title: [Overview of the epidemiology of Chagas' disease in Chile].
abstract: Chile is a long and narrow country located in the south western coast of South America. Chagas' disease exists in the seven first (18 degrees 30'-34 degrees 36' South lat.) of the total of thirteen administrative regions of the country. In the 1982-1990 period a series of studies considering different epidemiological aspects of this parasitic zoonosis has been carried out with the following results: 5,601 rural of periurban dwellings were surveyed for the presence of Triatoma infestans (the most important and almost exclusive vector of Trypanosoma cruzi in Chile). 37.4% of the dwellings were infested according to the inhabitants and 29.4% were found infested according to the presence of tracks or insects captured. In 659 (17.2%) out of 3,822 T. infestans captured and examined T. cruzi was found in their abdominal contents. The most common sources of T. infestans feeding were mammals (89.0%), including man, and birds (9.5%). An indirect hemagglutination test (IHAT) for Chagas' disease, a very sensitive and specific reaction, was performed to 5,050 domestic mammals, resulting positive 7.9% of cats, 7.0% of dogs, 7.0% of goats, 4.9% of sheep and 4.1% of rabbits. 2,579 (16.9%) out of 15,418 persons were positive for the IAHT for Chagas' disease. The rates of infection were rather similar in males (17.5%) and females (16.2%) with an increase in infection rates in accordance with increase of age of individuals. The overall frequency of ECG abnormalities in positive IHAT persons was 18.7% against 8.8% in those with negative IHAT, whereas ECG abnormalities considered as suggestive of a chagasic etiology were 6.8% and 2.2% respectively. The esophageal motility in 311 persons with a positive IHAT and in 150 with a negative IHAT was found altered in 42.8% and 18.7% respectively. In the corresponding urban sectors of the 7 regions mentioned 2.7% of blood donors, 2.3% of delivering mothers, 2.6% of newborns and 0.6% of school children had positive IHAT. 646 chagasic women and 709 non-chagasic women in their reproductive span of life, and the products of the pregnancies that they had in a 6-year period were followed-up. No significant differences were found neither in the number nor in the evolution of pregnancies in both groups of mothers. Xenodiagnosis of children from chagasic mothers resulted positive in 6.3-8.9%, showing the transmission of T. cruzi by the placental route. Recently, 3 cases of congenital Chagas' disease of second generation have been demonstrated.(ABSTRACT TRUNCATED AT 400 WORDS)
authors.affiliation: Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad de Chile, Santiago.
authors.forename: H
authors.initials: H
authors.lastname: Schenone
authors.forename: M C
authors.initials: MC
authors.lastname: Contreras
authors.forename: J M
authors.initials: JM
authors.lastname: Borgoño
authors.forename: R
authors.initials: R
authors.lastname: Maturana
authors.forename: P
authors.initials: P
authors.lastname: Salínas
authors.forename: L
authors.initials: L
authors.lastname: Sandoval
authors.forename: A
authors.initials: A
authors.lastname: Rojas
authors.forename: P
authors.initials: P
authors.lastname: Tello
authors.forename: F
authors.initials: F
authors.lastname: Villarroel
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D014355:Chagas Disease / Q000453:epidemiology* / Q000209:etiology / Q000635:transmission; D002648:Child; D002675:Child, Preschool; D002677:Chile / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged
vernacular_title: Panorama general de la epidemiología de la enfermedad de Chagas en Chile.