| genetic structure of four species of triatoma (hemiptera: reduviidae) from argentina. | the genetic structure of triatoma guasayana wygodzinsky & abalos, t. sordida (stål), t. platensis neiva, and t. infestans (klug) was compared by starch gel electrophoresis. in total, 17 enzyme loci were analyzed in t. infestans and 14 loci in the other three species. zymograms were useful in species identification. icdh-2 and hk-1 are diagnostic loci, and icdh-1, hk-2, es-1, and es-2 are helpful in distinguishing these species. the proportion of polymorphic loci for the four species (range, 52.9 ... | 1995 | 7608918 |
| dispersive flight and house invasion by triatoma guasayana and triatoma sordida in argentina. | flight activity and invasion of houses by triatoma sordida and t. guasayana were studied in the province of santiago del estero, argentina. spontaneous findings of both species in houses were recorded from 1982 to 1989. light trap collections were performed in 1982, 1983 and 1984, at the woods surrounding the settlements of amamá (43 houses) and trinidad (19 houses). most of the 101 triatomines collected, were unfed and negative for trypanosoma cruzi. t. guasayana predominated over t. sordida, a ... | 1993 | 8246755 |
| potential colonization of the peridomicile by triatoma guasayana (hemiptera:reduviidae) in santiago del estero, argentina. | sylvatic triatomines might use the peridomicile as a 1st step in the process of domiciliation. therefore, we evaluated the capability of sylvatic species to colonize the peridomicile of a rural area in the province of santiago del estero, argentina. the research was carried out in 6 houses in the village of trinidad. the person per hour capture method was employed to determine the presence of triatomines in all the buildings (n = 44). dispersing adults were collected by means of light traps and ... | 1996 | 8699459 |
| spatial distribution of triatoma guasayana (hemiptera:reduviidae) in hardwood forest biotopes in santiago del estero, argentina. | in the study area triatoma guasayana wygodzinsky & abalos is the only wild triatomine found sympatric with triatoma infestans (klug) in peridomestic premises. the trypanosoma cruzi chagas wild cycle is centered around the same biotopes occupied by t. guasayana, which are also visited mainly by opossums with annual prevalences of 29-50%. twelve hectares were sampled for 4 consecutive years during all seasons. during that time, 420 t. guasayana individuals were collected in 11.3% of 1,188 biotopes ... | 1997 | 9103752 |
| infection of triatoma guasayana, triatoma sordida and triatoma infestans by trypanosoma cruzi from a naturally infected opossum. | | 1997 | 9332580 |
| evaluation of dogs as sentinels of the transmission of trypanosoma cruzi in a rural area of north-western argentina. | dogs, the main domestic reservoirs of trypanosoma cruzi in the argentine chaco, may be useful as sentinels of vector-mediated transmission of trypanosoma cruzi in control programmes if canine infections acquired by all other routes could be excluded. in the present study, in the province of santiago del estero, argentina, the dog populations in the neighbouring villages of amamá, trinidad, mercedes, villa matilde and pampa pozo were studied immediately before spraying of residual insecticides (i ... | 1998 | 9924546 |
| monitoring house reinfestation by vectors of chagas disease: a comparative trial of detection methods during a four-year follow-up. | domestic reinfestations by triatomine bugs were monitored after application of deltamethrin and apparent elimination of triatoma infestans in amama and other nearby rural villages, north-west argentina, from 1992 to 1996. the five methods used were sensor boxes, sheets of pink typing-paper, timed manual catches by a skilled three-person team aided by a flushing-out agent, collections by house-dwellers, and knockdown using insecticide fumigant canisters. in bedrooms, house-dwellers collected t. i ... | 1999 | 10206120 |
| ecogenetics of triatoma sordida and triatoma guasayana (hemiptera: reduviidae) in the bolivian chaco. | triatoma guasayana and two putative cryptic species pertaining to t. sordida complex (named groups 1 and 2) occur in sympatry in the bolivian chaco. using multilocus enzyme electrophoresis and subsequent genetic analysis, our work assesses their population distribution and dispersal capacity in domestic, peridomestic, and silvatic environments. our collections by light trap in the silvatic environment indicated a predominance of t. guasayana and t. sordida group 2 and a lesser abundance of t. so ... | 1999 | 10446000 |
| trypanosoma cruzi infection in triatoma infestans and other triatomines: long-term effects of a control program in rural northwestern argentina. | the prevalence of trypanosoma cruzi infection in triatoma infestans, triatoma guasayana, and triatoma sordida was evaluated in amamá and other neighboring rural villages in northwestern argentina for five years after massive spraying with deltamethrin in 1992 and selective sprays thereafter. local residents and expert staff collected triatomines in domiciliary and peridomestic sites. during 1993-1997, the prevalence of t. cruzi was 2.4% in 664 t. infestans, 0.7% in 268 t. guasayana, and 0.2% in ... | 1999 | 10446505 |
| small-scale field trial of a sensing device for detecting peridomestic populations of triatoma infestans (hemiptera: reduviidae) in northwestern argentina. | two prototypes of sensing devices for detecting peridomestic populations of triatoma infestans klug were tested in paired trials with bamboo canes in amamá and nearby rural villages under triatomine surveillance. in infested peridomestic structures housing domestic animals, 1-2 pairs of numbered devices were placed per test site, left for 3-9 nights, and inspected for evidence of infestation. prototype a was a black plastic cylinder 19 cm high and 10 cm diameter, with a screw cap on the top, 2 o ... | 1999 | 10593096 |
| peridomestic distribution of triatoma garciabesi and triatoma guasayana in north-west argentina. | the reduviid bugs triatoma garciabesi carcavallo et al. (hemiptera: reduviidae: triatominae), previously known as t. sordida ståhl in the semi-arid chaco region, and t. guasayana wygodzinsky & abalos, vectors of trypanosoma cruzi chagas (kinetoplastida: trypanosomatidae), were found to occupy wide but different ranges of ecotopes in the peridomestic environment. at amamá and nearby rural villages in north-western argentina, a combined total of 1233 specimens were collected from 325/2314 (14%) si ... | 2000 | 11129702 |
| a simple method to identify triatomine (hemiptera: reduviidae) feces in sensing devices used in vector surveillance programs. | we successfully applied the phenolphthalin (kastle-meyer) test used in forensic chemistry to distinguish between feces from triatomines and other domestic arthropods in sensing devices used for vector surveillance. all black or dark brown, but not white or yellow, fecal smears from laboratory-reared or field-collected triatoma infestans klug, triatoma guasayana wydgozinsky & abalos, triatoma sordida ståhl (recently revalidated as triatoma garciabesi carcavallo, cichero, martínez, prosen & ronder ... | 2001 | 11296815 |
| flight and nutritional status of sylvatic triatoma sordida and triatoma guasayana. | nutritional status relating to flight activity was investigated in natural populations of triatoma sordida and t. guasayana during the dry season in the bolivian chaco. the peak flight activity of both species was unimodal and covered the period 61-180 min after sunset. the weight of insects was used as the indicator of nutritional status. interspecies comparisons employing the same sex and type of capture showed a higher weight for t. guasayana. no significant difference according to weight was ... | 2001 | 11313649 |
| characterization of triatoma guasayana biotopes in a hardwood forest of santiago del estero, argentina. | triatoma guasayana is a silvatic triatomine species distributed in argentina, bolivia and paraguay. the study was performed in a secondary forest of santiago del estero, argentina. the abundance of t. guasayana was evaluated by census in the following wild biotopes: quimiles (opuntia quimilo), chaguares (dry bromeliads), logs and underground burrows. ten biotopes of each type were dismantled in winter (august) and another 40 in summer (january); all fauna was recorded. the biotopes most infested ... | 2001 | 11391416 |
| active dispersal of natural populations of triatoma infestans (hemiptera: reduviidae) in rural northwestern argentina. | an empirical model of flight initiation coupled with data from a longitudinal study predicted that the flight dispersal of triatoma infestans from peridomestic sites was more likely to occur in late summer. to partially test this prediction, we operated 11-12 black light traps from 1945 to 2200 hours in march 2003 in two villages in northern argentina. all peridomestic sites around the light traps were later inspected to assess the relative abundance and nutritional status of t. infestans at eac ... | 2004 | 15311452 |
| distribution and pathogenicity of trypanosoma cruzi isolated from peridomestic populations of triatoma infestans and triatoma guasayana from rural western argentina. | we assessed the distribution of trypanosoma cruzi infection in peridomestic triatomines collected manually at a district-wide scale in rural villages around olta, western argentina, and typed the isolated strains according to their pathogenicity to laboratory mice. of 1623 triatomines examined, only 14 (0.9%) were infected with t. cruzi based on microscopical examination of feces. the prevalence of t. cruzi infection was 0.8% in triatoma infestans, 2.3% in t. guasayana, and nil in t. garciabesi, ... | 2005 | 16021298 |
| spatiotemporal patterns of reinfestation by triatoma guasayana (hemiptera: reduviidae) in a rural community of northwestern argentina. | triatoma guasayana (wygodzinsky & abalos) is a secondary vector of trypanosoma cruzi (chagas), the etiologic agent of chagas disease, in the chaco region of argentina, bolivia, and paraguay. the spatial distribution of t. guasayana in a rural community in northwestern argentina is described and analyzed using very high spatial resolution satellite imagery, geographic information systems, and spatial statistics. since a 1992 residual spraying with insecticides of all houses, site-specific domesti ... | 2005 | 16119545 |
| pcr-based screening and lineage identification of trypanosoma cruzi directly from faecal samples of triatomine bugs from northwestern argentina. | this study applied improved dna extraction and polymerase chain reaction strategies for screening and identification of trypanosoma cruzi lineages directly from faeces of triatomines collected in a well-defined rural area in northwestern argentina. amplification of the variable regions of the kinetoplastid minicircle genome (kdna-pcr) was performed in faecal lysates from 33 microscope (mo)-positive and 93 mo-negative triatoma infestans, 2 mo-positive and 38 mo-negative triatoma guasayana and 2 m ... | 2006 | 16393354 |
| differential detection of blastocrithidia triatomae and trypanosoma cruzi by amplification of 24salpha ribosomal rna genes in faeces of sylvatic triatomine species from rural northwestern argentina. | flagellates indistinguishable from trypanosoma cruzi were detected by microscopy in faecal samples of 2/110 triatoma guasayana and 2/283 triatoma garciabesi captured in a rural area of northwestern argentina. inoculation of faecal homogenates to mice followed by xenodiagnosis, haemoculture, histopathology and culture from cardiac homogenates, and pcr based on t. cruzi minicircle and nuclear sequences failed to detect t. cruzi infection, pointing to another trypanosomatidean. a pcr strategy targe ... | 2006 | 16887092 |
| seasonal variations in active dispersal of natural populations of triatoma infestans in rural north-western argentina. | the flight dispersal of triatoma infestans klug (hemiptera: reduviidae) is one of the main mechanisms determining community re-infestation after control interventions. an empirical model of flight initiation coupled with data from a longitudinal study predicted that the flight dispersal of t. infestans would peak in summer. to test this prediction, longitudinal light trap collections were conducted during 3-8 nights in march (late summer), july (winter) and november (spring) 2003, and in march 2 ... | 2006 | 17044877 |
| environmental and demographic factors determining the spatial distribution of triatoma guasayana in peridomestic and semi-sylvatic habitats of rural northwestern argentina. | triatoma guasayana (wygodzinsky & abalos), a sylvatic vector of chagas' disease, occurs in natural and peridomestic habitats of the dry chaco region of argentina, bolivia and paraguay. ten-year retrospective spatial analyses of peridomestic t. guasayana abundance in the rural community of amamá were expanded to the neighbouring community of trinidad in northwestern argentina. the distribution of t. guasayana in domiciles, peridomiciles (storerooms, chicken coops and corrals) and natural habitats ... | 2008 | 18816276 |
| prevalence and distribution of parasites and pathogens of triatominae from argentina, with emphasis on triatoma infestans and triatoma virus trv. | chagas' disease is the most important endemic arthropod-zoonosis in argentina with an estimated 1.6 million people infected with the causative agent trypanosoma cruzi. triatoma infestans is the main vector of chagas' disease in argentina. a survey for parasites and pathogens of triatominae was conducted from august 2002 to february 2005. collections of insects were made in domiciles, peridomiciles, and in the natural habitats of the triatominae. insects from these collections were dissected and ... | 2009 | 19660466 |
| vectorial capacity of triatoma guasayana (wygodzinsky & abalos) (hemiptera: reduviidae) compared with two other species of epidemic importance. | triatoma guasayana (wygodzinsky & abalos) is a peridomestic triatomine with epidemiological importance in bolivia, that may play an important role in the transmission of trypanosoma cruzi (chagas). in this study, two parameters of vectorial capacity were evaluated: the interval of feeding-defecation time and metacyclogenesis, in adult males and females and nymphal instars ii to v of t. guasayana with comparisons with triatoma infestans (klug) and t. sordida (stal). the results showed a close rel ... | 2010 | 21120391 |
| dispersal of triatoma infestans and other triatominae species in the arid chaco of argentina: flying, walking or passive carriage? the importance of walking females. | the aim of this paper was to analyse the active dispersal of triatoma infestans and the role of chickens as passive carriers of this insect in peridomestic areas of la rioja, argentina. to measure active dispersal, monthly catches were made on six consecutive nights for five months (in the warm season) using light traps (for flying insects) and sticky dispersal barriers (for walking insects). the nutritional and reproductive states of adults were evaluated. over the course of the sampling period ... | 2011 | 21537686 |
| first report of colonies of sylvatic triatoma infestans (hemiptera: reduviidae) in the paraguayan chaco, using a trained dog. | in the gran chaco region, control of triatoma infestans has been limited by persistent domestic infestations despite the efforts of the vector control services. in paraguay, this region is the highest endemic area in the country, showing high levels of indoor and outdoor infestation. although sylvatic t. infestans have been found in the bolivian and argentine chaco, similar searches for sylvatic populations of this species in paraguay had been unsuccessful over the last 20 years. here we present ... | 2011 | 21572522 |
| hosts and vectors of trypanosoma cruzi discrete typing units in the chagas disease endemic region of the paraguayan chaco. | active trypanosoma cruzi transmission persists in the gran chaco region, which is considered hyperendemic for chagas disease. understanding domestic and sylvatic transmission cycles and therefore the relationship between vectors and mammalian hosts is crucial to designing and implementing improved effective control strategies. here we describe the species of triatomine vectors and the sylvatic mammal reservoirs of t. cruzi, in different localities of the paraguayan and bolivian chaco. we identif ... | 2017 | 28179034 |
| invasion of rural houses by wild triatominae in the arid chaco. | triatomines are the vectors of trypanosoma cruzi, the etiologic agent of chagas disease, the main endemic disease affecting five to seven million people in latin america. besides triatoma infestans, the most important t. cruzi vector in the gran chaco region, other triatomine species associated with sylvatic birds and mammals are responsible for the maintenance of the wild cycle of t. cruzi. the present study aimed at evaluating the house invasion by sylvatic triatomine species in rural communit ... | 2016 | 27232130 |
| sources of blood meals of sylvatic triatoma guasayana near zurima, bolivia, assayed with qpcr and 12s cloning. | in this study we compared the utility of two molecular biology techniques, cloning of the mitochondrial 12s ribosomal rna gene and hydrolysis probe-based qpcr, to identify blood meal sources of sylvatic chagas disease insect vectors collected with live-bait mouse traps (also known as noireau traps). fourteen t. guasayana were collected from six georeferenced trap locations in the andean highlands of the department of chuquisaca, bolivia. | 2014 | 25474154 |
| seasonality and temperature-dependent flight dispersal of triatoma infestans (hemiptera: reduviidae) and other vectors of chagas disease in western argentina. | flight dispersal of triatominae is affected by climatic conditions and determines the spatiotemporal patterns of house invasion and transmission of trypanosoma cruzi chagas (kinetoplastida: trypanosomatidae). we investigated the detailed time structure and temperature dependencies of flight occurrence of triatoma infestans klug (hemiptera: reduviidae) and other triatomine species in a rural village of western argentina by taking advantage of the attraction of adult triatomines to artificial ligh ... | 2017 | 28605522 |
| chagas disease vector control and taylor's law. | large spatial and temporal fluctuations in the population density of living organisms have profound consequences for biodiversity conservation, food production, pest control and disease control, especially vector-borne disease control. chagas disease vector control based on insecticide spraying could benefit from improved concepts and methods to deal with spatial variations in vector population density. | 2017 | 29190728 |
| morphometric variability among the species of the sordida subcomplex (hemiptera: reduviidae: triatominae): evidence for differentiation across the distribution range of triatoma sordida. | the sordida subcomplex (triatominae) comprises four species, triatoma garciabesi, t. guasayana, t. patagonica and t. sordida, which differ in epidemiological importance and adaptations to human environments. some morphological similarities among species make taxonomic identification, population differentiation and species delimitation controversial. triatoma garciabesi and t. sordida are the most similar species, having been considered alternatively two and a single species until t. garciabesi w ... | 2017 | 28877741 |
| the cuticular hydrocarbons of the triatoma sordida species subcomplex (hemiptera: reduviidae). | the cuticular hydrocarbons of the triatoma sordida subcomplex (hemiptera: reduviidae: triatominae) were ana-lysed by gas chromatography and their structures identified by mass spectrometry. they comprised mostly n-alkanes and methyl-branched alkanes with one-four methyl substitutions. n-alkanes consisted of a homologous series from c21-c33 and represented 33-45% of the hydrocarbon fraction; n-c29 was the major component. methyl-branched alkanes showed alkyl chains from c24-c43. high molecular we ... | 2013 | 24037201 |