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Chagas disease, a neglected global health concern primarily transmitted through the bite and feces of kissing bugs, has garnered increasing attention due to recent outbreaks in northern Brazil, highlighting the role of oral transmission facilitated by the kissing bugs species Rhodnius robustus and Rhodnius pictipes. These vectors are associated with palm trees with large crowns, such as the maripa palm (Attalea maripa) and moriche palm (Mauritia flexuosa). In this study, we employ maximum entropy (MaxEnt) ecological niche models to analyze the spatial distribution of these vectors and palm species, predicting current and future climate suitability. Our models indicate broader potential habitats than documented occurrences, with high suitability in northern South America, southern Central America, central Africa, and southeast Asia. Projections suggest increased climate suitability by 2040, followed by a reduction by 2080. This study identifies present and future areas suitable for kissing bugs and palm tree species due to climate change, aiding in the design of prevention and management strategies., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Raul Narciso Carvalho Guedes reports financial support was provided by Conselho Nacional de Desenvolvimento Científico e Tecnológico. Raul Narciso Carvalho Guedes reports a relationship with National Council of Scientific and Tecnological Development (CNPq) that includes: funding grants. Raul Narciso Carvalho Guedes reports a relationship with Coordination of Higher Education Personnel Improvement that includes: funding grants. Raul Narciso Carvalho Guedes reports a relationship with Minas Gerais State Foundation of Support to the Research that includes: funding grants. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The state of Rondônia in the Brazilian Amazon is prone to diseases transmitted by insect vectors because of the environmental and population changes resulting from large hydroelectric projects and the expansion of agricultural and livestock industries. The first case of Chagas disease by vectorial transmission was recorded in 2019 in a rural area in Rondônia, reinforcing the need for entomological surveillance. Hence, our goal was to estimate the abundance of Rhodnius spp. in palm trees located in rural and periurban areas and in Brazil-Bolivia border regions, perform domiciliary searches, and check for possible associations between triatomines and the presence/absence of palm-inhabiting fauna and outdoor farming, domestic animals, and buildings. The sampling took place in five municipalities of Rondônia in 2014 (June to August) and 2015 (April to June). Triatomines were collected by active searches during the selective pruning of palm tree crowns. Domiciliary inspections lasted from 30 to 60 min. A set of captured triatomines was analyzed for Trypanosoma cruzi and T. rangeli infection by PCR. Overall, 496 insects were captured during sampling of 150 palms in rural areas and 150 in periurban areas. No triatomine was found during active searches of 59 dwelling either indoors or outdoors. The majority of triatomines caught in the palm trees were identified as Rhodnius robustus (98.6%), and seven specimens were R. pictipes. Triatomine infestation was observed in only 20% of the sampled palms (61/300) in the vicinity of 26/59 households. Nearly half of the infested palm trees had only one or two triatomines, and few palms presented more than 15 triatomines. The municipality of Buritis had the highest triatomine abundance and percentage of infested palms; however, the highest triatomine density per infested palm was observed in Alvorada D'Oeste, where a quarter of the palms were infested. Ants, arachnids, termites, reptiles, and rodents were frequently found in palm trees. Dogs were the predominant domestic animals in households, whereas hens and cattle were the main farming animals. Model estimates showed that the number of triatomines was affected by the presence of henhouses and varied strongly between localities. No relationships were detected between the average number of triatomines and palm fauna and/or palm height. Overall, approximately half of the triatomines were infected with T. cruzi (51.4%) and/or T. rangeli (47.2%), reinforcing the need for continuous entomological surveillance and implementation of community-based approaches because the Brazilian state of Rondônia borders areas experiencing reinfestation by domiciled species and potential colonization of animal shelters by triatomines., (Copyright © 2021. Published by Elsevier B.V.)

Chagas disease is a zoonosis that affects several million people and is caused by the parasite Trypanosoma cruzi, which is mainly transmitted through the feces of triatomine bugs. Within triatomines, several Rhodnius species have been found inhabiting palms, and certain factors such as palm species and location have been related to the abundance and T. cruzi infection of those insects in palms. In this study, the main goal was to determine if R. prolixus abundances and infection rates in Attalea butyracea and Elaeis guineensis palms are related to ecological factors such as palm species, crown microclimate, and available blood meal sources. Triatomine sampling was performed in two municipalities of Casanare, Colombia, specifically in the intersection of riparian forests and oil palm plantations. For R. prolixus abundance per palm, the predictors showing more relationship were palm species and blood meal species identified in the palm, and for T. cruzi infection per triatomine, they were palm species and nymphal stage. Palm microclimate was very similar in both palm species and did not show a relationship with triatomine abundance. Comparing palm species, A. butyracea showed more blood meal species, including more refractory host species, than E. guineensis, but lower T. cruzi infection rate and parasitaemia. Interestingly, non-arboreal blood meal species were frequently found in the analyzed nymphs, indicating that the blood source for R. prolixus in palms corresponded to all the fauna located in the surrounded landscape and not only in the palm. These results could expose a new ecological scenario to interpret the T. cruzi transmission in sylvatic environments., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Palms 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. Understanding and predicting triatomine-palm associations and palm infestation probabilities is important for enhancing Chagas disease prevention in areas where palm-associated vectors transmit T. cruzi. We present a comprehensive overview of palm infestation by triatomines in the Americas, combining a thorough reanalysis of our published and unpublished records with an in-depth review of the literature. We use site-occupancy modeling (SOM) to examine infestation in 3590 palms sampled with non-destructive methods, and standard statistics to describe and compare infestation in 2940 palms sampled by felling-and-dissection. Thirty-eight palm species (18 genera) have been reported to be infested by ∼39 triatomine species (10 genera) from the USA to Argentina. Overall infestation varied from 49.1-55.3% (SOM) to 62.6-66.1% (dissection), with important heterogeneities among sub-regions and particularly among palm species. Large palms with complex crowns (e.g., Attalea butyracea, Acrocomia aculeata) and some medium-crowned palms (e.g., Copernicia, Butia) are often infested; in slender, small-crowned palms (e.g., Euterpe) triatomines associate with vertebrate nests. Palm infestation tends to be higher in rural settings, but urban palms can also be infested. Most Rhodnius species are probably true palm specialists, whereas Psammolestes, Eratyrus, Cavernicola, Panstrongylus, Triatoma, Alberprosenia, and some Bolboderini seem to use palms opportunistically. Palms provide extensive habitat for enzootic T. cruzi cycles and a critical link between wild cycles and transmission to humans. Unless effective means to reduce contact between people and palm-living triatomines are devised, palms will contribute to maintaining long-term and widespread, albeit possibly low-intensity, transmission of human Chagas disease., (Copyright © 2015 Elsevier B.V. All rights reserved.)

After several public notifications of domiciliary invasions, palm trees were investigated in downtown Monte Alto City, São Paulo State, Brazil, in proximity to the city hall building, the main church, condominiums and marketing establishments. One hundred seventy four palm trees of 10 species were investigated, in which 72 specimens of Rhodnius neglectus, a potential Chagas disease vector, were captured via manual methods. All insects were collected from dead leaves, organic debris and bird nests in the only three Livistona australis palm trees in the central park square. This was the first record of R. neglectus colonizing this palm species. Although no Trypanosoma cruzi was found by abdominal compression followed by light microscopy, the poor nutritional status of the bugs hampered the examination of gut contents for parasite detection. Furthermore, the central crowns of the trees, which shelter bats (Chiroptera: Mammalia), could not be carefully searched for insects due to difficult access. This new finding highlights the sudden alteration in insect behavior, probably as a result of man's interference. This report aims to warn those involved in the health system about this new threat, justifying detailed research of the area to evaluate the magnitude of this emerging public health issue., (Copyright © 2013 Elsevier B.V. All rights reserved.)

To determine the infestation and trypanosome infection of triatomines captured in Mauritia flexuosa palm trees across its geographic distribution in the Brazilian savanna (Cerrado), we sampled 42 localities in eight states and in the Federal District, Brazil, between July 2005 and January 2010. Overall, 2154 specimens of the species Rhodnius neglectus, Psammolestes tertius, Triatoma sordida, and Microtriatoma borbai, were collected. Among the 341 palms sampled, 182 (53.3%) were infested with R. neglectus, which resulted in the capture of 1639 specimens (9.0 insects per infested palm). P. tertius occurred in 26 palms (8%), which resulted in the capture of 484 specimens (19 insects per infested palm). T. sordida (n=30) and M. borbai (n=1) occurred in only one location. From 537 R. neglectus examined, 44 were infected (8%) with Trypanosoma rangeli and/or Trypanosoma cruzi (Tc Id). M. flexuosa was previously recognized as a suitable breeding ecotope for R. neglectus in the Brazilian states of Minas Gerais, Goiás, Tocantins and the Federal District. Our results expand this distribution to other states (São Paulo, Bahia, Mato Grosso, Maranhão and Piauí), and also show that this particular palm tree harbors other triatomine species. Finally, we show that R. neglectus plays an important role in maintaining the enzootic circulation of T. cruzi and T. rangeli in the Brazilian savanna., (Copyright © 2011 Elsevier B.V. All rights reserved.)