In this study, we evaluated the effect of the climatic season and infection by , etiological agent of Chagas disease, on the molting capacity of the triatomine vector endemic to Chile. We used wild-caught first-to-fourth instar nymphs during cooling (fall and winter) and warming (spring) periods. After capturing, nymphs were fed at the laboratory, and maintained under optimal rearing conditions.
View Article and Find Full Text PDFChagas disease is caused by Trypanosoma cruzi and transmitted by the triatomine Mepraia spinolai in the southwest of South America. Here, we examined the T. cruzi-infection dynamics of field-caught M.
View Article and Find Full Text PDFChagas disease is a public health problem in America. Its parasite, Trypanosoma cruzi, presents different discrete typing units (DTUs), colonizes organs of mammalian hosts in chronic infections, and presents tropism for particular organs in experimental infections. We evaluated T.
View Article and Find Full Text PDFThe etiologic agent of Chagas disease, Trypanosoma cruzi, is transmitted by hematophagous insect vectors that subsist on repeated blood meals over their lives separated by periods of fasting. Using naturally infected Mepraia spinolai, we measured the influence of parasite infection on this host vector's mortality during regular feeding and after fasting. After their capture, the insects were fed twice with uninfected mice to evaluate parasitic infection in their fecal samples by microscopic observation and PCR.
View Article and Find Full Text PDFBackground: Trypanosoma cruzi is a protozoan parasite that is transmitted by triatomine vectors to mammals. It is classified in six discrete typing units (DTUs). In Chile, domestic vectorial transmission has been interrupted; however, the parasite is maintained in non-domestic foci.
View Article and Find Full Text PDFChagas disease is a vector-borne disease caused by the parasite Trypanosoma cruzi, and transmitted by triatomine insects to several mammal species. In Chile, the wild triatomine species are the endemic Mepraia species, and the only domestic vector of Chagas disease is Triatoma infestans. The aim of this study was to determine the competence of M.
View Article and Find Full Text PDFBackground: Chagas disease caused by Trypanosoma cruzi is considered a major public health problem in America. After an acute phase the disease changes to a chronic phase with very low parasitemia. The parasite presents high genetic variability with seven discrete typing units (DTUs): TcI-TcVI and Tc bat.
View Article and Find Full Text PDFDifferent DNA markers to genotype Trypanosoma cruzi are now available. However, due to the low quantity of parasites present in biological samples, DNA markers with high copy number like kinetoplast minicircles are needed. The aim of this study was to complete a DNA assay called minicircle lineage specific-PCR (MLS-PCR) previously developed to genotype the T.
View Article and Find Full Text PDFMepraia species are hematophagous insects and the most important wild vectors of Trypanosoma cruzi, the causative agent of Chagas disease in southeastern South America. Because the domestic Triatoma infestans is already controlled, the transmission of different T. cruzi discrete typing units (DTUs) by Mepraia species deserves attention.
View Article and Find Full Text PDFChagas disease, which ranks among the world's most neglected diseases, is a chronic, systemic, parasitic infection caused by the protozoan Trypanosoma cruzi. Mepraia species are the wild vectors of this parasite in Chile. Host-parasite interactions can occur at several levels, such as co-speciation and ecological host fitting, among others.
View Article and Find Full Text PDFChagas disease is a zoonosis caused by the protozoan parasite Trypanosoma cruzi and transmitted by triatomine insects to several mammalian species acting as reservoir hosts. In the present study, we assess T. cruzi-prevalence and DTU composition of the endemic rodent Octodon degus from a hyper-endemic area of Chagas disease in Chile.
View Article and Find Full Text PDFThere are currently no biomarkers to assess which patients with chronic indeterminate Chagas disease will develop heart disease and which will spend their entire life in this state. We hypothetize that the parasite burden and Trypanosoma cruzi genotypes are related to the presence of heart disease in patients with Chagas disease. This study is aimed to investigate the parasite burden and T.
View Article and Find Full Text PDFThe etiologic agent of Chagas disease is Trypanosoma cruzi, a protozoan whose life cycle involves obligatory passage through vertebrate and invertebrate hosts in a series of stages. The aim of this study was to explore the transferability of mixed discrete typing units (DTUs) of T. cruzi present in chronic chagasic patients when passed through an invertebrate host during xenodiagnosis (XD) and then when transferred to axenic cultures to obtain T.
View Article and Find Full Text PDFWe evaluated Trypanosoma cruzi infection rates by means of minicircle DNA-based polymerase chain reactions (PCRs) in 70 starved Mepraia gajardoi from northern Chile and 65 M. spinolai from central Chile after feeding. Immediately after collection in the field, 20% of M.
View Article and Find Full Text PDFBackground: Chagas disease is a neglected illness caused by the Trypanosoma cruzi parasite, which widely affects American communities. This study attempted to identify T. cruzi genotypes circulating in four indigenous communities of the Sierra Nevada of Santa Marta, Colombia, to investigate parasite transmission dynamics in these communities.
View Article and Find Full Text PDFAntimicrob Agents Chemother
September 2013
Currently, evaluation of drug efficacy for Chagas disease remains a controversial issue with no consensus. In this work, we evaluated the parasitological efficacy of Nifurtimox treatment in 21 women with chronic Chagas disease from an area of endemicity in Chile who were treated according to current protocols. Under pre- and posttherapy conditions, blood (B) samples and xenodiagnosis (XD) samples from these patients were subjected to analysis by real-time PCR targeting the nuclear satellite DNA of Trypanosoma cruzi (Sat DNA PCR-B, Sat DNA PCR-XD) and by PCR targeting the minicircle of kinetoplast DNA of T.
View Article and Find Full Text PDFWe evaluated Trypanosoma cruzi infection in 397 wild Mepraia gajardoi specimens from five coastal localities in northern Chile by detection of minicircle DNA by polymerase chain reaction. The wild capture sites were classified into two ecotopes: a fully wild ecotope (ecotope 1) and a wild ecotope near human dwellings (ecotope 2). Infection rates varied between 11% and 27%.
View Article and Find Full Text PDFThe objective of this study was to determine the presence of Trypanosoma cruzi in blood samples of mothers with chronic Chagas disease and their newborn by conventional PCR targeted to minicircle kinetoplastidic DNA (kDNA), and to determine the lineages in mother/newborn pairs of the congenital cases by hybridization assays with probes belonging to the TcII, TcI and TcV Discrete Typing Units (DTU). In 63 (57.2%) of the mothers the presence of circulating T.
View Article and Find Full Text PDFIn Chile, the main vector of Chagas disease, Triatoma infestans, is under control after insecticide spraying. However, it has been found colonizing wild habitats. This study evaluated Trypanosoma cruzi infection of sylvatic and domiciliary T.
View Article and Find Full Text PDFThe aim of this study was to establish the phylogenetic relationships of trypanosomes present in blood samples of Bolivian Carollia bats. Eighteen cloned stocks were isolated from 115 bats belonging to Carollia perspicillata (Phyllostomidae) from three Amazonian areas of the Chapare Province of Bolivia and studied by xenodiagnosis using the vectors Rhodnius robustus and Triatoma infestans (Trypanosoma cruzi marenkellei) or haemoculture (Trypanosoma dionisii). The PCR DNA amplified was analyzed by nucleotide sequences of maxicircles encoding cytochrome b and by means of the molecular size of hyper variable regions of minicircles.
View Article and Find Full Text PDFFifty-six Trypanosoma cruzi stocks from Chile and neighboring countries and different hosts, humans, and Triatoma infestans and Mepraia sp., vectors of domiciliary and natural environments were characterized by using three molecular markers. These were cytochrome b (Cyt b) gene sequencing, minicircle DNA blotting, and hybridization with five genotype-specific DNA probes and nuclear analysis of 1f8 and gp72 by polymerase chain reaction-restriction fragment length polymorphism.
View Article and Find Full Text PDFCongenital Chagas disease acquired special importance in Chile after the certification of the control of Triatoma infestans and transmission by blood donors affected with Trypanosoma cruzi. In order to establish adequate protocols for intervention and control in infected mother-neonate pairs in endemic zones of Chagas disease, we present partial results (2005-2008) of a pilot project which is being carried out in the Province of Choapa, IV Region, Chile, whose objectives are: determine the current prevalence of the disease in pregnant women, estimate the incidence of vertical transmission of T. cruzi to newborns, determine the lineages of the parasite present in mothers who do and do not transmit the disease, determine the prevalence of Chagas disease in maternal grandmothers of neonates and study placental histopathology.
View Article and Find Full Text PDFDiagn Microbiol Infect Dis
November 2010
Although Trypanosoma rangeli is harmless for humans, it is a serious problem since it may be confused with diagnosis of Trypanosoma cruzi, the etiologic agent of Chagas disease. Both parasites overlap geographically, share antigenic protein, and are able to infect the same Triatominae vector and vertebrate host, including human. Our objective was to differentiate T.
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