Estudo soroepidemiológico da doença de chagas no município de Josenópolis, Norte de Minas Gerais

Abstract

The present study aims to determine the seroprevalence of Chagas disease (DCh) in children from 0 to 14 years old in the city of Josenópolis, North of Minas Gerais, and to evaluate aspects related to the controlling program of this endemic. The study was carried out in four phases. In the first phase, data were collected through a survey of the number of chagasic patients in the city using the territorialisation forms of Family Health Program (in Portuguese Programa Saúde da Família - PSF). 332 patients had the disease which corresponded to 7.7% of the overall number of those who receive medical care at the health services. In the second phase, a seroepidemiological survey was conducted to estimate the current rate of DCh transmission. At first, serological analysis was realized using blood samples collected in filter paper of 1,131 children (99,1% registered in PSF). The samples were examined by immunoenzyme assay (EIE). Then, the samples considered reactive and indeterminate were submitted to confirmatory serology in venous blood sample by the EIE, Indirect Hemagglutination (IHA), Indirect Immunofluorescence (IIF) and Recombinant Immunoenzyme Assay (EIE-rec). No sample was considered positive which confirmed the absence of the infection by T. cruzi in the sample and also a low recent transmission of Chagas disease in the city. In the third phase, vector data were collected from the statistics and information of the Program for the Control of Chagas Disease provided by the Regional Health Management of Montes Claros, from January 1997 to October 2013, as well as Entomological Surveillance Data of Josenópolis referring to triatomine collected by the population, from 2011 to 2012. Data showed a low insect density in the area and the presence of six triatomine species: T. pseudomaculata, T. vitticeps, P. geniculatus, T. sordida, P. megistus and T. melanocephala. Domiciliary triatomines represented 75.4% of the captured insects. Natural infection was observed in T. vitticeps and T. pseudomaculata. In the fourth phase, a descriptive exploratory study was carried out to establish the level of knowledge of health care professionals regarding the control of the disease and epidemiological surveillance methods. 80% of the respondents had never attended any training course and were not aware of control program practices. Among the main difficulties found it is important to highlight the lack of better training program for health professionals, unawareness of the population about the Control Program of Chagas Disease, lack of educational materials and precarious transportation service. In conclusion, we can state that no indication of ongoing active transmission and low rates of household vector infestation were observed. However, the presence of T. vitticeps (a typically wild triatomine species) in the domiciliary environment is of epidemiologic interest and have to be taken into account in the planning of surveillance measures, since there is evidence of domestic and wild cycles overlapping in the region. Continual monitoring work of the infestation, professional qualification and an improvement of standard of living should be considered to prevent the disease and its infection transmission as well. Empowering the population through education and convince them to participate in programs to control the disease are also strongly recommended.