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Detecção molecular e análise filogenética de filarídeos em primatas Sapajus apella da região geográfica imediatada de Bacabal, Maranhão

2026-07-09T19:57:11Z

Título: Detecção molecular e análise filogenética de filarídeos em primatas Sapajus apella da região geográfica imediatada de Bacabal, Maranhão Abstact: Filarids are nematodes belonging to the superfamily Filarioidea, recognized for infecting various groups of vertebrates, including Neotropical primates. In Brazil, despite the wide distribution and diversity of species of the genus Sapajus, studies aimed at detecting these parasites in wild populations are still scarce. In Maranhão, particularly in the Immediate Region of Bacabal, an ecological transition area between biomes, with high biodiversity and interaction between wildlife and anthropogenic environments, no studies have yet been carried out on filarids in free-ranging Neotropical primates. In this context, the present study aimed to perform the molecular detection and phylogenetic characterization of filarids detected in Sapajus apella from the region. Between September 2024 and January 2025, individuals of the species S. apella were captured using Tomahawk traps. After restraint, blood samples were collected by puncture of the jugular or femoral vein. Part of the samples was used for the preparation of blood smears, stained by the panoptic method, while another fraction was used for genomic DNA extraction using the QIAamp DNA Mini Kit (QIAGEN®, Germany). The extracted DNA was amplified by Polymerase Chain Reaction (PCR) targeting the cox1, 18S, and 12S genes, followed by Sanger sequencing. The sequences obtained for the cox1 gene were analyzed by BLAST and used for phylogenetic inference by the Maximum Likelihood method. Drops of blood were added to LIT medium for Trypanosoma culture for a parallel project. Of the 14 individuals of S. apella analyzed, three (21.43%) individuals were positive with the presence of parasitic forms in blood smears. Regarding PCR, six (42.85%) samples were positive for the cox1, 18S, and 12S genes. All amplified samples were submitted to sequencing; however, for the cox1 gene, four of them (66.7%) presented adequate quality for analysis and were used in the construction of the phylogenetic tree. The sequences obtained showed identity between 96% and 99% with Dipetalonema gracile according to BLAST, clustering exclusively within the clade of the genus Dipetalonema. The results confirm the occurrence of filarids of the genus Dipetalonema in S. apella in Maranhão. This study represents the first record of the presence of this parasite in primates of this species in the state, expanding knowledge about the distribution of filarids in Neotropical primates in Brazil.

Epidemiologia molecular e caracterização de Leucocytozoon spp. em frangos caipiras na ilha de São Luís - MA

2026-07-09T17:27:11Z

Título: Epidemiologia molecular e caracterização de Leucocytozoon spp. em frangos caipiras na ilha de São Luís - MA Abstact: Subsistence poultry farming is an activity present in the life of rural communities in the state of Maranhão, having an important cultural and economic role. In domestic poultry breeding sites, it is common to witness the interaction and breeding of these animals with wild and migratory bird species. These aspects can favor the dispersion and occurrence of several infectious and parasitic agents, since these animals can act as potential biological carriers or mechanical transporters, allowing them to colonize new areas and parasitize susceptible hosts. Avian leukocytozoonosis is caused by protozoa of the genus Leucocytozoon spp. Its transmission occurs through the bite of dipteran insects, belonging to the Simuliidae and Ceratopogonidae families. Given the above, the objective of this work was to verify the occurrence of Leucocytozoon spp. in free-range chickens that live with migratory birds on the island of São Luís, Maranhão. 100 blood samples were collected from free-range chickens from the four municipalities that are part of the island of São Luís - MA. To identify the parasite, the Nested PCR technique was performed. However, of all the samples analyzed, none showed a positive result for Leucocytozoon spp. Although the presence of Leucocytozoon spp. has not been identified, future studies are needed to help determine the geographic distribution of the parasite, since the island of São Luís is part of the migratory route of coastal birds that can carry several pathogens, in order to avoid the occurrence of hemosporidian in subsistence poultry farms

Caracterização clínica, histológica e molecular da gengivite estomatite crônica felina

2026-07-07T16:09:29Z

Título: Caracterização clínica, histológica e molecular da gengivite estomatite crônica felina Abstact: Feline chronic gingivostomatitis (FCGS) is a severe inflammatory disease characterized by diffuse or focal ulcerative and/or proliferative lesions affecting the alveolar, lingual, and buccal mucosae. Its etiology is considered multifactorial, involving infectious, immunological, and environmental factors. Definitive diagnosis requires detailed anamnesis, thorough clinical examination, and complementary tests. The present study aimed to characterize oral lesions in 30 cats affected by FCGS through clinical, histological, and molecular analyses. Clinically, the disease was more frequent in young adult animals, accounting for 70%, and less common in geriatric individuals (10%). Among the clinical signs, halitosis was observed in all cases, while ptyalism, oral discomfort, and hyporexia occurred in 63.3% of the animals. Oral examination revealed ulcerative and proliferative lesions in all cats, affecting the pharynx, glossopalatine arch, gingival, alveolar, and buccal mucosae, often extending to the lateral base of the tongue. These lesions exhibited intense reddish coloration, friable consistency, and bleeding upon manipulation. Additionally, 100% , of the animals presented lesions compatible with tooth resorption. Histopathological analysis revealed inflammatory infiltrates predominantly composed of plasma cells and lymphocytes, epithelial hyperplasia, ulcerations, necrosis, and reparative areas characterized by granulation tissue and fibrosis. Diagnostic tests for FeLV and Leishmania spp. were negative in all animals, while three tested positive for FIV. The findings confirm the chronic nature of FCGS and demonstrate that, although it may be associated with immunosuppression, the disease does not rely exclusively on this condition for its manifestation.

Revisão sistemática e meta-análise da prevalência de Leishmania spp. em vetores da leishmaniose tegumentar americana no Brasil e mapeamento de áreas prioritárias para sua vigilância na região Nordeste do país

2026-07-06T19:31:07Z

Título: Revisão sistemática e meta-análise da prevalência de Leishmania spp. em vetores da leishmaniose tegumentar americana no Brasil e mapeamento de áreas prioritárias para sua vigilância na região Nordeste do país Abstact: American cutaneous leishmaniasis (ACL) is a neglected disease whose transmission involves complex interactions among different protozoan species of the genus Leishmania, sand fly vectors, and vertebrate hosts in diverse ecological settings. This dissertation is organized into an introductory chapter of general considerations, followed by two chapters written in the format of scientific articles, which investigate the ecology and epidemiology of ACL. The second chapter presents a systematic review and meta-analysis focusing on natural Leishmania spp. infection prevalence and blood meal sources of vectors in Brazil. Data from 71 studies were synthesized, revealing a pooled prevalence of 2.17% (n=52,315 specimens). The vectors of greatest epidemiological importance were Nyssomyia whitmani (3.54%) and N. umbratilis (1.71%), with the latter standing out as the main vector of L. (V.) guyanensis in the Amazon. N. whitmani demonstrated trophic and parasitic plasticity, with infection by different Leishmania species and an infection rate for L. (V.) braziliensis of 1.03%. Blood meal analysis revealed a high frequency of detection for animal groups commonly found in peridomestic settings, such as birds (35.75%) and humans (21.35%), suggesting vector interaction with anthropized environments. The third chapter focused on mapping ATL risk in Northeast Brazil (2013-2024), integrating ecological niche modeling, spatial autocorrelation analysis, and space-time scanning. The vector suitability model (AUC = 0.86 ± 0.02) identified precipitation of the coldest quarter as the main environmental determinant, with high suitability in eastern Maranhão, northern Piauí, and the Atlantic Forest coastal strip. Disease incidence showed strong positive spatial autocorrelation [Moran's (I) coefficient = 0.55; p < 0.05], forming High-High clusters concentrated in the states of Maranhão (58.1% of municipalities), Bahia (36.5%), and Ceará (13.5%). Space-time scanning detected 18 recent (2021-2024) high-risk clusters, with notable clusters in the states of Bahia [Relative Risk (RR) = 29.7] and Ceará (RR = 70.6). Bivariate LISA analysis demonstrated that high-incidence clusters spatially overlap areas of high forest cover (I = 0.32) and extreme social vulnerability, especially lack of urban infrastructure (I = 0.13) and low human capital (I = 0.09), with high concentration in Maranhão. The confluence of high vector suitability and high incidence identified priority municipalities for surveillance in Maranhão (40.4%) and Bahia (35.8%). In summary, these findings confirm that ACL transmission is driven by a combination of specific vector species with ecological plasticity and distinct epidemiological profiles, and spatially defined hotspots where environmental suitability converges with critical socioeconomic vulnerability. The identification of N. whitmani and N. umbratilis as key vectors, along with the precise mapping of priority areas in Maranhão, Bahia, and Ceará, provides support for the implementation of integrated surveillance and control strategies, focused on the municipalities and epidemiological scenarios with the highest identified risk.