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In order to investigate the prevalence of chagasic heart disease in Brazil, a national electrocardiographic survey was carried out from 1977 to 1981. A total of 5,347 electrocardiograms (ECG) were performed and paired by age and gender. The results obtained in relation with the autochthonous cases, were distributed by Brazilian states, as follows: Rio Grande do Sul (1,078), Minas Gerais (760), Bahia (612), Paraná (400), Paraiba (340), Piauí (218), Sergipe (216), Goiás (176), Pernambuco (170), Ceará (136) and Alagoas 134. The higher proportions of altered ECGs among seropositive individuals were found in the States of Goiás (63.6%), Minas Gerais (57.6%), Ceará (57.3%), Paraná (54.5%), Piauí (53.2%) and Paraiba (52.3%). Among the control individuals, these proportions were respectively 25%, 25.7%, 25%, 12.5%, 22.9% and 26.5%. A significant statistical difference of altered ECGs between positive and negative individuals was verified in all the States, with a single exception (Alagoas). The estimation of the gradient showed to be higher in Paraná State (42%), followed by Goiás (38.6%), Ceará (32.3%), Minas Gerais (31.9%), Piauí (30.3%), Paraíba (25.8%), Pernambuco (22.3%), Bahia (18.9%), Sergipe (16.7%), Rio Grande do Sul (9.9%) and Alagoas (7.5%). Concerning the distribution of the electrocardiographical alterations found in the eleven states, the main alterations find among the seropositive group were: ventricular extrasystoles, complete right bundle branch block, left anterior fascicular block, the association of complete right bundle branch block with left anterior fascicular block and primary alterations of the ST segment and of the T wave. Furthermore, these ECG alterations were more prevalent in the group of infected individuals.

Entomological surveillance of Chagas disease in Mambaí and Buritinópolis, in the State of Goiás, Brazil, has been kept up through the local population's participation, consisting of reporting the presence of vectors inside their homes. A long time has elapsed since instituting these control measures and it has now been certified that vector transmission has been halted. Thus, this study sought to evaluate the population's knowledge and practices in this situation. The results show that there has been progressive indifference towards the topic of 'Chagas disease', which can be attributed to the reduction in the magnitude of the problem that this disease represented, little participation in surveillance among schools, low epidemiological importance of secondary and native vectors and, consequently, limited control interventions from health services in response to notifications. It is proposed that direct search activities by means of sampling should be carried out periodically, and that there should be greater involvement among teaching institutions.

From January to March 2001 a seroepidemiological survey for American trypanosomiasis (Chagas disease) was carried out among urban and rural human populations in areas of the Upper Purus basin, in the western Brazilian Amazon region, using serial testing with three different serological techniques. The sample was composed of 1,055 individuals: 844 from urban and 211 from rural areas. Autochthonous infection was identified in nine individuals aged 16 to 72 years: five from urban and four from rural areas. The estimated prevalences of Chagas infection for the urban and rural areas were 0.6% (95% CI: 0.2-1.4) and 1.9% (95% CI: 0.6-4.5) respectively. An apparent clustering trend was noted: seven were born along the Purus river: three lived at the same locality and two of them in the same dwelling.

This work describes radiography studies of the esophagus in chagasic patients of the Mambaí project over a 25 year period. Each person realized two radiographs in four different periods (1975-1976, 1980-1982, 1988-1991 and 1998-2000). The first radiograph was realized in the right anterior oblique position after swallowing 75 ml of barium sulphate solution and another 60 seconds later. In all periods the same methodology was used. The radiographs were read by the same researcher, and the megaesophagus was classified in four groups according to Rezende and colleagues. The prevalence of megaesophagus was 5.2%; 5.0%; 18.6% and 13.9% in 1975-1976, 1980-1982, 1988-1991 and 1998-2000 respectively. The incidence of megaesophagus from 1975 to 2000 was 11.5% (51/445). During 25 year, 394 (84.2%) patients presented radiographs normal of esophagus, 11 (2.3%) diagnosed as megaesophagus in 1975-1976 did not progress, 61 (13%) that were normal, doubtful or already presented megaesophagus in 1975-1976, progressed and 2 (0.4%) presented regression of group I megaesophagus, diagnosed in previous studies.

A retrospective study was performed in a field clinic to characterize the clinical findings of tegumentary leishmaniasis in children from 0 to 5 years old. The clinical records of 4,464 patients were analyzed at the Primary Health Center of Corte de Pedra, Presidente Tancredo Neves, Bahia, Brazil, from May 1987 to December 1995. Four hundred and ninety one (11.8%) children were identified among 4,275 new cases of tegumentary leishmaniasis registered at this Unit. The gender ratio (M:F) for children under six years was 1.1:1. Cutaneous lesions predominated (98%), mainly skin ulcers (99%) located above the waist (p<0.05). Thirty five percent had multiple lesions. The observed magnitude of the disease in children, the similar proportion of cases in both genders and the location of the lesions suggest the possibility of peri or intradomiciliary transmission.

With the purpose of identifying risk factors for cutaneous leishmaniasis transmission in children from 0 to 5 years, a matched case-control study was carried out in Corte de Pedra, Bahia, Brazil, an endemic area of Leishmania (Viannia) braziliensis. Children with a positive leishmanin skin test and one or more active lesions or scars consistent with cutaneous leishmaniasis were defined as cases. Forty cases and 71 controls were selected and matched by age and place of residence. The presence of a family member with a history of cutaneous leishmaniasis in the year prior to the appearance of the disease in the child was found to be an important risk factor (MORMH = 17.75; 95%CI: 4.08-77.25). No evidence of association between the disease and other risk factors was found, such as child's habits inside or outside the house, domiciliary or peridomiciliary characteristics, or presence of vectors or probable reservoir animals. These findings support the hypothesis that humans serve as both the reservoir and source of infection for this age group.

The antibody response against Leishmania (Leishmania) amazonensis crude antigen was measured through the indirect immunofluorescent assay (IFA) and the immunoenzymatic assay (ELISA) in 114 patients with cutaneous leishmaniasis (CL) in Brazil. Fifty-four patients were infected by Leishmania (Viannia) braziliensis, and 60 patients had L. (V.) guyanensis infection. Patients were comparable by age, sex, disease duration and the Montenegro skin test diameter. L. (V.) braziliensis-infected patients showed significant lower number of ulcerated lesions, greater ulcerated area and higher proportion of lymph node enlargement. Sensitivity of IFA was 79.6% (95% CI 66.1-88.9) and 71.7% (95% CI 58.4-82.2) for L. (V.) braziliensis and L. (V.) guyanensis-infected patients, respectively (P=0.324). Sensitivity of ELISA was 98.2% (95% CI 88.8-99.9) and 85.0% (95% CI 72.9-92.5) for L. (V.) braziliensis and L. (V.) guyanensis-infected patients, respectively (P=0.018). Significant differences were observed in the magnitude of the antibody response before treatment with higher levels detected in L. (V.) braziliensis-infected patients by both serologic techniques. Eighty-four patients had serologic evaluations before and 12 weeks after treatment with meglumine antimoniate, 20 mg/kg/day for 20 days. Significant lower optic density values were observed after treatment with both species independent of cure or failure. Our data showed that L. (V.) braziliensis induces a higher antibody response against L. (L.) amazonensis antigens than L. (V.) guyanensis and that down-modulation of the antibody response occurs shortly during disease evolution after treatment. Moreover the data support the use of ELISA as a better tool for detection of antibodies in CL.

During 13 years, 190 individuals with chagasic infection were submitted to clinical and parasitological examinations to investigate the relationship between parasitemia and the evolution of chronic chagasic infection. Fifty-six patients with positive xenodiagnosis and 134 with negative exams were compared from 1988 to 91, it was found that 22 (39.3%) and 50 (37.3%), respectively, presented disease progression. The parasitemia was stratified into high, medium and low and the relation with the disease evolution showed that 5 (62.5%), 10 (41.7%) and 57 (36.1%), respectively, presented progressive disease, though without a statistically significant difference (p>0.05). When 20 patients with persistent parasitemia in 1976/91, were compared with 59 with negative xenodiagnosis, a progressive evolution was observed in 6 (30%) and 17 (28.8%), respectively. Comparing six patients with high parasitemia and 59 with negative exams, it was verified that 3 (50%) and 17 (28.8%), respectively, showed progressive disease, but this was not statistically significant, (p>0.05). Mean age with high, medium and low parasitemia were 39.6, 45.3 and 41.5 years, respectively, (p>0.05). Mean age in patients showing progressive, unaltered and regressive evolution was 46.4, 39.8 and 32.6 years, respectively, with a statistically significant difference between progressive and regressive evolution (p<0.05). It is suggested that high parasitemia did not have an influence on the evolution of the chronic infection.

We analyzed data from historical controls treated with meglumine antimoniate to compare the frequency of adverse events observed in patients with cutaneous leishmaniasis treated with the same dose of meglumine antimoniate contaminated with heavy metals in an endemic area of the State of Bahia, Brazil. Group A patients were treated in 2000 with the drug produced by Eurofarma Laborat rios Ltda., S o Paulo, Brazil (lot A) and group B patients were treated in 1996 with the reference drug produced by Rhodia Farma Ltda., S o Paulo, Brazil (lot B). We observed an unusual higher frequency of skin reactions in group A patients. However, all type of adverse events observed in group A were also observed in group B. The physico-chemical analysis of these lots revealed that lot A had lower pH and higher concentration of total and trivalent antimony, lead, cadmium, and arsenic. Our findings suggest that the skin reactions could be attributed to heavy metal contamination of lot A.

In 1999, we performed serological and entomological surveys to evaluate the impact of vectorial control measures against transmission of Chagas' disease in the endemic area of Mambaí and Buritinópolis (GO). A census was undertaken of the population, after which the entomological survey was performed regarding the dwelling units and serological evaluation of the human population. Blood samples were collected by digital puncture in filter paper. The first serologic test performed to detect antibodies against Trypanosoma cruzi was the indirect immunofluorescence test (IFI) with (1/2)0 positive dilution as cut-off point and, positive samples were further evaluated with indirect hemagglutination reaction (HAI). The prevalence of positive IFI reactions was 12.3% (95%CL: 11.5-13.2). Triatoma infestans was not found within the dwellings. The absence of infection among individuals younger than 14 years and, the absence of T. infestans during the last entomological survey demonstrates the success of the control program of Chagas' disease in the studied area where the vectorial transmission can be considered to have been interrupted.

In a prospective study to evaluate the influence of secondary bacterial infection on the evaluation of cutaneous leishmaniasis, in Corte de Pedra (Bahia), we isolated Corynebacterium diphtheriae in 7 (8.3%) out of 84 patients with ulcers studied. Due to the small number of patients with the presence of the bacteria in the ulcer, we could not conclude whether Corynebacterium diphtheriae behaves only as a colonizer nor its influence on the healing of the leishmaniotic ulcer.

Eighty Leishmania isolates from patients who contracted cutaneous leishmaniasis in the Manaus region, Amazonas State, Brazil, were identified as Leishmania (Viannia) guyanensis by the electrophoretic profiles of six enzymes. None reacted with the species-specific monoclonal antibody B19. Two L. (V.) guyanensis subpopulations were detected with the monoclonals B2 and B12. The lack of B19 expression by the L. (V.) guyanensis strains in the present study contrasts with that of the vast majority of the strains of the same parasite from eastern Amazonia and French Guyana that express the epitope.