all endemic areas with an active community participation