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Variation of the centroid size among ecotopes and gender of Triatoma maculata from Venezuela. The boxes show the isometric size differences of wings between ecotopes (D, domestic; PD, peridomestic; and S, wild) and sex (M, male and F, female), from different states and locations. Each box shows the mean (horizontal line inside the box), standard deviation (vertical line). The number of individuals was M, 242 (D, 29; PD, 172; and S, 43) and F, 250 (D, 24; PD, 158; and S, 63). p: statistical significant differences.
Source publication
Triatoma maculata is a wild vector of Trypanosoma cruzi, the causative agent of Chagas disease; its incursion in the domestic habitat is scant. In order to establish the possible domestic habitat of T. maculata, we evaluated wing variability and polymorphism of genotypic markers in subpopulations of T. maculata that live in different habitats in Ve...
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Chagas disease is caused by Trypanosoma cruzi, a protozoan parasite that displays considerable genetic diversity. Infections result in a range of pathological outcomes, and different strains can exhibit a wide spectrum of anti-parasitic drug tolerance. The genetic determinants of infectivity, virulence and therapeutic susceptibility remain largely...
Updated information of the dispersion dynamics of Chagas disease (CD) and a systemic analysis of these data will aid the early identification of areas that are vulnerable to transmission and enable efficient intervention. This work synthesized spatiotemporal information regarding triatomine fauna and analyzed this information in combination with th...
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Citations
... In the wild, T. maculata occupies arboreal ecotopes including trees, palms, and bird nests; some populations, however, have adapted to exploit peridomestic structures (with a preference for chicken coops) and can also infest houses (Abad-Franch et al., 2010;Abad-Franch & Gurgel-Gonçalves, 2021;Lent & Wygodzinsky, 1979). In Colombia and Venezuela, synanthropic T. maculata may carry T. cruzi at high frequencies and are likely involved in Chagas disease transmission (Blohm et al., 2022;García-Alzate et al., 2014;González-Brítez et al., 2010;Lent & Wygodzinsky, 1979;Rodríguez-Monguí et al., 2019). Although infection with T. cruzi has not been reported in T. maculata from Roraima, Brazil, local populations infest rural and urban dwellings and have bionomic characteristics (especially a very short feeding-to-defecation time), suggesting that the species might also transmit Chagas disease in this area (Abad-Franch et al., 2010;Ricardo-Silva et al., 2016). ...
... 264). Wing morphometrics and PCR-RFLP analyses of the nuclear β-tubulin and mitochondrial (mt) cytb genes showed moderate variation among Venezuelan populations (García-Alzate et al., 2014;González-Brítez et al., 2010). ...
... There is now fairly convincing evidence that T. maculata is not sister to T. pseudomaculata (dos Santos et al., 2007;Justi et al., 2014Justi et al., , 2016Kieran et al., 2021;Pita et al., 2016), as well as some evidence that it is probably an old taxon (Justi et al., 2016). However, only limited data are available on the levels of population phenotypic and genetic diversity within the species (dos Santos et al., 2007;García-Alzate et al., 2014;Monsalve et al., 2016). Here, we present new mtDNA-sequence and cytogenetic evidence revealing extensive genetic diversity among T. maculata populations sampled across the species' range-a finding that may have taxonomic implications for the systematics of the species and paves the way to elucidating the roles that genetically distinct geographic populations play in T. cruzi transmission. ...
Triatoma maculata (Hemiptera, Reduviidae, Triatominae) occurs across dry-to-semiarid ecoregions of northern South America, where it transmits Trypanosoma cruzi, causative agent of Chagas disease. Using 207 field-caught specimens from throughout the species' range, mitochondrial(mt) DNA sequence data, and cytogenetics, we investigated inter-population genetic diversity and the phylogenetic affinities of T. maculata. Mitochondrial DNA sequence analyses (cytb and nd4) disclosed a monophyletic T. maculata clade encompassing three distinct geographic groups: Roraima formation (Guiana shield), Orinoco basin, and Magdalena basin (trans-Andean). Between-group cytb distances (11.0-12.8%) were larger than the ~7.5% expected for sister Triatoma species; the most recent common ancestor of these T. maculata groups may date back to the late Miocene. C-heterochromatin distribution and the sex-chromosome location of 45S ribosomal DNA clusters both distinguished Roraima bugs from Orinoco and Magdalena specimens. Cytb genealogies reinforced that T. maculata is not sister to Triatoma pseudomaculata and probably represents an early (middle-late Miocene) offshoot of the 'South American Triatomini lineage'. In sum, we report extensive genetic diversity and deep phylogeographic structuring in T. maculata, suggesting that it may consist of a complex of at least three sibling taxa. These findings have implications for the systematics, population biology, and perhaps medical relevance of T. maculata sensu lato.
... T. maculata is a species with heterogeneous epidemiological relevance in Colombia and Venezuela. It has been found with high infection levels and an active role in T. cruzi transmission in the Caribbean region (Garcia-Alzate et al., 2014;Cantillo-Barraza et al., 2015;Hernandez et al., 2016). However, it has been reported without infection in other areas and is associated with birds (Guhl et al., 2007). ...
Background
Rhodnius prolixus is considered the most relevant Trypanosoma cruzi vector in Colombia and Venezuela due it is responsible for domestic transmission in both countries. However, a wild population of this species is distributed in the eastern plains of the Orinoco region and Amazonia jungle, where its epidemiological importance has not been sufficiently elucidated. This study aimed to assess epidemiological parameters of T. cruzi transmission in the Department of Vichada, Colombia.
Methods
We determined the characteristics of T. cruzi transmission using entomological studies in domestic and sylvatic ecotopes. We analyzed the T. cruzi infection in triatomine insects, identified blood meal sources, and conducted a serological determination of T. cruzi infection in scholar-aged children, domestic dogs, and wild hosts.
Results
Fifty-four triatomine bugs, 40 T. maculata and 14 R. prolixus were collected in peridomestic and sylvatic ecotopes. Infected R. prolixus was observed in La Primavera, Santa Rosalia, and Cumaribo municipalities. All the T. maculata bugs were not infected. Serological analysis indicated that two of 3,425 children were T. cruzi positive. The seroprevalence in domestic dogs was 10,5% (49/465). Moreover, 22 synanthropic mammals were sampled, being Didelphis marsupialis the most common. TcI genotype was detected in seropositive dogs, R. prolixus, and D. marsupialis.
Conclusion
The present work describes extra domestic R. prolixus and D. marsupialis in a sylvatic T. cruzi transmission cycle with transmission to humans and domestic dogs in Colombia’s Vichada Department.
... People transfer rural living conditions such as crops and infected domestic animals, which favor the maintenance of the periurban cycle. The maintenance of poultry attracts Triatoma maculata, and the association of rodents around the houses coexisting with Rhodnius prolixus are conditions already demonstrated in urban neighborhoods (24,(28)(29)(30). The biological cycle has moved from the wild environment to the peridomiciliary and domestic environment, demanding new control strategies such as vaccine production and urban planning to avoid the domiciliation of primary and secondary vectors in urban areas (31). ...
The infection with the hemoflagellate parasite Trypanosoma cruzi originates from America where the wildlife cycle remains to alternate between mammals and hematophagous triatomines. Transmission through contamination of the bite site by vector feces containing highly infectious forms of parasite or direct ingestion of T. cruzi-infected triatomines appear to be the dominant transmission mechanisms. Man joins the transmission when he enters this wild environment or takes the leaves of palms carrying vectors to build houses. Rural Chagas disease develops associated with populations of low economic resources, with infection and reinfection of vector bites since childhood, and the consequent evolution toward chronic cases in adults, when there is little therapeutic benefit to infected people. The progressive migration of people from rural to urban areas and the adaptation of vectors to the peripheries of cities due to displacement caused by deforestation or urbanization that has favored the presence of enzootic cycles with Panstrongylus geniculatus as the most widely distributed species and mammals (synanthropic and domestic) allow vector transmission by ingestion of food contaminated with excrements containing infectious trypomastigotes as the dominant transmission mechanism in the urban environment. Human-to-human transmissions through vertical mother–child infection, transfusions, organ transplants, and the possibility of sexual transmission, transform the epidemiology and the clinical evolution of Chagas disease in the urban environment. Vectors of American trypanosomiasis are no longer restricted to the endemic area, but its presence has been demonstrated in nonendemic areas of the United States, Asia, and other latitudes. The worldwide plague of bedbugs (Cimex lectularius) threatens the possibility of expansion of transmission since they are vectors susceptible to infection, transmission to mammals, trans-stadial penetration, and not being affected by T. cruzi infection at least experimentally. These factors, added to the presence of an unknown number of migrating Latin American asymptomatic carriers together with the presence of triatomines in other continents, have initiated the globalization of a pathology originating in the American continent. Only with an integrative approach, based on new and better tolerated and efficient drugs, vaccines and residual action insecticides, all of them included in an epidemiological surveillance program.
... Few vectors species were collected and 61.4% were positive to T. cruzi by PCR, such as T. maculata and P. geniculatus, important vectors with high frequency of T. cruzi infection in Venezuela [3,23] and in Colombia [6]. In particular, phenotype and genotype studies on T. maculata from Las Margaritas del Llano, have demonstrated the continuous circulation of this vector in peridomestic-domestic corridors, resulting in additional elements of epidemiological risk [15]. In all cases the DTU of T. cruzi was TcI, the main DTU obtained from triatomines, animals and humans in Venezuela [3,32]. ...
Introduction:
Trypanosoma cruzi, Trypanosoma rangeli and Leishmania spp. are parasites that coexist in several endemic areas. The identification of these parasites in hosts is important for the control programs.
Methods:
216 samples from human blood (101), blood of other mammals (45) and triatomine intestinal content and hemolymph (70), from an endemic area of Venezuela, were analysed. The samples were evaluated by; serology (only humans) and PCR for T. cruzi in human, other mammals and triatomines, PCR for T. rangeli in mammals-including human and triatomines and PCR for Leishmania in mammals-including human.
Results:
The 9.9% of the human samples were positive for T. cruzi by serology, 11.9% by PCR, 4% for T. rangeli PCR and none for Leishmania spp. PCR. 60% of the samples of other mammals showed DNA amplification for T. cruzi, 42.2% for T. rangeli and 4.4% for Leishmania spp. 61.4% of the triatomine samples showed DNA amplification for T. cruzi and 10% for T. rangeli.
Conclusions:
High T. cruzi infection was detected in mammals and triatomines compared with T. rangeli. Low leishmanial infection was detected in other mammals. It is the first time that T. cruzi/T. rangeli coinfection, in humans, Canis familiaris (dog), and Bos Taurus (cow), were reported world-wide, and that this coinfection was described in Tamandua tetradactyla (anteater) from Venezuela. The coinfection T. cruzi/T. rangeli in mammals-including humans and triatomines, and coinfection T. cruzi/Leishmania spp. in non-human mammals, show the risk for trypanosomic zoonoses in this endemic area.
... Previous studies revealed, for the first time, the existence of phenotypic (variations in wing insertions) and genotypic (specific patterns in mt Cytb and the b-tubulin gene amplification) markers of the domiciliation process for T. maculata, a secondary vector in Anzoátegui (García-Alzate et al. 2014). However, there are very few studies, about the existence of domiciled populations of R. prolixus and T. maculata in the same house. ...
The domiciliation of Triatoma maculata and Rhodnius prolixus and the entomological risk indicators for the transmission of Trypanosoma cruzi, an etiological agent of Chagas Disease-CD, were studied in rural villages of Anzoátegui state, Venezuela. Nightly home visits were made for 4 months/year, for 2 years, to search for and capture triatomines in human settlements. For six of the evaluated villages, 16.4% (11/67) of houses were found with triatomine infestation; obtaining 151 triatomines in all their ontogenetic stages, of which 54.3% (82/151) corresponded to T. maculata and 45.7% (69/151) to R. prolixus. In 7.5% of the evaluated houses, both species were presented in sympatry. Entomological indicators of transmission risk were higher for T. maculata in relation to R. prolixus. Inoculation of fecal flagellates of triatomines produced 2.92 × 105 flagellates/mL of blood in mean and 100% mortality in the murine model. Molecular tests (satellite DNA, kDNA and DTUs studies) demonstrated the presence of T. cruzi, all compatible with TcI. The food source determined by IESPA, revealed that R. prolixus showed less eclecticism in relation to T. maculata in the use of blood sources. This could be an indicator of an older domiciliation with low dispersion between ecotopes. The sympatry of T. maculata and R. prolixus had been recorded in natural niches, but for the first time it is recorded inside the houses in rural villages of the Anzoátegui state. Human dwellings can constitute an adequate niche, with available food sources for both triatomines species and with the risk of establishing AT/CD as zoonosis or zooanthroponosis.
... R. pallecens has a more extensive, potential latitudinal range compared to that previously reported in the literature, with more suitable areas in Costa Rica, . In addition, the T. maculata distribution model corresponds with previous records, mainly in Colombia, Venezuela, and northern Brazil [65][66][67][68]. However, the prediction of environmentally suitable areas for the occurrence of this species in Panama, where it has not been previously reported [68]. ...
Ecoepidemiological scenarios for Chagas disease transmission are complex, so vector control measures to decrease human-vector contact and prevent infection transmission are difficult to implement in all geographic contexts. This study assessed the geographic abundance patterns of two vector species of Chagas disease: Triatoma maculata (Erich-son, 1848) and Rhodnius pallescens (Barber, 1932) in Latin America. We modeled their potential distribution using the maximum entropy algorithm implemented in Maxent and calculated distances to their niche centroid by fitting a minimum-volume ellipsoid. In addition, to determine which method would accurately explain geographic abundance patterns, we compared the correlation between population abundance and the distance to the ecological niche centroid (DNC) and between population abundance and Maxent environmental suit-ability. The potential distribution estimated for T. maculata showed that environmental suit-ability covers a large area, from Panama to Northern Brazil. R. pallescens showed a more restricted potential distribution, with environmental suitability covering mostly the coastal zone of Costa Rica and some areas in Nicaragua, Honduras, Belize and the Yucatá n Peninsula in Mexico, northern Colombia, Acre, and Rondô nia states in Brazil, as well as a small region of the western Brazilian Amazon. We found a negative slope in the relationship between population abundance and the DNC in both species. R. pallecens has a more extensive potential latitudinal range than previously reported, and the distribution model for T. maculata corroborates previous studies. In addition, population abundance increases according to the niche centroid proximity, indicating that population abundance is limited by the set of scenopoetic variables at coarser scales (non-interactive variables) used to determine the ecological niche. These findings might be used by public health agencies in Latin America to implement actions and support programs for disease prevention and vector PLOS ONE PLOS ONE | https://doi.org/10.1371/journal.pone.
... Because this was an exploratory analysis with a low number of individuals, it was not possible to interpret the results without speculation. However, the occurrence of T. maculata in different habitats may suggest the ability of this vector to adapt to a variety of environments, which could have eco-epidemiological implications that are still not well known [4,[15][16][17]. In agreement with Noireau et al. [18], although anthropogenic environmental changes and successive damage to the habitats of triatomines could promote dispersal and favour the domiciliation process, the basic mechanisms of adaptation of these insects to artificial ecotopes remain poorly understood. ...
Background:
In Brazil, Triatoma maculata is only found in the State of Roraima and is a vector of Trypanosoma cruzi, the etiological agent of Chagas disease. It occurs in wild, peridomestic and domestic habitats, with an urban infestation in Boa Vista, the capital of this Brazilian state. The aim of this study was to assess the morphological variability of the T. maculata antennal phenotype in three populations of Roraima State, using the antennal sensilla pattern analyzed under optical microscopy.
Methods:
The number and distribution of four antennal sensilla types (bristles, thin and thick walled trichoidea, and basiconic) of three Brazilian populations of T. maculata from Roraima State were compared. Univariate and multivariate analyses were performed.
Results:
The antenna of T. maculata presented the four types of sensilla. According to the density and distribution of the antennal sensilla characteristics, the multivariate analyses showed that the laboratory population is morphologically structured. Urban specimens showed a pronounced phenotypic variability. The main differences were observed in the pedicel segment, and between males and females.
Conclusions:
We determined the antennal phenotype in three Roraima populations of T. maculata. These results support the idea that the patterns of antennal sensilla are sensitive markers for distinct populations in the Triatominae. The infestations of T. maculata in different habitats reinforces the ability of this vector to become adapted to a variety of environments, which, could have eco-epidemiological implications for the T. cruzi transmission that are still not well understood.
... Triatoma maculata has a wide geographical distribution in Colombia. We observed a high invasion of domestic ecotopes by this species (Fig. 2), consistent with other studies in Colombia, Brazil and Venezuela where this species even presents morphological and genetic changes across individuals collected in domestic ecotopes [26,27,[32][33][34]. Triatoma maculata has not been included in the vector control programs because its diet is mainly composed of bird blood [32,[35][36][37] and some studies have reported low frequency of infection in Brazil and Venezuela [36,38]. ...
... By contrast, herein the frequency of T. cruzi infection was 67.6% and the percentage of feeding with human blood was 75.0% with the presence of TcIDom in some specimens collected in peridomiciliary habitats. Recent studies in Colombia and Venezuela have revealed infection frequencies between 38.0 and 75.0% and the presence of "TcIb" genotype that is associated with the peridomestic cycle [26,27,33,34,39,40]. Regarding the DTUs herein detected, most of the specimens were infected with TcI and TcIII (sylvatic DTUs) and domestic specimens harbored TcIII suggesting how T. maculata can connect domestic and sylvatic transmision cycles (Fig. 4). ...
... Triatoma maculata has a wide geographical distribution in Colombia. We observed a high invasion of domestic ecotopes by this species (Fig. 2), consistent with other studies in Colombia, Brazil and Venezuela where this species even presents morphological and genetic changes across individuals collected in domestic ecotopes [26,27,[32][33][34]. Triatoma maculata has not been included in the vector control programs because its diet is mainly composed of bird blood [32,[35][36][37] and some studies have reported low frequency of infection in Brazil and Venezuela [36,38]. ...
... By contrast, herein the frequency of T. cruzi infection was 67.6% and the percentage of feeding with human blood was 75.0% with the presence of TcIDom in some specimens collected in peridomiciliary habitats. Recent studies in Colombia and Venezuela have revealed infection frequencies between 38.0 and 75.0% and the presence of "TcIb" genotype that is associated with the peridomestic cycle [26,27,33,34,39,40]. Regarding the DTUs herein detected, most of the specimens were infected with TcI and TcIII (sylvatic DTUs) and domestic specimens harbored TcIII suggesting how T. maculata can connect domestic and sylvatic transmision cycles (Fig. 4). ...
Background
Trypanosoma cruzi is the causative agent of Chagas disease. Due to its genetic diversity has been classified into six Discrete Typing Units (DTUs) in association with transmission cycles. In Colombia, natural T. cruzi infection has been detected in 15 triatomine species. There is scarce information regarding the infection rates, DTUs and feeding preferences of secondary vectors. Therefore, the aim of this study was to determine T. cruzi infection rates, parasite DTU, ecotopes, insect stages, geographical location and bug feeding preferences across six different triatomine species. MethodsA total of 245 insects were collected in seven departments of Colombia. We conducted molecular detection and genotyping of T. cruzi with subsequent identification of food sources. The frequency of infection, DTUs, TcI genotypes and feeding sources were plotted across the six species studied. A logistic regression model risk was estimated with insects positive for T. cruzi according to demographic and eco-epidemiological characteristics. ResultsWe collected 85 specimens of Panstrongylus geniculatus, 77 Rhodnius prolixus, 37 R. pallescens, 34 Triatoma maculata, 8 R. pictipes and 4 T. dimidiata. The overall T. cruzi infection rate was 61.2% and presented statistical associations with the departments Meta (OR: 2.65; 95% CI: 1.69–4.17) and Guajira (OR: 2.13; 95% CI: 1.16–3.94); peridomestic ecotope (OR: 2.52: 95% CI: 1.62–3.93); the vector species P. geniculatus (OR: 2.40; 95% CI: 1.51–3.82) and T. maculata (OR: 2.09; 95% CI: 1.02–4.29); females (OR: 2.05; 95% CI: 1.39–3.04) and feeding on opossum (OR: 3.15; 95% CI: 1.85–11.69) and human blood (OR: 1.55; 95% CI: 1.07–2.24). Regarding the DTUs, we observed TcI (67.3%), TcII (6.7%), TcIII (8.7%), TcIV (4.0%) and TcV (6.0%). Across the samples typed as TcI, we detected TcIDom (19%) and sylvatic TcI (75%). The frequencies of feeding sources were 59.4% (human blood); 11.2% (hen); 9.6% (bat); 5.6% (opossum); 5.1% (mouse); 4.1% (dog); 3.0% (rodent); 1.0% (armadillo); and 1.0% (cow). Conclusions
New scenarios of T. cruzi transmission caused by secondary and sylvatic vectors are considered. The findings of sylvatic DTUs from bugs collected in domestic and peridomestic ecotopes confirms the emerging transmission scenarios in Colombia.
... In Venezuela T. maculata is regarded as the second most important vector species in the transmission of Chagas disease, after Rhodnius prolixus. R. prolixus is related to domiciliated transmission, invasion and reinfestation of houses after control measures in Venezuela (Feliciangeli & Torrealba 1977, González-Brítez et al. 2010, Reyes-Lugo et al. 2011 where oral outbreaks have been reported, mainly related to the presence of sylvatic and peridomicile triatomine species (Rojas et al. 2008, García-Alzate et al. 2014, Alarcón de Noya et al. 2015. ...
... These processes stimulate adult dispersion, which might find a receptive environment in artificial ecotopes (Forattini et al. 1979, Aragão 1983, González-Brítez et al. 2010). In Venezuela this process has been described for T. maculata using geometric morphometry to analyse wings and by the variability in the b-tubuline marker, coupled with the presence of nymphs inside the houses (García-Alzate et al. 2014). In the present observation in Roraima, we found eggs, nymphs in all development stages and one adult, which is the first encounter of T. maculata colonising domiciles in Brazil. ...
During a medical entomology course in Boa Vista, Roraima, colonies of Triatoma maculata closely associated with pigeon nests were observed in concrete air-conditioner box located on the external plastered and cemented walls of a modern brick-built apartment block. In only one eight-hole ceramic brick, located inside one air-conditioner box, 127 specimens of T. maculata were collected. T. maculata is a recognised vector of Trypanosoma cruzi in the surrounding area and its domiciliation increases the risk of Chagas disease transmission.
