Epidemiological and clinical profile of patients with Chagas disease in the Central-North area of Paraná, Southern Brazil

<div><p>Abstract INTRODUCTION Profiles of patients with Chagas disease in Paraná were studied. METHODS A descriptive, questionnaire-based study was performed. RESULTS Of 270 participants, 64% were female, 60% were aged ≥65 years, 91% were infected via vector transmission, and 44% were infected in Paraná. Indeterminate (30%), cardiac (36%), cardiodigestive (20%) and digestive (14%) forms were found. CONCLUSIONS: Patients who were older than 65 years of age, retired, female, living in the urban area of Maringá, and infected by vector transmission in childhood in Paraná presented cardiac and digestive signs and did not receive etiological treatment when first diagnosed.</p></div

Sympatry influence in the interaction of Trypanosoma cruzi with triatomine

<div><p>Abstract INTRODUCTION: Trypanosoma cruzi, the etiologic agent of Chagas disease, is widely distributed in nature, circulating between triatomine bugs and sylvatic mammals, and has large genetic diversity. Both the vector species and the genetic lineages of T. cruzi present a varied geographical distribution. This study aimed to verify the influence of sympatry in the interaction of T. cruzi with triatomines. Methods: The behavior of the strains PR2256 (T. cruzi II) and AM14 (T. cruzi IV) was studied in Triatoma sordida (TS) and Rhodnius robustus (RR). Eleven fifth-stage nymphs were fed by artificial xenodiagnosis with 5.6 × 103 blood trypomastigotes/0.1mL of each T. cruzi strain. Every 20 days, their excreta were examined for up to 100 days, and every 30 days, the intestinal content was examined for up to 120 days, by parasitological (fresh examination and differential count with Giemsa-stained smears) and molecular (PCR) methods. Rates of infectivity, metacyclogenesis and mortality, and mean number of parasites per insect and of excreted parasites were determined. RESULTS: Sympatric groups RR+AM14 and TS+PR2256 showed higher values of the four parameters, except for mortality rate, which was higher (27.3%) in the TS+AM14 group. General infectivity was 72.7%, which was mainly proven by PCR, showing the following decreasing order: RR+AM14 (100%), TS+PR2256 (81.8%), RR+PR2256 (72.7%) and TS+AM14 (36.4%). CONCLUSIONS: Our working hypothesis was confirmed once higher infectivity and vector capacity (flagellate production and elimination of infective metacyclic forms) were recorded in the groups that contained sympatric T. cruzi lineages and triatomine species.</p></div

Allocation of the <i>Trypanosoma cruzi</i> isolated in the State of Amazonas into known phylogenetic clusters, most recently classified as TcI to TcVI, based on cytochrome c oxidase subunit II gene sequencing.

<p>Allocation of the <i>Trypanosoma cruzi</i> isolated in the State of Amazonas into known phylogenetic clusters, most recently classified as TcI to TcVI, based on cytochrome c oxidase subunit II gene sequencing.</p

Geographic distribution and reservoirs of the haplotypes of the <i>Trypanosoma cruzi</i> isolated in the State of Amazonas, based on single-nucleotide polymorphisms identified by cytochrome c oxidase subunit II gene sequencing.

<p>Geographic distribution and reservoirs of the haplotypes of the <i>Trypanosoma cruzi</i> isolated in the State of Amazonas, based on single-nucleotide polymorphisms identified by cytochrome c oxidase subunit II gene sequencing.</p

Geographic distribution and reservoirs of the haplotypes of the <i>Trypanosoma cruzi</i> isolated in the State of Amazonas, based on single-nucleotide polymorphisms identified by glucose-phosphate isomerase gene sequencing.

<p>Geographic distribution and reservoirs of the haplotypes of the <i>Trypanosoma cruzi</i> isolated in the State of Amazonas, based on single-nucleotide polymorphisms identified by glucose-phosphate isomerase gene sequencing.</p

Mean values of biological parameters from <i>Trypanosoma cruzi</i> I and IV strains.

a<p>Number of trypomastigotes/0,1 mL of blood.</p>b<p>p<0.05: significant difference in the T-student test.</p

Number of mice infected with <i>Trypanosoma cruzi</i> I and IV strains presenting histopathological alterations.

<p>Number of mice infected with <i>Trypanosoma cruzi</i> I and IV strains presenting histopathological alterations.</p

Curves of mean parasitemia obtained from <i>Trypanosoma cruzi</i> I and IV strains.

<p>Curves of mean parasitemia obtained from <i>Trypanosoma cruzi</i> I and IV strains.</p

Geographic origin of the <i>Trypanosoma cruzi</i> strains from the State of Amazonas, Brazil.

<p>Geographic origin of the <i>Trypanosoma cruzi</i> strains from the State of Amazonas, Brazil.</p

Virulence parameters obtained in Swiss mice from <i>Trypanosoma cruzi</i> I and IV strains.

a<p>Cumulative mortality from inoculation until the 90^th day after inoculation (d.a.i);</p>b<p>Cumulative mortality from the 90^th until the 180^th d.a.i.;</p>c<p>Percentage of animals presenting positive fresh blood examination within the first two months following inoculation and/or positive hemoculture and/or PCR on the 55^th d.a.i.;</p>d<p>Percentage of animals presenting positive ELISA in the 115^th d.a.i.;</p>e<p>Percentage of animals presenting positive ELISA in the 205^th d.a.i..</p>f<p>p<0.05: significant difference; N.S.: not significant.</p