ABSTRACT
Chagas's disease is a parasitic zoonosis with high prevalence in Chile. It is distributed in rural and periurban section in the northern most seven out of thirteen regions in which the country is divided, and affects about 142,000 individuals dispersed in most of the 165 counties sited in the chagasic zone triatoma infestans, intradomiciliary species, is the main and practically exclusive vector of trypanosoma cruzi. Diverse tools be utilized in order to interrupt the domestic cycle of transmission of T. cruzi health education, housing improvement and elimination of vectors by dwelling insecticide sprayings. This last resource has received priority in Chile in the last 12 years. To evaluate the effectivity of the programs for eliminating T. infestans a serological study for Chagas's disease, comprising 8,767 children less than 10 years old from 27 rural counties insecticide sprayed in the last 12 years, was carried out. A global total of 125 (1,4 percent) children resulted positive, figure significantly lower than 5,4 percent found in 1982-1990 in the same age group. Distribution by regions of positive individuals showed a decrease of prevalence in each of them: III Region, from 9,8 to 1,0 percent, IV Region, 7,2 to 2,0 percent, V Region, 5,2 to 1,9 percent, and Metropolitan Region, 1,4 to 0,6 percent. Even though positive children have still been found in 46,7 percent of localities of the studied counties, it is possible to affirm that the vector control programs have been effective and must be maintained, and increased in those localities with T. cruzi infection in children under 10 years of age, with the general aim of eradicate Chagas's disease transmission in Chile before 2000.
Subject(s)
Humans , Animals , Male , Female , Infant , Child, Preschool , Chagas Disease/epidemiology , Pest Control, Biological/statistics & numerical data , Program Evaluation/statistics & numerical data , Triatoma/parasitology , Chagas Disease/transmission , Cross-Sectional Studies , Insecticides , Vulnerable Populations/statistics & numerical data , Urban Population/statistics & numerical data , Serologic Tests , Simple Random Sampling , Trypanosoma cruzi/pathogenicityABSTRACT
La mejor alternativa para reducir los vectores de enfermedades humanas es el control biológico, ya que los insecticidas de origen químico causan daño en los ecosistemas y algunos vectores han presentado resistencia a ellos. Este artículo muestra los diferentes grupos de organismos que ejercen un control natural sobre especies vectores de enfermedades
Subject(s)
Humans , Pest Control, Biological/statistics & numerical data , Pest Control, Biological/instrumentation , Pest Control, Biological/methodsABSTRACT
El control biológico de vectores en la agricultura ha dado magníficos resultados en muchos países incluyendo Colombia. El sistema de control de vectores de enfermedades humanas está en desarrollo en la China y Tailandia con el empleo de peces, y en otros países se emplea en forma creciente los bacilos esporulados como el B. sphaericus y B. thruringiasis. La Corporación para las Investigaciones Biológicas (CIB) ha logrado investigar en el programa de inventario un buen número de patógenos y de depredadores vertebrados e invertebrados que pueden llegar a ser de utilidad en el control de mosquitos. Se ha iniciado la evaluación de algunos de ellos