Metallothionein-1 and nitric oxide expression are inversely correlated in a murine model of Chagas disease

Chagas disease, caused by Trypanosoma cruzi, represents an endemic among Latin America countries. The participation of free radicals, especially nitric oxide (NO), has been demonstrated in the pathophysiology of seropositive individuals with T. cruzi. In Chagas disease, increased NO contributes to the development of cardiomyopathy and megacolon. Metallothioneins (MTs) are efficient free radicals scavengers of NO in vitro and in vivo. Here, we developed a murine model of the chronic phase of Chagas disease using endemic T. cruzi RyCH1 in BALB/c mice, which were divided into four groups: infected non-treated (Inf), infected N-monomethyl-L-arginine treated (Inf L-NAME), non-infected L-NAME treated and non-infected vehicle-treated. We determined blood parasitaemia and NO levels, the extent of parasite nests in tissues and liver MT-I expression levels. It was observed that NO levels were increasing in Inf mice in a time-dependent manner. Inf L-NAME mice had fewer T. cruzi nests in cardiac and skeletal muscle with decreased blood NO levels at day 135 post infection. This affect was negatively correlated with an increase of MT-I expression (r = -0.8462, p < 0.0001). In conclusion, we determined that in Chagas disease, an unknown inhibitory mechanism reduces MT-I expression, allowing augmented NO levels.     

Behavioural alterations are independent of sickness behaviour in chronic experimental Chagas disease

The existence of the nervous form of Chagas disease is a matter of discussion since Carlos Chagas described neurological disorders, learning and behavioural alterations in Trypanosoma cruzi-infected individuals. In most patients, the clinical manifestations of the acute phase, including neurological abnormalities, resolve spontaneously without apparent consequence in the chronic phase of infection. However, chronic Chagas disease patients have behavioural changes such as psychomotor alterations, attention and memory deficits, and depression. In the present study, we tested whether or not behavioural alterations are reproducible in experimental models. We show that C57BL/6 mice chronically infected with the Colombian strain of T. cruzi (150 days post-infection) exhibit behavioural changes as (i) depression in the tail suspension and forced swim tests, (ii) anxiety analysed by elevated plus maze and open field test sand and (iii) motor coordination in the rotarod test. These alterations are neither associated with neuromuscular disorders assessed by the grip strength test nor with sickness behaviour analysed by temperature variation sand weight loss. Therefore, chronically T. cruzi-infected mice replicate behavioural alterations (depression and anxiety) detected in Chagas disease patients opening an opportunity to study the interconnection and the physiopathology of these two biological processes in an infectious scenario.     

Discovery and characterization of an antibody, anti-egressin, that is able to inhibit Trypanosoma cruzi egress in vitro

Trypanosoma cruzi, a protozoan parasite, is the etiologic agent of Chagas disease. The disease is characterized by acute and chronic phases, with high and low parasitemia, respectively. A strong immune activation is necessary for the host to enter the chronic phase; however, immune mechanisms participating in the reduction of parasites between the acute and chronic phases of the disease have been very difficult to elucidate. We report here the discovery of anti-egressin, an antibody present in serum from chronically infected BALB/c mice that is able to inhibit parasite egress from infected BALB/c fibroblast cultures in vitro. The antibody is very concentrated in serum from these mice; chronic serum may be diluted 1:20 while still maintaining functional activity. Isotype analysis of anti-egressin has suggested it to be IgG2a. Further analysis revealed that anti-egressin was specific for a component expressed on the surface of infected host cells. The specificity of anti-egressin toward the extracellular portion of infected host cells was demonstrated both by using a quantitative assay measuring released trypomastigotes and through immunocytochemical staining. The novel role of anti-egressin in the inhibition of parasite egress from infected host cells has not been described in the literature to date. We believe that anti-egressin plays an important role in achieving the low parasitemia characteristic of chronic Chagas disease.     

Antiegressin acts late in the intracellular growth cycle of Trypanosoma cruzi to inhibit parasite egress

Trypanosoma cruzi is the causative agent of Chagas disease, which is characterized by acute and chronic phases. During the former, parasitemia rises dramatically, then decreases significantly during the chronic phase. Immune mechanisms responsible for the parasitemia reduction have not been thoroughly elucidated. The goal of the present study was to further characterize the immune response during chronic infection. Previously, we described antiegressin, an antibody in sera from chronically infected mice. The in vitro presence of antiegressin inhibits parasite egress from infected host cells. Antiegressin appears by day 14 of an in vivo infection and is maintained through at least day 280 postinfection. The in vitro functional activity of antiegressin is initiated late in the 4-6 days intracellular growth cycle of T. cruzi; antiegressin may be added at day 4, inhibiting parasite release at day 5. Immunocytochemical staining using antineuraminidase demonstrates the presence of mature parasites inside host BALB/c fibroblasts grown in the presence of antiegressin. These results demonstrate the ability of antiegressin to inhibit emergence of developmentally mature trypomastigotes from infected host cells late in their intracellular growth cycle. We believe this antibody plays an important and novel role in achieving the low-parasitemia characteristic of chronic Chagas disease.     

Heritable integration of kDNA minicircle sequences from Trypanosoma cruzi into the avian genome: insights into human Chagas disease

We demonstrate the genetic transfer of DNA between eukaryotes from different kingdoms. The mitochondrial kinetoplast DNA (kDNA) of the intracellular parasite Trypanosoma cruzi is transferred to human patients with Chagas disease. This transfer was reproduced experimentally in rabbits and chickens. The kDNA is integrated into the host genome. In the human chromosomes, five loci were identified as integration sites, and the beta-globin locus and LINE-1 retrotransposons were frequently targeted. Short repeated sequences in the parasite and the target host DNAs favor kDNA integration by homologous recombination. Introduced kDNA was present in offspring of chronically infected rabbits and in chickens hatched from T. cruzi-inoculated eggs. kDNA incorporated into the chicken germline was inherited through the F2 generation in the absence of persistent infection. kDNA integration represents a potential cause for the autoimmune response that develops in a percentage of chronic Chagas patients, which can now be approached experimentally.     

Severity of chronic experimental Chagas' heart disease parallels tumour necrosis factor and nitric oxide levels in the serum: models of mild and severe disease

Heart tissue inflammation, progressive fibrosis and electrocardiographic alterations occur in approximately 30% of patients infected by Trypanosoma cruzi, 10-30 years after infection. Further, plasma levels of tumour necrosis factor (TNF) and nitric oxide (NO) are associated with the degree of heart dysfunction in chronic chagasic cardiomyopathy (CCC). Thus, our aim was to establish experimental models that mimic a range of parasitological, pathological and cardiac alterations described in patients with chronic Chagas’ heart disease and evaluate whether heart disease severity was associated with increased TNF and NO levels in the serum. Our results show that C3H/He mice chronically infected with the Colombian T. cruzi strain have more severe cardiac parasitism and inflammation than C57BL/6 mice. In addition, connexin 43 disorganisation and fibronectin deposition in the heart tissue, increased levels of creatine kinase cardiac MB isoenzyme activity in the serum and more severe electrical abnormalities were observed in T. cruzi-infected C3H/He mice compared to C57BL/6 mice. Therefore, T. cruzi-infected C3H/He and C57BL/6 mice represent severe and mild models of CCC, respectively. Moreover, the CCC severity paralleled the TNF and NO levels in the serum. Therefore, these models are appropriate for studying the pathophysiology and biomarkers of CCC progression, as well as for testing therapeutic agents for patients with Chagas’ heart disease.     

Increased oxidative stress is correlated with mitochondrial dysfunction in chagasic patients

Previously, we have shown in an experimental model of Trypanosoma cruzi infection that increased oxidative stress and antioxidant insufficiency are associated with myocardial (cellular and mitochondrial) oxidative damage and mitochondrial functional decline and might be of pathological significance in Chagas disease. In the present study, we investigated whether enhanced oxidative stress and mitochondrial functional decline are found in human chagasic patients. Our data show substantially higher plasma (two-four-fold) and mitochondrial (67%) malonylaldehyde (MDA) levels in chagasic (n = 80, group 2) compared to healthy (n = 50, group 1) subjects. Moreover, antioxidant defense was compromised in chagasic patients. Hence, we noted a 50% decline in glutathione content and losses of 31, 60, and 68% in glutathione peroxidase, superoxide dismutase (SOD), and MnSOD activities, respectively, relative to the findings in healthy controls. Further, chagasic subjects exhibited decreased mitochondrial respiratory complex (CI: 72%; CIII: 71%) activities. Nonchagasic cardiomyopathy subjects (n = 20, group 3) exhibited marginally higher plasma MDA levels compared to gp1 subjects and were not compromised in plasma antioxidant defense capacity. These data suggest that human chagasic patients sustain an antioxidant/oxidant imbalance and a mitochondrial decline of respiratory complex activities in the circulatory system. A positive correlation between increased MDA levels, MnSOD decline, and inhibition of respiratory complexes suggests that oxidative stress may contribute to mitochondrial dysfunction in chagasic patients.     

Erythrocyte Oxidant/Antioxidant Status in Essential Hyperhidrosis

Essential Hyperhidrosis is a disorder of excessive, bilateral, and relatively symmetric sweating occurring in the axillae, palms, soles, or craniofacial region without obvious etiology. Nitric oxide may play a physiological part in the production and/or excretion of sweat in skin eccrine glands. Tempol, a SOD mimetic, increases the half-life of NO and results in vasodilatation, hypotension, and reflex activation of sympathetic nervous system. Reactive oxygen species (ROS) may directly activate both central and peripheral sympathetic nervous system activity. We assessed the levels of malondialdehyde (MDA), the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) of red blood cells in patients with essential hyperhidrosis (n = 31) compared to age-and sex-matched healthy controls (n = 28). Erythrocyte activities of SOD and level of MDA were detected significantly higher (p = 0.020, p = 0.004 and respectively) and activities of CAT and GSH-Px were significantly lower (p = 0.0001, p = 0.0001 respectively) in patients than controls. Our results support the hypothesis that oxidative damage resulting from increased ROS production along with insufficient capacity of antioxidant mechanisms may be involved in pathogenesis of EH.     

Erythrocyte antioxidant activity and trace element levels in Behçet’s disease

Selenium (Se), zinc (Zn), copper (Cu), and antioxidant enzyme (superoxide dismutase [SOD] and glutathione peroxidase [GSH-Px]) levels in sera were detected in Behçet patients. Age and sex matched controls were used to find out if oxidative stress takes place in the etiopathogenesis of Behçet’s disease. Superoxide dismutase levels were found to be lower in the whole patients group when compared to controls. In whole patients and inactive patients’ group Zn and Se levels were found to be higher, but not different in the active patients group when compared to controls. No significant difference was found between the groups as Cu and glutathione peroxidase levels were taken into consideration. According to the results of the present study, SOD level is low in Behçet’s disease patients’ sera independent from the phase of the disease, and as a result of decreased SOD activity, increased production of free oxygen radicals may play a role in the etiopathogenesis of the disease.     

Effects of mammal host diversity and density on the infection level of Trypanosoma cruzi in sylvatic kissing bugs

Several reports have described host species diversity and identity as the most important factors influencing disease risk, producing either dilution or amplification of the pathogen in a host community. Triatomine vectors, mammals and the protozoan Trypanosoma cruzi (Trypanosomatida: Trypanosomatidae) Chagas are involved in the wild cycle of Chagas disease, in which infection of mammals occurs by contamination of mucous membranes or skin abrasions with insect‐infected faeces. We examined the extent to which host diversity and identity determine the infection level observed in vector populations (i.e. disease risk in humans). We recorded infection in triatomine colonies and on the coexisting host mammalian species in semi‐arid Chile. Host diversity, and total and infected host species densities are used as predictor variables for disease risk. Disease risk did not correlate with host diversity changes. However, the densities of each infected rodent species were positively associated with disease risk. We suggest that the infected host density surrounding the vector colonies is a relevant variable for disease risk and should be considered to understand disease dynamics. It is crucial to pay attention on the spatial scale of analysis, considering the pattern of vector dispersal, when the relationship between host diversity and disease risk is studied.     

mRNA expression of antioxidant enzymes (SOD, CAT and GSH-Px) and lipid peroxidative stress in liver of Atlantic salmon (Salmo salar) exposed to hyperoxic water during smoltification

The mRNA levels of three antioxidant genes, Cu/Zn superoxide dismutase (SOD), catalase (CAT) and phospholipid hydroperoxide glutathione peroxidase (GSH-Px), were quantified with real-time qRT-PCR in liver of Atlantic salmon Salmo salar exposed to 80% (normoxia), 105% and 130% O2 saturation for 54 days. The salmon were then translocated and exposed to 90% and 130% O2 saturation for additional 72 days during smoltification. TBARS and vitamin E levels in liver and the levels of oxidized glutathione (GSSG), total glutathione (GSH) and the resulting oxidative stress index (OSI) in blood were quantified as traditional oxidative stress markers. No significant mean normalized expression (MNE) differences of SOD, CAT or GSH-Px were found in liver after hyperoxia exposure at the two sampling times. Significantly decreased OSI was found in smolt exposed to 130% O2 saturation after 126 days (n = 18, P < 0.0001), indicating hyperoxia-induced oxidative stress. No effects were seen on growth, or on the levels of thiobarbituric reactive substances (TBARS) and vitamin E in liver after the exposure experiment. Overall, the mRNA expression of SOD, CAT and GSH-Px in liver related poorly with the hyperoxic exposure regimes, and more knowledge are needed before the expressed levels of these antioxidant genes can be applied as biomarkers of hyperoxia in Atlantic salmon.     

Anti-oxidant activity of superoxide dismutase and glutathione peroxidase enzymes in skeletal muscles from slaughter cattle infected with Taenia saginata

It is known that highly reactive oxygene species produced during normal cellular metabolism represent a powerful effector mechanism against parasites. Superoxide dismutase (SOD) and glutathione peroxidase (GPx) belong to the main defense anti-oxidants that prevent the formation of new free radical species. The aim of this study was to assess the activities of SOD and GPx in cattle tissues infected with Taenia saginata. We observed a statistically significant increase in the SOD and GPx activities (p = 0.00003, 0.00008, respectively, Student’s t-test) in skeletal muscles infected with T. saginata in spectrophotometric analysis. With the use of western blot technique, SOD synthesis stimulation has appeared in the host tissues containing cysticerci in contrast with the control samples. There was no statistically significant increase in the GPx band intensity observed in the studied samples in comparison to controls (Gene Tools Version 4.01 program). These results support the significance of anti-oxidant processes in host defense mechanism during parasitic infections.     

Aspirin treatment of mice infected with Trypanosoma cruzi and implications for the pathogenesis of Chagas disease

Chagas disease, caused by infection with Trypanosoma cruzi, is an important cause of cardiovascular disease. It is increasingly clear that parasite-derived prostaglandins potently modulate host response and disease progression. Here, we report that treatment of experimental T. cruzi infection (Brazil strain) beginning 5 days post infection (dpi) with aspirin (ASA) increased mortality (2-fold) and parasitemia (12-fold). However, there were no differences regarding histopathology or cardiac structure or function. Delayed treatment with ASA (20 mg/kg) beginning 60 dpi did not increase parasitemia or mortality but improved ejection fraction. ASA treatment diminished the profile of parasite- and host-derived circulating prostaglandins in infected mice. To distinguish the effects of ASA on the parasite and host bio-synthetic pathways we infected cyclooxygenase-1 (COX-1) null mice with the Brazil-strain of T. cruzi. Infected COX-1 null mice displayed a reduction in circulating levels of thromboxane (TX)A(2) and prostaglandin (PG)F(2α). Parasitemia was increased in COX-1 null mice compared with parasitemia and mortality in ASA-treated infected mice indicating the effects of ASA on mortality potentially had little to do with inhibition of prostaglandin metabolism. Expression of SOCS-2 was enhanced, and TRAF6 and TNFα reduced, in the spleens of infected ASA-treated mice. Ablation of the initial innate response to infection may cause the increased mortality in ASA-treated mice as the host likely succumbs more quickly without the initiation of the "cytokine storm" during acute infection. We conclude that ASA, through both COX inhibition and other "off-target" effects, modulates the progression of acute and chronic Chagas disease. Thus, eicosanoids present during acute infection may act as immunomodulators aiding the transition to and maintenance of the chronic phase of the disease. A deeper understanding of the mechanism of ASA action may provide clues to the differences between host response in the acute and chronic T. cruzi infection.     

Plasma values of oxidants and antioxidants in acute brain hemorrhage

The levels of oxidants xanthine oxidase (XO), nitric oxide (NO), and malondialdehyde (MDA) and of the antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and glutathione reductase (GRD) were determined in plasma within 24 h after onset of hemorrhagic stroke in 17 patients (9 men and 8 women, aged 60.7+/-11.5 yr) and in 20 healthy controls (12 men and 8 women, aged 62.5+/-8.3 yr). Compared to controls, the plasma SOD and total superoxide scavenger activities (TSSA) were significantly lower and the NO levels were significantly higher among the stroke patients. XO showed a slight, nonsignificant increase in the patients, but the levels of MDA, NSSA, GRD, and GSH-Px did not show any significant differences between the two groups. The hemorrhage volume was negatively correlated with the initial score of the Glasgow Coma Scale and a positive correlation with lethal outcome, but it did not correlate significantly with any of the measured parameters. The results suggest that free radicals might play a role in the development of brain injury following brain hemorrhage.     

Effect of overexpression of wild-type and mutant Cu/Zn-superoxide dismutases on oxidative damage and antioxidant defences: relevance to Down's syndrome and familial amyotrophic lateral sclerosis

Patients with Down's syndrome (DS) show elevated levels of copper, zinc-containing superoxide dismutase (SOD1) and appear to have increased lipid peroxidation and oxidative damage to DNA as well as elevated glutathione peroxidase activity. Increasing SOD1 levels by gene transfection in NT-2 and SK-N-MC cell lines also led to a rise in glutathione peroxidase activity, but this was nevertheless accompanied by decreased proliferation rates, increased lipid peroxidation and protein carbonyls, and a trend to a rise in 8-hydroxyguanine and protein-bound 3-nitrotyrosine. Transfection of these cell lines with DNA encoding two mutant SOD1 enzymes (G37R and G85R) associated with familial amyotrophic lateral sclerosis (FALS), produced similar, but more severe changes, i.e. even lower growth rates, higher lipid peroxidation, 3-nitrotyrosine and protein carbonyl levels, decreased GSH levels, raised GSSG levels and higher glutathione peroxidase activities. Since G85R has little SOD activity, these changes cannot be related to increased O(2)(-) scavenging. In no case was SOD2 (mitochondrial Mn-SOD) level altered. Our cellular systems reproduce many of the biochemical changes observed in patients with DS or ALS, and in transgenic mice overexpressing mutant SOD1. They also show the potentially deleterious effects of SOD1 overexpression on cellular proliferation, which may be relevant to abnormal development in DS.     

Protective effect of arginine on oxidative stress in transgenic sickle mouse models

Sickle cell disease (SCD) is characterized by reperfusion injury and chronic oxidative stress. Oxidative stress and hemolysis in SCD result in inactivation of nitric oxide (NO) and depleted arginine levels. We hypothesized that augmenting NO production by arginine supplementation will reduce oxidative stress in SCD. To this end, we measured the effect of arginine (5% in mouse chow) on NO metabolites (NOx), lipid peroxidation (LPO), and selected antioxidants in transgenic sickle mouse models. Untreated transgenic sickle (NY1DD) mice (expressing  75% β^S-globin of all β-globins; mild pathology) and knockout sickle (BERK) mice (expressing exclusively hemoglobin S; severe pathology) showed reduced NOx levels and significant increases in the liver LPO compared with C57BL mice, with BERK mice showing maximal LPO increase in accordance with the disease severity. This was accompanied by reduced activity of antioxidants (glutathione, total superoxide dismutase, catalase, and glutathione peroxidase). However, GSH levels in BERK were higher than in NY1DD mice, indicating a protective response to greater oxidative stress. Importantly, dietary arginine significantly increased NOx levels, reduced LPO, and increased antioxidants in both sickle mouse models. In contrast, nitro-L-arginine methylester, a potent nonselective NOS inhibitor, worsened the oxidative stress in NY1DD mice. Thus, the attenuating effect of arginine on oxidative stress in SCD mice suggests its potential application in the management of this disease.     

Pharmacokinetic and pharmacodynamic responses in adult patients with Chagas disease treated with a new formulation of benznidazole

Pharmacological treatment of Chagas disease with benznidazole (BNZ) is effective in children in all stages, but it is controversial in chronically infected adults. We report the pharmacokinetics and pharmacodynamics in six adult patients with Chagas disease treated with the new BNZ formulation (ABARAX^®) in doses between 2.5-5.5 mg/Kg/day. All but one patient had plasmatic BNZ concentrations within the expected range. All patients finalised treatment with nondetectable Trypanosoma cruziquantitative polymerase chain reaction, which remained nondetectable at the six month follow-up. Our data suggests parasitological responses with the new BNZ and supports the hypothesis that treatment protocols with lower BNZ doses may be effective.     

Oxidative damage during chagasic cardiomyopathy development: role of mitochondrial oxidant release and inefficient antioxidant defense

In this study, we evaluated the oxidant status and antioxidant defense capabilities of the heart during the course of Trypanosoma cruzi infection and disease development in a murine model system. Our data show that the extent of protein carbonylation and lipid peroxidation is increased in the heart, but not the skeletal muscle, of infected mice. The level of oxidative injury biomarkers in the myocardium consistently increased with chronic disease severity. The antioxidant defense constituted by catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GSR), and reduced glutathione was increased in murine heart and skeletal tissue in response to the stress of T. cruzi infection. After the initial burst, CAT, GPx, and GSR remained unresponsive to the severity of chronic tissue damage in chagasic hearts. The cardiac level of Mn(2+) superoxide dismutase (MnSOD) was diminished in chagasic mice. Our data suggest that the host responds to acute injuries by activating antioxidant defenses that are of sufficient magnitude to scavenge the reactive oxidants in skeletal tissue. The myocardia of infected mice, however, sustain increased oxidative injuries with disease progression. We surmise that MnSOD deficiencies, resulting in the increased release of mitochondrial free radicals, lead to sustained oxidative stress that exceeds the cardiac antioxidant defense capacity and contribute to persistent oxidative damage in chagasic myocardium.     

Evolution and pathology in chagas disease--a review

Trypanosoma cruzi acute infections often go unperceived, but one third of chronically infected individuals die of Chagas disease, showing diverse manifestations affecting the heart, intestines, and nervous systems. A common denominator of pathology in Chagas disease is the minimal rejection unit, whereby parasite-free target host cells are destroyed by immune system mononuclear effectors cells infiltrates. Another key feature stemming from T. cruzi infection is the integration of kDNA minicircles into the vertebrate host genome; horizontal transfer of the parasite DNA can undergo vertical transmission to the progeny of mammals and birds. kDNA integration-induced mutations can enter multiple loci in diverse chromosomes, generating new genes, pseudo genes and knock-outs, and resulting in genomic shuffling and remodeling over time. As a result of the juxtaposition of kDNA insertions with host open reading frames, novel chimeric products may be generated. Germ line transmission of kDNA-mutations determined the appearance of lesions in birds that are indistinguishable from those seen in Chagas disease patients. The production of tissue lesions showing typical minimal rejection units in birds' refractory to T. cruzi infection is consistent with the hypothesis that autoimmunity, likely triggered by integration-induced phenotypic alterations, plays a major role in the pathogenesis of Chagas disease.     

Burden of Chagas disease in Brazil, 1990–2016: findings from the Global Burden of Disease Study 2016

Chagas disease continues to be an important cause of morbidity, mortality and disability in several Latin American countries, including Brazil. Using findings from the Global Burden of Disease Study 2016 (GBD, 2016), we present years of life lost, years lived with disability, and disability-adjusted life years due to Chagas disease in Brazil, by sex, age group, and Brazilian states, from 1990 to 2016. Results are reported in absolute numbers and age-standardized rates (per 100,000 population) with 95% uncertainty intervals. In 2016, 141,640 disability-adjusted life years (95% uncertainty intervals: 129,065–155,941) due to Chagas disease were estimated in Brazil, with a relative reduction of 36.7% compared with 1990 (223,879 disability-adjusted life years (95% uncertainty intervals: 209,372–238,591)). Age-standardized disability-adjusted life year rates declined at the national level (?69.7%) and in all Brazilian states between 1990 and 2016, but with different regional patterns. The decrease in the disability-adjusted life year rates was driven primarily by a consistent reduction in the years of life lost rates, the main component of total disability-adjusted life years for Chagas disease. The highest fatal and non-fatal burden due to Chagas disease was observed among males, the elderly, and in those Brazilian states encompassing important endemic areas for vector transmission in the past. Despite the consistent reduction in its burden during the period, Chagas disease is still an important and neglected cause of health lost due to premature mortality and disability in Brazil. Efforts should be made to maintain the political interest and sustainability of surveillance and control actions for Chagas disease, prevent the risk of re-emergence of vector transmission in endemic areas, and provide health care to chronically infected individuals, including early diagnosis and treatment interventions.