Background: Field ecologists often rely on mark-release-recapture (MRR) experiments to estimate population dynamics parameters for a given species. In the case of a medically important taxon, i.e.
View Article and Find Full Text PDFWe used the gut contents of triatomines collected from rural areas of Ceará State, northeastern Brazil, to identify their putative hosts via vertebrate cytb gene sequencing. Successful direct sequencing was obtained for 48% of insects, comprising 50 Triatoma brasiliensis, 7 Triatoma pseudomaculata, and 1 Rhodnius nasutus. Basic local alignment search tool (BLAST) procedure revealed that domestic animals, such as chickens (Gallus gallus) and goats (Capra hircus), are the main food source, including in sylvatic environment.
View Article and Find Full Text PDFPalms are ubiquitous across Neotropical landscapes, from pristine forests or savannahs to large cities. Although palms provide useful ecosystem services, they also offer suitable habitat for triatomines and for Trypanosoma cruzi mammalian hosts. Wild triatomines often invade houses by flying from nearby palms, potentially leading to new cases of human Chagas disease.
View Article and Find Full Text PDFBackground: Chagas disease is caused by Trypanosoma cruzi, which is transmitted by triatomine vectors. The northeastern region of Brazil is endemic for Chagas disease and has the largest diversity of triatomine species. T.
View Article and Find Full Text PDFChagas disease was investigated in two new settlements of landless rural workers inhabiting prefabricated, triatomine-proof houses and in four neighboring older communities where mud huts were still well suitable for vectors. Through a cross-sectional survey and entomological assessment, we surveyed 148 houses/families in the two new settlements and in 47 houses/families in the four older localities. We determined seroprevalence of Chagas disease through IFI and Elisa (eluates) assays and searched for vectors in the domestic and peridomestic environments.
View Article and Find Full Text PDFBackground: After the control of the main modes of Chagas disease (CD) transmission in most endemic countries, it is important to identify the participation of native sylvatic vectors in CD transmission. Although CD is not considered endemic in Rio de Janeiro State (RJ), Brazil, we identified patients with CD born in RJ and investigated the possible autochthonous transmission in the state.
Methods: Patients born in RJ and followed in our institution between 1986 and 2011 were retrospectively analyzed.
Background: Understanding the drivers of habitat selection by insect disease vectors is instrumental to the design and operation of rational control-surveillance systems. One pervasive yet often overlooked drawback of vector studies is that detection failures result in some sites being misclassified as uninfested; naïve infestation indices are therefore biased, and this can confound our view of vector habitat preferences. Here, we present an initial attempt at applying methods that explicitly account for imperfect detection to investigate the ecology of Chagas disease vectors in man-made environments.
View Article and Find Full Text PDFTriatoma brasiliensis is the most important vector of Chagas disease in the Caatinga eco-region of northeastern Brazil. Wild T. brasiliensis populations have been reported only from rocky outcrops.
View Article and Find Full Text PDFChagas disease was investigated in four periurban areas of Ceará state, northeastern Brazil, through serological, parasitological and molecular methods in humans, reservoirs and vectors. A cross-sectional survey revealed a seroprevalence rate of 1.2% (13/1076 residents, six also proving positive through PCR).
View Article and Find Full Text PDFAn entomological survey was carried out in four rural localities situated in the state of Ceará, assessing Chagas disease seroprevalence in man, focusing on the presence of vectors in natural foci contiguous to the domestic and peridomestic environments. Fifty-three Triatoma brasiliensis, nine T. pseudomaculata and 71 Rhodnius nasutus were collected in their natural habitats as far as 10 m from the houses, and 663, 59 and 8 respectively were captured in peridomestic artificial structures, adjacent to the houses, including henhouses, pigpens, corrals, perches and piles of bricks, tiles and wood.
View Article and Find Full Text PDFIn order to mark Triatoma brasiliensis, the vector of Chagas disease in Brazil, two chemical compounds, rubidium chloride (RbCl) and chromium chloride (CrCl₃), were tested. First, 199 N2-N5 nymphs were fed on blood with 0.025M RbCl.
View Article and Find Full Text PDFThe aim of this work was to study the interaction between Trypanosoma cruzi-1 and Triatoma brasiliensis. A group of 1st instar nymphs was initially fed on T. cruzi-infected mice and a control group was fed on uninfected mice.
View Article and Find Full Text PDFWe assessed some ecological parameters of Triatoma brasiliensis in rock piles in the state of Ceará during the rainy and dry seasons. The greatest density was in April (median = 12.5 triatomines/site).
View Article and Find Full Text PDFThe importance of Rhodnius nasutus in the transmission of Chagas disease in northeastern Brazil was investigated regarding feeding and defecation patterns of this triatomine under laboratory conditions. An average of 30 samples were studied for each instar, from fourth-instar nymphs onward. On average, 86.
View Article and Find Full Text PDFWith the aid of live-bait traps, we studied the risk that Copernicia prunifera palm trees, present in both periurban and rural localities of an endemic Brazilian northeast Chagas disease region, represent to domestic infestation by Rhodnius nasutus. In this area, this important vector has been encountered harboring and transmitting Trypanosoma cruzi, the etiologic agent of the American trypanosomiasis, to mammals, possibly including humans. Results indicate that this bug colonizes C.
View Article and Find Full Text PDFA cross-sectional study on Chagas disease that examined the populations of four localities (n masculine = 541 inhabitants) in the municipality of Jaguaruana, State of Ceará, showed seroprevalence of Chagas infection of 3.1%, as assessed by indirect immunofluorescence, indirect hemagglutination and ELISA tests. The rate was higher among adults over 50 years old, without any difference in relation to sex.
View Article and Find Full Text PDFArtificial ecotopes of 121 peridomiciliary environments in four rural localities in the state of Ceará, Brazil, were studied and the type of material of the ecotopes was identified as triatomine infestation. Two thousand two hundred and four Triatoma brasiliensis Neiva, 340 Triatoma pseudomaculata Corrêa and Espínola, 121 Rhodnius nasutus Stall, and 5 Panstrongylus lutzi (Neiva and Pinto) were captured. Out of the 323 ecotopes found (X = 2.
View Article and Find Full Text PDFEighteen Trypanosoma cruzi strains isolated from naturally infected triatomines were studied genetically. The majority of the strains were from Triatoma brasiliensis, the principal vector of Chagas disease in the northeast of Brazil. Multilocus enzyme electrophoresis (MLEE) and randomly amplified polymorphic DNA (RAPD) analyses were used to investigate the genotypic diversity and the spread of the T.
View Article and Find Full Text PDFComp Biochem Physiol B Biochem Mol Biol
December 2004
The characterization of sulfated glycosaminoglycans (GAGs) in hematophagous arthropod vectors in general has been limited, with the exception of the studies in the triatomine Rhodnius prolixus. Heparan sulfate (HS) and chondroitin sulfate (CS) were previously identified and structurally characterized in extracts of whole bodies of fourth instar larvae of R. prolixus.
View Article and Find Full Text PDFIn order to assay the triatomine infestation and domiciliation in the rural area of Jaguaruana district, state of Ceará, Brazil, we studied, from November 2000 to April 2002, 4 localities comprising 158 domiciles as a whole, with an average of 4 inhabitants/house, who are dwelling in there for more than 7 years. Most houses have tile-covered roofs and the walls built with plaster-covered bricks (57%), followed by bricks without plaster (33%), and mud walls (7.5%).
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