ABSTRACT Background: Triatominae are vectors of the protozoan Trypanosoma cruzi, the causative agent of Chagas disease. This study aims to report an infestation on Triatominae colonies by a beetle, previously identified as a pest. Methods: The management of these colonies should be improved to maximize their usefulness, and factors that may cause harm to them should be avoided as much as possible. Results: This is the first report on a coleopteran infestation on living Triatominae colonies worldwide. Conclusions: The present record provides an important warning to researchers who maintain insectaries in general, especially those who rear triatomines, to carry protective measures against such invasions.

ABSTRACT Background: Triatomines infest atypical public spaces in the Western Amazon. Methods: Frequent visitors to these spaces captured the insects in the state of Acre, Brazil (Rio Branco and Cruzeiro do Sul). Results: Six insects were found in a penitentiary, a church, a school, a university, a hospital, and a health center. Five of the insects were adults (three positive for Trypanosoma cruzi) and one was a nymph. Conclusions: This is the first report of triatomine occurrence in schools or churches. These data are important for implementing surveillance strategies and alerting individuals about possible changes in Chagas disease transmission dynamics.

ABSTRACT Background: Trypanosoma cruzi presents great variability in morphology, virulence, pathogenicity, avoidance of the host immune system, and antigenic constitution, associated with different clinical manifestations of the disease. Methods: Two strains of T. cruzi were cultivated in liver infusion tryptose to determine growth kinetics, morphometry and molecular characterization using restriction fragment length polymorphism polymerase chain reaction. Results: The biological parameters showed sharp growth by the 7th day. Morphologically, both strains showed short and thin forms and were classified as Group I. Conclusion: Group TcI presents cardiac manifestations and T. sherlocki is adapting to the home environment, requiring attention to future problems.

ABSTRACT Background: The subfamily Triatominae, which comprises 157 species, carries the protozoan Trypanosoma cruzi, the etiological agent of Chagas disease. This short communication reports for the first time the occurrence of Rhodnius montenegrensis in Bolivia. Methods: Active searches were carried out on palm trees of the genus Oenocarpus in Beni district, Bolivia. Results: Fifteen R. montenegrensis specimens were collected from a rural area of the Beni district, Bolivia, and tested positive for T. cruzi. Conclusions: This new report expands the geographic distribution of the species in Latin America. Due to their ability to transmit trypanosomatids, the species deserves the attention of vector control programs.

Abstract The chemical hydroxymethylation of the antimicrobial nitrofurazone leads to the prodrug NFOH, also increases the anti-T. cruzi activities (in vitro and in vivo), as well as showed non-genotoxic (Ames and micronucleus assays). In the present study, we assessed the anti-T. cruzi effect of the NFOH In vivo - in acute Swiss and C57Bl/6 experimental Chagas models. The treatment started at 5 days post-infection during 20 consecutive days (orally, once day, 150mg/kg), and the parasitaemia as well as histopathology analysis were performed. In both experimental murine models, NFOH was able to reduce parasitemia blood avoiding parasitic reactivation, during immunosuppression period (dexamethasone 5mg/kg, 14 days), in 100% of the mice, and decrease tissue parasite nests, demonstrating absence of amastigote forms in all organs (100%) analyzed, data similar to benznidazole (BZN). Therefore, the results shown here pointing to the NFOH as promising compound for further preclinical studies, being a high potential drug to effective and safe chemotherapy to Chagas disease.

Abstract INTRODUCTION: Triatoma lenti and Triatoma sherlocki are endemic species of the State of Bahia, located in northeastern Brazil, where they have records of domiciliation in the human environment. In view of the epidemiological aspect and taxonomic importance of these species for the systematics of the Triatoma genus, a study was carried out with nymphs of all five instars. METHODS An extensive review of studies on nymphs from the subfamily Triatominae is presented. Morphology was studied using a scanning electron microscope and morphometric analyses. RESULTS: The morphological study allowed us to characterize and discriminate species by means of scanning electron microscope of the last abdominal segment. In addition, the results show morphometric variability, with the total size of the head that best discriminates the species. CONCLUSIONS: Studies on nymphs are fundamental to the ecosystem; however, the literature on the immature forms of certain groups is scarce, difficult to use, or nonexistent. Therefore, this study includes morphological and morphometric data of the nymphal instars of T. lenti and T. sherlocki, corroborating the specific taxonomy of these species.

Abstract INTRODUCTION: This study reports the first occurrence of Psammolestes tertius (Hemiptera, Reduviidae, Triatominae) in the state of Sergipe, Brazil. METHODS: In 2020, 95 specimens were collected from the municipality of Porto da Folha, Sergipe, Brazil. RESULTS: This finding expands the geographical distribution of the species from 15 states in Brazil to 16 and increases the biodiversity of triatomines in the state of Sergipe. CONCLUSIONS: The presence of P. tertius in the state of Sergipe demonstrated a wider distribution of this species in northeastern Brazil.

Abstract INTRODUCTION This study confirms the occurrence of Psammolestes tertius Lent & Jurberg, 1965 (Hemiptera, Reduviidae, Triatominae) in the state of Paraná, Brazil. METHODS: In 2002, a male specimen of P. tertius was collected in the municipality of Porto Rico, Paraná, Brazil. RESULTS: This finding adds to the data on the geographical distribution of P. tertius from 14 to 15 known occurrences in Brazilian states and, therefore, reports the increase in the diversity of triatomines in Paraná. CONCLUSIONS: The presence of P. tertius in the state of Paraná demonstrates that the biodiversity of these insects may have been underestimated.

Abstract INTRODUCTION: Triatomines are hematophagous insects that are important to public health since they are the vectors of American Trypanosomiasis. The objective of this study was to describe the occurrence of triatomines in homes in Cruzeiro do Sul, Acre, Brazil. METHODS The specimens were collected by an active search inside homes and also by a passive search by the residents. RESULTS: A total of 55 triatomines were captured comprising of 5 species each of the genera Rhodnius, Eratyrus, and Panstrongylus. No colonies were detected, ruling out the possibility of domiciliation. CONCLUSIONS: Information on regional epidemiological dynamics contributes to the prevention and control of disease.

Abstract INTRODUCTION: Triatomines are insect vectors of Trypanosoma cruzi, the etiological agent of Chagas disease. METHODS: Triatomines were collected from households and by dissecting palm trees in the peri-urban areas of Cruzeiro do Sul (Acre); they were identified using a specific key and via genital analyses. Trypanosomatid infection was determined through microscopy and polymerase chain reaction. RESULTS: In total, 116 triatomines of the species Eratyrus mucronatus, Rhodnius pictipes, R. stali, and R. montenegrensis were collected, of which 13.8% were positive for T. cruzi. CONCLUSIONS: Four species of triatomines presented an infection rate above 13% in the Boca do Moa community.

Abstract The present study aims to describe the occurrence of triatomines and their infection rate by Trypanosoma cruzi, in an area of Chagas disease outbreak in Rodrigues Alves municipality, Acre state, Brazil. Collections were performed by passive search (capture of specimens by local people) and dissection of palm trees (Attalea butyracea and Mauritia flexuosa). Thirty two triatomines belonging to four species grouped into two genera (Rhodnius and Eratyrus) had T. cruzi infection rate of 15.6%. Only in A. butyracea triatomines were captured. The passive search was the most effective method for collection. The Nova Cintra triatomine fauna comprises four species and it is important to carry out future studies to understand the biology of these triatomines.

Resumen El presente estudio tiene como objetivo describir la aparición de triatominos y la infección causada por Trypanosoma cruzi, en un área de brote de la enfermedad de Chagas en el municipio de Rodrigues Alves, estado de Acre, Brasil. Las recolecciones se realizaron mediante búsqueda pasiva y disección en palmeras (Attalea butyracea y Mauritia flexuosa). Treinta y dos triatominos pertenecientes a cuatro especies agrupadas en dos géneros (Rhodnius y Eratyrus) tenían una tasa de infección por T. cruzi del 15,6%. Solo en A. butyracea se capturaron triatominos. La búsqueda pasiva fue el método más efectivo para la recolección. La fauna triatomina de Nova Cintra comprende cuatro especies, es importante realizar futuros estudios para comprender su biología.

ABSTRACT The etiological agent of American trypanosomiasis is the protozoan Trypanosoma cruzi , typically transmitted by triatomines. The aim of this study was to investigate the triatomine fauna and trypanosomiasis infections in Acre State , Western Brazilian Amazon. Insect collection was performed by dissecting palm trees and installing traps. We found that T. cruzi infection rate was 24.5% and Rhodnius pictipes (57.1%) was the most abundant triatomine species. Health education as well as epidemiological and entomological surveillance are necessary to diagnose and prevent new cases of Chagas disease in the region.

Abstract Introduction: The genus Rhodnius in the subfamily Triatominae comprises 20 species, which can transmit Trypanosoma cruzi and Trypanosoma rangeli. Due to the development of molecular techniques, Triatominae species can now be characterized by mitochondrial and nuclear markers, making it possible to verify and/or correct the existing data on these species. The results achieved in this study provide a more detailed and accurate differentiation of the Rhodnius species, helping the establishment of a more appropriate classification. Methods: Data collection was performed by DNA analysis, morphological and morphometric studies to distinguish four populations of R. neglectus and four of R. prolixus. Phylogenetic data were compared to morphological and morphometric data. Results: The analysis of Cytb fragments suggests that the four colonies designated to Rhodnius neglectus as well as those of R. prolixus were correctly identified. Conclusions: The morphological characters observed in the specimens of the colonies originally identified as R. prolixus and R. neglectus, such as the presence or absence of collar in the eggs, the patterns of the median process of the pygophore, and anterolateral angle, are consistent with the species. Geometric morphometrics also show an intraspecific variability in R. prolixus.

Abstract INTRODUCTION: Triatomines are hematophagous insects of epidemiological importance because they are vectors of Chagas disease. We present here the first report of Rhodnius montenegrensis in Amazonas, Brazil. METHODS: Triatomines were collected from Attalea butyracea palm trees in the municipality of Guajará. RESULTS: Two adult female R. montenegrensis specimens were identified. CONCLUSIONS: The present study confirms that the number of triatomine species within the Amazon has increased from 10 to 11, and the number of Brazilian states with R. montenegrensis has increased from two to three.

Abstract INTRODUCTION: This study describes the occurrence of triatomines, and their positivity for trypanosomatids, in a residential complex in Rio Branco, Acre, Brazil. METHODS: Triatomines were collected through direct capture in a home environment. Positivity analysis for trypanosomatids was performed by PCR assays. RESULTS Collected insects consisted of 31 Rhodnius robustus, 4 Rhodnius montenegrensis, and 1 Panstrongylus geniculatus specimens. All were adults, with no presence of domiciliation, and with an infection rate of 30.6%. CONCLUSIONS Future studies are recommended in other locations of Rio Branco in order to develop a georeference database of the occurrence of triatomines in urban areas.