https://orcid.org/0000-0002-2799-8267
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Figures
Abstract
This study investigated the diversity of trypanosomatids infecting small mammals in a fragmented forest landscape in southeastern Brazil, to gain insight into their role in transmission cycles and to assess potential public health risks. Eighteen small mammals were captured; seventeen were included in laboratory analyses: Didelphis albiventris (n = 4), Marmosops incanus (n = 4), and Nectomys squamipes (n = 9) were captured in the Mata da Tapera Municipal Natural Park, Minas Gerais State. To detect infection and assess host infectiousness, we used xenodiagnoses (Rhodnius neglectus and Lutzomyia longipalpis), 18S rRNA nested PCR, molecular typing, and parasitological culture. Leishmania infantum was identified in three individuals (two N. squamipes and one D. albiventris), L. braziliensis in one M. incanus, Trypanosoma cruzi DTU TcI in two D. albiventris, and T. lainsoni was detected in one D. albiventris and one N. squamipes. This integrated diagnostic strategy illustrates the value of combining parasitological, molecular, and experimental approaches for zoonotic surveillance at the wildlife-urban interface. Our findings document the occurrence of zoonotic trypanosomatids in a human-modified landscape and highlight potential transmission risks to humans and domestic animals, particularly in an area with active ecotourism, emphasizing the need for targeted surveillance within a One Health framework.
Author summary
In many parts of Brazil, forested areas are getting smaller and more fragmented due to urban growth. These changes increase the contact between wild animals, domestic animals, and humans, creating new opportunities for pathogen transmission. In this study, we examined small wild mammals living in a forest fragment close to human settlements in southeastern Brazil to find out if they carried parasites that can also infect humans. We used a combination of techniques, including allowing laboratory-raised sand flies and kissing bugs (triatomines) to feed on the animals, to detect the presence of parasites and assess whether they could be detected in vectors after blood feeding. We found that these mammals were naturally infected with species of Leishmania and Trypanosoma, including those that cause leishmaniasis and Chagas disease in humans. We also detected Trypanosoma lainsoni, a lesser-known parasite, for the first time in Nectomys squamipes. Our findings suggest that small mammals living in areas where forests meet cities may play an important role in maintaining and spreading parasites that affect public health. Although the number of animals examined was limited, the detection of multiple zoonotic parasites in this small sample underscores how even small fragments at the wildlife-urban interface can sustain complex assemblages of zoonotic parasites and potential transmission cycles.
Citation: Madureira ACC, Isnard AP, Lima ACVMdR, Capucci DC, Martins ALM, Estevam LGTdM, et al. (2026) Zoonotic trypanosomatids in small mammals at a wildlife-urban interface in southeastern Brazil: Implications for transmission risk. PLoS Negl Trop Dis 20(3): e0013455. https://doi.org/10.1371/journal.pntd.0013455
Editor: Brice Rotureau, Institut Pasteur, FRANCE
Received: August 7, 2025; Accepted: March 7, 2026; Published: March 13, 2026
Copyright: © 2026 Madureira et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Data Availability: All sequence data generated in this study are publicly available in GenBank (accession numbers PV688719–PV688727). All raw diagnostic data underlying the findings of this study, including xenodiagnosis outcomes, parasitological culture results, and tissue-based PCR data, are provided as Supporting information (S1 File). No additional data are required to reproduce the results reported in this manuscript.
Funding: This study was supported by the Young Talents Program of Fiocruz Minas (Instituto René Rachou, Fundação Oswaldo Cruz), Brazil (grant number: PJT 2022-2025), awarded to FDR (Felipe Dutra-Rêgo). The funder’s website is available at: https://minas.fiocruz.br/ The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing interests: The authors have declared that no competing interests exist.
Introduction
Habitat fragmentation, urban expansion, and increasing human-wildlife contact are reshaping host–parasite dynamics worldwide [1,2]. Forest disturbance and fragmentation can lead to habitat loss and changes in blood meal availability for vectors, emerging as critical drivers in the transmission dynamics of leishmaniasis and Chagas disease [3,4]. Transitional zones between wild and urban environments are often subject to biodiversity loss, favoring generalist species, such as rodents and marsupials, that can act as pathogen reservoirs [5–7]. These ecological shifts intensify interactions among humans, domestic animals, and wildlife, creating favorable conditions for spillover (wildlife-to-human transmission) and spillback (human-to-wildlife transmission) [4].
In southeastern Brazil, where rapid urban expansion overlaps remnants of the Atlantic Forest and Cerrado biomes [8,9], peri-urban forest fragments represent key ecological interfaces between human settlements and wildlife. In these transitional landscapes, synanthropic mammals, particularly rodents and marsupials, serve as both reservoirs and sentinels for a broad diversity of trypanosomatids, from non-pathogenic to medically important species. These hosts may contribute to parasite amplification across heterogeneous environments and sustain transmission cycles that are often overlooked due to the cryptic nature of host-parasite associations [10–12].
Despite their potential role in maintaining parasite circulation, the structure of host-parasite interactions and their ability to sustain enzootic or zoonotic cycles in disturbed peri-urban forests remain insufficiently understood. While classical transmission areas have been extensively studied, fewer investigations have focused on transitional landscapes subjected to intense anthropogenic pressure [6,13].
Here, we investigated the diversity of trypanosomatids infecting small mammals in a forest fragment located at the wildlife-urban interface in southeastern Brazil. This region has previously reported autochthonous cases of canine visceral leishmaniasis (Health Department of Minas Gerais), and phlebotomine sand flies carrying Leishmania DNA have also been recorded [14]. In addition, Panstrongylus megistus, one of the primary vectors of Chagas disease in Brazil, is also present in the area, supporting the plausibility of enzootic transmission cycles in the area [15,16]. By characterizing infections in small mammals and assessing their potential to infect known vector species, we provide insights into the ecological dynamics of trypanosomatid transmission in transitional environments. Our findings highlight that small mammal communities can act as hosts within complex transmission networks and underscore the potential epidemiological implications of parasite occurrence in areas under increasing anthropogenic pressure.
Materials and methods
Ethical statements
This study was approved by the Animal Ethics Committee (CEUA - Comissão de Ética no Uso de Animais) of the Oswaldo Cruz Foundation (protocol number LW-3/23) and authorized by the Authorization and Information on Biodiversity System (SISBIO; permit number 86644–1). The collection of biological material from mammals and access to genetic resources were conducted in compliance with Brazilian regulations. The study was registered in the National System for the Management of Genetic Heritage and Associated Traditional Knowledge (SisGen) under registration number A47F256.
Study area and sample collection
The Mata da Tapera Municipal Natural Park (MT), located in the Serra do Cipó district of Minas Gerais State (19° 19’ 58.7“ S 43° 36’ 52.5” W), is part of a network of protected areas known as the “Cipó Mosaic”, a UNESCO-recognized site and part of the Espinhaço Range Biosphere Reserve. The park covers 31.3 hectares (0.313 km²) and is situated entirely within the urban perimeter. Although it is a highly human-modified (anthropized) forest fragment with close interactions among humans, domestic animals, and wildlife, the park holds significant socio-environmental value due to its natural springs and remnants of the Brazilian Cerrado.
Between March 2023 and September 2024, six small mammal sampling campaigns were conducted in the MT area (Fig 1), covering both the rainy (n = 2) and dry (n = 4) seasons. Sampling was restricted to accessible trails, which may overrepresent edge-associated species. A total of 160 galvanized steel Tomahawk traps (40 per trail) were deployed during each campaign and baited with a mixture of fruit and cod liver oil emulsion or bacon. Specimens were identified following the taxonomic keys proposed for Brazilian mammals [17,18], and all specimens were deposited in the Mammal Collection of the Natural Sciences Museum, Pontifical Catholic University of Minas Gerais (PUC-Minas).
(A) General view of the MT area, showing its proximity to peridomestic environments. (B) Steel traps (Tomahawk model) baited with a mixture of fruit and cod liver oil emulsion or bacon, used for small mammal captures. Image provided by the authors and published under a CC BY license.
Following species identification, animals were anesthetized with a combination of xylazine (10 mg/kg) and ketamine (20 mg/kg) for xenodiagnoses and intracardiac blood collection. Euthanasia was then performed by anesthetic overdose to allow macroscopic inspection of the skin for cutaneous lesions and the collection of organs and tissues for parasitological culture and molecular detection of trypanosomatids.
Host infectiousness to vectors
Anesthetized small mammals were positioned in dorsal recumbency for xenodiagnoses procedures using laboratory-reared L. longipalpis (Piauí, Brazil), obtained from the phlebotomine sand fly colony maintained at the Laboratory of Physiology of Hematophagous Insects, Federal University of Minas Gerais (UFMG), and Rhodnius neglectus (Tocantinópolis, Tocantins, Brazil), from the triatomine colony of the René Rachou Institute, Oswaldo Cruz Foundation (Fiocruz Minas). Insects were placed in ventilated plastic containers covered with permeable mesh and positioned over the abdominal region and limbs of the animals to allow blood feeding for approximately 30 minutes (Fig 2).
(A) Nectomys squamipes under anesthesia during xenodiagnoses with Lutzomyia longipalpis. (B) Fourth-instar nymphs of R. neglectus used in the procedure. Animals were maintained under sedation with xylazine (10 mg/kg) and ketamine (20 mg/kg) for approximately 30 minutes during xenodiagnostic exposure.
For each mammal, 100 female and 20 male L. longipalpis were used. Males were included to provide pheromonal cues and promote aggregation and blood feeding of females. After feeding, engorged sand flies were transferred to insulated containers with continuous monitoring of temperature and humidity (25 °C, 80% RH) and maintained in the insectary of the Medical Entomology Group at IRR/Fiocruz Minas. Sand flies were provided with a 15% glucose solution ad libitum during the holding period. Specimens were euthanized five days post-feeding and processed for molecular detection and identification of Leishmania spp. via 18S rRNA nested PCR and sequencing, as described below.
For triatomines, 10 third- or fourth-instar nymphs of R. neglectus were used per mammal, in accordance with the method described in the literature [19]. Nymphs were maintained in an incubator under controlled conditions (27 °C, 60% RH, 12:12 h light/dark cycle) and were fed on chicken blood 10 days after xenodiagnoses. Infectivity was assessed 30 days post-exposure by parasitological examination. Feces were obtained by gentle abdominal compression, placed on a microscope slide with a drop of 1 × PBS, covered with a coverslip, and examined under a binocular light microscope at 400 × magnification. All visual fields were systematically screened for the presence of Trypanosoma spp.
Parasitological isolation of trypanosomatids from blood and tissues
Whole blood aliquots were immediately inoculated in the field into biphasic NNN/LIT culture medium. Tissue fragments (ear skin, tail skin, heart, spleen, and liver) were stored at 4 °C for 72 hours in phosphate-buffered saline (PBS 1 × , pH 7.2), supplemented with antibiotics (penicillin, 5,000 U/mL; streptomycin, 5,000 µg/mL) and an antifungal agent (5-fluorocytosine, 50 mg/L). After homogenization under a laminar flow hood, tissues were inoculated into biphasic NNN/LIT medium supplemented with 20% sterile, heat-inactivated fetal bovine serum and antibiotics, as previously described.
Cultures were maintained in individually labeled 15 mL conical tubes and incubated at 25 °C (±1 °C). Each culture was examined weekly under light microscopy for the presence of flagellated forms and subcultured into fresh medium as needed, for up to three months. Cultures exhibiting fungal or bacterial contamination were discarded based on macroscopic and microscopic evaluation. Positive cultures were centrifuged at 2,500 × g for 10 minutes, and the resulting parasite pellet was subjected to DNA extraction using the Gentra Puregene Tissue Kit (Qiagen), followed by molecular identification using 18S rRNA nested PCR and sequencing, as described below.
DNA extraction and endogenous controls
Fragments of ear skin, tail skin, heart, spleen, liver, lung, intestine, lymph nodes, and whole blood were collected for molecular diagnostics. All samples were individually labeled, preserved in RNAlater (Invitrogen), and stored at -20 °C until DNA extraction. Total DNA was extracted using the Gentra Puregene Tissue Kit (Qiagen), following the manufacturer’s instructions, and eluted in 50 µL of elution buffer.
To assess DNA integrity and detect potential PCR inhibitors, different endogenous controls were selected according to sample type. Whole blood samples were subjected to amplification of the vertebrate mitochondrial cytochrome b gene using primers cytb1 (5′-CCATCCAACATCTCAGCATGATGAAA-3′) and cytb2 (5′-GCCCCTCAGAATGATATTTGTCCTCA-3′) [20], due to the higher copy number of mitochondrial DNA and its increased sensitivity in samples potentially containing low amounts of host nuclear DNA. For tissue and organ samples, DNA quality was evaluated by amplifying a 70 bp fragment of the mammalian γ-actin gene using primers γactin-For (5′-ACAGAGAGAAGATGACGCAGATAATG-3′) and γactin-Rev (5′-GCCTGAATGGCCACGTACA-3′) [21], which serves as a nuclear DNA integrity control.
Molecular identification of trypanosomatids was subsequently performed using nested 18S rRNA PCR and sequencing, as described below.
Molecular identification of trypanosomatids
Trypanosomatid detection and identification were performed using a nested PCR targeting the V7-V8 variable region of the 18S rRNA gene [22,23]. This approach was applied to DNA extracted from (i) sand flies following xenodiagnoses, (ii) parasite isolates obtained through in vitro culture, and (iii) mammalian blood, tissues, and organs.
Each PCR assay included a negative control (no DNA template) and positive controls containing 10 ng of DNA from L. amazonensis (IFLA/BR/67/PH8) and Trypanosoma cruzi (DTU TcI).
PCR products were purified using the QIAquick PCR Purification Kit (Qiagen) and subjected to bidirectional Sanger sequencing. Electropherograms were manually inspected using FinchTV to assess peak quality and confirm base calls. Forward and reverse reads were assembled into consensus sequences by retaining only nucleotides with Phred quality scores ≥30. Ambiguous positions were verified through chromatogram inspection, and IUPAC ambiguity codes were assigned when appropriate. Primer-derived nucleotides were trimmed prior to downstream analyses.
High-quality consensus sequences were queried against the NCBI nucleotide database using BLAST to obtain preliminary taxonomic identification. All sequences generated in this study were deposited in GenBank under accession numbers PV688719-PV688727.
Phylogenetic analysis
Phylogenetic inference was performed using sequences generated in this study together with reference sequences obtained from GenBank, selected based on BLAST similarity searches and taxonomic representation within Leishmaniinae and Trypanosomatinae. The 18S rRNA V7-V8 region was aligned in MAFFT v7.505 using the E-INS-i algorithm [24] followed by automated trimming with trimAl v1.5 (gap threshold = 0.5) to remove ambiguously aligned sites [25]. Maximum Likelihood (ML) trees were inferred in IQ-TREE v2.4.0 [26], and the best-fit substitution model was selected separately for each dataset using ModelFinder [27]. Node support was assessed through 1,000 SH-aLRT and 1,000 ultrafast bootstrap replicates [28].
For the Leishmania spp. dataset, the tree was rooted using Leptomonas pyrrhocoris as a close external outgroup. For the Trypanosoma spp. dataset, the tree was rooted using Leishmania braziliensis as an external outgroup to ensure appropriate rooting.
Results
A total of 18 small mammals were captured, representing three species: Nectomys squamipes (n = 9; 50%), Didelphis albiventris (n = 5; 27.8%), and Marmosops incanus (n = 4; 22.2%). Of 18 captured mammals, one was released and two died before xenodiagnoses, resulting in 15 individuals subjected to vector exposure. No cutaneous lesions were observed during clinical examination of any individual in the field.
Most captures occurred during the dry season (n = 14; 77.7%), reflecting the distribution of sampling campaigns across the period (Table 1).
Overall, 150 triatomines were examined under a light microscope. All nymphs exposed to animal ID02 tested positive for Trypanosoma sp. (n = 10), whereas only two out of ten nymphs were positive for D. albiventris ID16.
A total of 102 biological samples, including ear skin, tail skin, spleen, liver, heart, and blood, from 17 individuals were subjected to parasitological culture. Of these, 39 samples (38.2%) were discarded due to contamination, and 60 (58.8%) were negative after three months of monitoring. Trypanosomatids were isolated from 3/102 blood samples (2.9%): two from D. albiventris and one from N. squamipes. Species identification based on 18S rRNA sequencing revealed T. cruzi in one D. albiventris individual (ID16) and T. lainsoni in both D. albiventris (ID02) and N. squamipes (ID09) (Table 2; Fig 4).
Node support is shown as SH-aLRT (%)/ ultrafast bootstrap (UFBoot, %) based on 1,000 replicates. The best-fit model selected by ModelFinder was HKY. The tree was rooted using Leptomonas pyrrhocoris as outgroup. Sequences generated in this study are highlighted in red.
Node support is shown as SH-aLRT (%)/ ultrafast bootstrap (UFBoot, %) based on 1,000 replicates. The best-fit model selected by ModelFinder was TN + F + G4. The tree was rooted with Leishmania braziliensis as outgroup. Sequences generated in this study are highlighted in red.
Two individuals exhibited confirmed mixed infections supported by complementary diagnostic approaches. ID02 (D. albiventris) harbored both T. cruzi, detected in blood and lymph node samples, and T. lainsoni, identified by parasitological culture of blood and PCR from a tail skin fragment. ID09 (N. squamipes) was co-infected with L. infantum, detected through xenodiagnoses followed by PCR of fed sand flies, and T. lainsoni, isolated from blood culture.
All raw diagnostic outcomes from xenodiagnoses, parasitological culture, and tissue-based PCR analyses are provided in Supplementary S1 File.
Discussion
The proximity of MT to neighboring residential areas facilitates interactions between humans, domestic animals, and wildlife across natural and urbanized interfaces. In fragmented landscapes, common in urban settings, resource scarcity can reduce the viability of larger wildlife populations, leading to biodiversity loss and shifts in host and vector communities [5]. Such environments tend to favor synanthropic species, such as D. albiventris, and those with restricted home ranges, like N. squamipes and M. incanus [29,30]. Habitat edges intensify contacts between humans, vectors, and wildlife, increasing the likelihood of zoonotic protozoa circulation, particularly multi-host pathogens such as Leishmania spp. and T. cruzi [4]. In this study, six of the 17 small mammals examined in the laboratory (35.3%) were naturally infected with trypanosomatids, including individuals of all three species captured. These findings indicate that small mammals are exposed to, and may transiently harbor, zoonotic parasites at the wildlife-urban interface; however, given the reduced number of captured individuals and the absence of parallel vector sampling in this study, inferences regarding reservoir competence or sustained maintenance of transmission cycles in the study area must remain conservative.
Leishmania infantum, the etiological agent of visceral leishmaniasis (VL) in Brazil, is primarily transmitted by Lutzomyia longipalpis [31]. Although Lu. longipalpis is the main vector, Pintomyia fischeri and Migonemyia migonei have been also identified in neighboring areas such as Jaboticatubas and may act as secondary vectors [14]. Detection of L. infantum in three small mammals (11.76%), one D. albiventris and two N. squamipes, suggests that these species may serve as alternative hosts, despite the traditional role of domestic dogs as the principal urban reservoirs of VL. Natural infections in D. albiventris have been documented in different regions [5,32,33], reinforcing its relevance at the wildlife-urban interface.
Infection by L. braziliensis was detected exclusively through xenodiagnoses in M. incanus. Unlike L. infantum, typically associated with canids, L. braziliensis is more frequently found in hosts from the orders Xenarthra and Rodentia [32]. Previous studies in the Serra do Cipó region identified Ny. whitmani carrying L. braziliensis and L. infantum DNA [14], and in other parts of Minas Gerais, carrying L. guyanensis [12], suggesting a broader role in sylvatic cycles of multiple Leishmania species.
Although PCR detection in Lu. longipalpis five days post-feeding is compatible with parasite development beyond bloodmeal digestion [34], PCR positivity alone does not distinguish early promastigote stages from fully differentiated metacyclic forms. Low infection rates in sand flies likely reflect the low parasitemia observed in naturally infected mammals. In addition, xenodiagnoses detects only the parasites that are successfully acquired and able to initiate development in the vector. Demonstrating transmissibility would require additional analyses targeting markers of metacyclogenesis, such as sherp gene expression by RT-qPCR or direct detection of metacyclic promastigotes in the anterior midgut [35]. Because these evaluations were beyond the scope of the present study, transmissibility remains undetermined, a common limitation in studies employing xenodiagnoses as a proxy for host infectiousness.
Trypanosoma cruzi infection (DTU TcI confirmed by molecular analysis) was detected in two D. albiventris individuals. Microscopic observation of flagellates in triatomines following xenodiagnoses suggests host infectiousness for Trypanosoma sp., while species identification was confirmed by PCR and sequencing of the parasites isolated from blood or tissues. Marsupials of the order Didelphimorphia are recognized for their high infectivity to T. cruzi, particularly DTU TcI, across a wide range of ecological settings throughout the Americas [36,37]. Rodents also exhibit high susceptibility and parasitemia levels, contributing as secondary reservoirs [38]. The DTU TcI identified here is the most widespread lineage in the Americas and is frequently associated with sylvatic transmission cycles involving Rhodnius spp., particularly in arboreal ecotopes, although it also participates in domestic transmission in several regions [39]. Although R. neglectus was used in xenodiagnoses, field-collected specimens of Panstrongylus megistus, a well-documented T. cruzi vector in Minas Gerais, were found near palm trees in the MT area [15,16], reinforcing the need to investigate its infection status in the study area.
Trypanosoma lainsoni, with no known pathogenicity to humans, remains poorly characterized [40,41]. Initially assigned to the “Megatrypanum” group, it has recently been placed within the LSRM clade, which includes parasites infecting reptiles, rodents, and marsupials [42]. Here we report the first natural infection of N. squamipes by T. lainsoni, expanding its known host range. To date, no natural vector has been confirmed for this species. However, related taxa such as T. (Squamatrypanum) gennarii have been experimentally maintained in insect cell culture systems, providing indirect evidence of an evolutionary association with hematophagous Diptera [43]. The absence of T. lainsoni in both R. neglectus and L. longipalpis in our xenodiagnoses may reflect a degree of vector incompatibility or low parasitemia and limited parasite acquisition, although this remains inconclusive. Alternative transmission pathways, including oral transmission during grooming or ingestion of infected tissues, should be considered as plausible mechanisms for parasite maintenance in wildlife.
Among the positive mammals, only one individual (D. albiventris, ID16) tested positive for the same parasite (T. cruzi) by all diagnostic approaches (culture and direct PCR, both confirmed by 18S rRNA sequencing). In contrast, Leishmania infections were identified exclusively through xenodiagnoses, likely due to low parasitemia. Under such conditions, sand fly infection followed by early parasite development, amplified by euthanizing insects five days post-feeding, may enhance detectability [34]. Furthermore, subsequent PCR targeting 18S rRNA gene increased sensitivity. While low parasitemia may limit the effectiveness of direct parasitological or molecular methods, it may still suffice for vector infection and transmission in nature. Molecular tools offer high sensitivity and specificity, while culture permits the isolation of viable parasites, and xenodiagnoses provides insights into host infectiousness [44].
Nonetheless, some limitations must be acknowledged. First, the limited sample size and representation of only three small mammal species restrict ecological inference and likely underestimate the diversity of trypanosomatids in the MT area. However, trypanosomatid infection was detected in 35.3% of the sampled individuals, indicating substantial parasite occurrence in this highly fragmented and anthropized environment. Second, xenodiagnoses selectively detects parasites capable of infecting and developing in the tested vectors, potentially missing taxa with different ecological or developmental requirements. Third, culture-based parasite detection showed 38% contamination, which further limits parasite recovery and likely underestimates true infection rates, particularly for strains sensitive to in vitro conditions or present at low abundance. However, contamination rates were similar to those reported in other studies targeting trypanosomatid isolation in culture media [10,45]. Additionally, molecular identification was based on Sanger sequencing of 18S amplicons, which may have limited sensitivity for detecting mixed infections, as minority sequence variants can be masked by dominant templates in chromatogram reads. Consequently, co-infections may be underestimated, and future studies employing high-throughput sequencing approaches could provide a higher-resolution assessment of parasite diversity within individual hosts.
The detection of L. infantum, L. braziliensis, T. cruzi (DTU TcI), and T. lainsoni in small mammals from MT highlights the occurrence of multiple trypanosomatid species circulating within a highly fragmented peri-urban forest environment. Although the present findings are based on a limited number of hosts and do not allow robust inferences regarding reservoir competence or the long-term maintenance of transmission cycles, they provide evidence that small mammals inhabiting wildlife-urban interfaces are exposed to, and can harbor, zoonotic trypanosomatids of public health relevance. Similar ecotones, characterized by synanthropic small mammals, domestic animals, and competent vectors, are increasingly common in endemic regions undergoing rapid environmental change. By combining parasitological, molecular, and experimental diagnostic approaches, this study contributes baseline information for surveillance in anthropized landscapes, where ecological disturbance, human encroachment, and ecotourism may increase opportunities for pathogen spillover. Future studies integrating larger host sample sizes, vector infection data, and domestic animal surveillance will be essential to clarify the epidemiological roles of different host species and to better inform One Health-oriented control strategies, highlighting the importance of integrated surveillance in periurban ecotourism areas.
Supporting information
S1 File. Raw dataset of small mammal sampling and parasitological and molecular analyses.
This spreadsheet contains individual-level data on captured small mammals, including species identification, sampling locality, sex, and capture date, as well as results from xenodiagnoses, parasite culture, and nested PCR assays used to detect trypanosomatid infections.
https://doi.org/10.1371/journal.pntd.0013455.s001
(XLSX)
Acknowledgments
To the Fiocruz Network of Technological Platforms at Instituto René Rachou - Fiocruz Minas for the DNA sequencing facility, and their assistance and DNA sequencing services.
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