Search PubMed⌕ Search

Biomedical subjects

R Chuit

Publications and source records attributed to R Chuit.

28 records · Page 2Linked to original sources
PubMed1992

Result of a first step toward community-based surveillance of transmission of Chagas' disease with appropriate technology in rural areas.

The objective of this work was to develop an effective methodology for the surveillance of Chagas' disease vectors in rural areas. It was based on the use of sensor boxes and portable mini-pumps to be integrated into the regular health promotion activities of the Primary Health Care (PHC) agents. The proposed methodology involves a continuous passive intradomiciliary detection of triatomines by sensor boxes that are monitored quarterly by PHC agents. Insecticidal treatment of the houses was performed immediately after the detection of triatomines. The more conventional method of vertical surveillance involves a direct entomologic evaluation conducted by trained professionals. The entire house is searched and there is a mandated treatment of the positive houses. The results of the followups obtained in the county of Rio Hondo in Santiago del Estero Province during a 36-month evaluation period immediately following attack phase application of insecticides were analyzed. The initial high domiciliary and peridomiciliary infestations decreased abruptly after the insecticidal treatment in both areas. When the performances of both types of surveillance were compared, the PHC agent method showed a lower percentage of houses reinfested, with fewer triatomines in the former, and a decrease in their rate of Trypanosoma cruzi infection. Evaluations of reinfestations using the man/hour method and the senor box method showed the same sensitivity. A higher sensitivity for detection of low densities of vector populations was achieved using the sensor boxes. The cost of PHC agent/sensor boxes surveillance was five times lower than the classic one. The proposed strategy for the continuous surveillance of Chagas' disease vectors has demonstrated effectiveness, allows community participation, and seems suitable for large scale application.

Animals↗
PubMed1991

The status of transmission of Trypanosoma cruzi in an endemic area of Argentina prior to control attempts, 1985.

A field survey of transmission of Trypanosoma cruzi was carried out in an area which had never been sprayed with insecticide. A population census, mapping and house classification, examination of insects in houses, and a human serological survey were performed. The entomological examination showed that 97% of the houses (433/445) were infested by Triatoma infestans and that 31% of the bugs examined were infected with T. cruzi. The level of infection, as well as the number of insects captured, had no apparent relationship with the type of house. Trypanosoma cruzi was found in 30% of the human population, and in 10% of children up to four years old. The rates of infection were significantly lower for inhabitants, especially children, living in 'urban' houses. The prevalence rate for the children did not correlate with the number of insects collected in the houses. The improvement of houses, outside the framework of an integrated control programme, had no obvious impact on the level of transmission. Nevertheless, the replacement of the original houses by houses with plastered walls and roofs of metal or cement resulted in a decrease in the prevalence of infection in children younger than four years of age. The community showed little confidence in sanitary precautions against Chagas' disease prior to the start of the survey.

Age Factors↗
PubMedDate not supplied

Chagas disease in north-west Argentina: risk of domestic reinfestation by Triatoma infestans after a single community-wide application of deltamethrin.

The risk of domestic reinfestation by Triatoma infestans after a single community-wide application of delta-methrin (2.5% suspension concentrate at 25 mg active ingredient/m2) was studied in Amamá, north-west Argentina, where no insecticide spraying had been done by official control services. The percentage of infested houses fell from 88% before spraying in 1985 to nil during the 6 months after spraying, and thereafter increased from 5% in 1986 to 96% before a second treatment in 1992, fitting closely to a logistic model (r2 = 0.997). Significant risk factors associated with domestic reinfestation determined from stepwise logistic regression and one-factor analysis were the density of T. infestans in bedrooms just before spraying and the surface structure of indoor walls. Peak densities of bugs in 1988-1989 significantly differed between levels of both risk factors. Our study suggests the existence of stable determinants of infestation linked to the household which, in the absence of effective control measures, would also determine the speed of house recolonization and the ensuing bug densities. Plastering of mud walls before application of insecticides to all domestic and peridomestic structures is supported by the study.

Animals↗
PubMedDate not supplied

Usefulness of serology for the evaluation of Trypanosoma cruzi transmission in endemic areas of Chagas' disease.

Thirteen communities from 7 Argentinian provinces were selected for the evaluation of serology as an indicator of transmission of Chagas disease. Of the communities appraised, 6 did not have a history of previous treatment with insecticides and 7 had received sporadic or continuous insecticide treatment. The inhabitants of 20% of the houses of each locality were studied by serology. The samples were obtained by finger pricking and 50 microliters of blood were mixed with 15 microliter of 50% glycerine solution in tissue culture media to be assayed by Indirect Hemagglutination and Indirect Immunofluorescence tests. In untreated areas, the prevalence of infection in infants 0-4 years old was 17.5%, reaching to over 22% for the 5-9 year old group, and to 33.3% in 10-14 year old individuals. The prevalence in treated and surveyed areas was 2.6% in 0-4 year old children, 5.4% in 5-9 year old and 6.2% in 10-14 year old youngsters. The differences between both areas were statistically significant (p less than 0.005). This study favors serology as a valid indicator for the evaluation of transmission of Chagas disease in rural areas.

Adolescent↗