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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

2026-01-29T00:00:00Z

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.

Caracterização morfológica dos metazoários parasitas de serrasalmus rhombeus, “piranha preta” (characiformes: serrasalmidae) oriundos do rio pericumã, no município de Pinheiro, Maranhão, Brasil.

2025-04-16T00:00:00Z

Título: Caracterização morfológica dos metazoários parasitas de serrasalmus rhombeus, “piranha preta” (characiformes: serrasalmidae) oriundos do rio pericumã, no município de Pinheiro, Maranhão, Brasil. Abstact: In the Baixada Maranhense, fish is an essential part of the population's diet, and local communities live off artisanal fishing to generate income and support their families. Among the fish consumed in this region, Serrasalmus rhombeus (Linnaeus, 1766), popularly known as the “black piranha”, belongs to the Serrasalmidae family and the Characiformes order, and is widely distributed in South America. Fish are the group of vertebrates with the greatest predisposition to parasitism, due to intrinsic factors in the aquatic environment, such as: excess carbon dioxide, ammonia and nitrite; low concentration of dissolved oxygen; accumulation of organic matter, as well as the easy dispersal of parasite eggs and larvae in the water, stimulating stress and immunosuppression in the animals' bodies. In the municipalities of Baixada Maranhense, fish is sold in open-air fairs and municipal markets, spaces that generally do not have adequate infrastructure for the sale of food of animal origin, due to poor hygiene conditions, lack of refrigeration and exposure to dust and insects. Fish meat from these municipalities, which have irregular sanitary inspections, can contain parasites embedded in the muscles or lodged in the viscera, affecting the health of consumers, especially when raw or undercooked fish is eaten. Food-borne parasitic diseases represent a major health risk, especially in underdeveloped countries such as Brazil. This study is characterized as descriptive and exploratory, quantitative in nature, with the aim of investigating the parasitofauna of Serrasalmus rhombeus in the Baixada Maranhense region. The sample consisted of 151 specimens of S. rhombeus, collected directly from the Pericumã River (Pinheiro-MA) by local fishermen using gillnets and a motorized canoe. The specimens were collected three times in two seasons, rainy and dry. In the first collection, 50 fish (adults) were obtained, with a total of 100 samples of gills and viscera; in the second, 18 fish (adults) with 36 samples; and in the third, 83 fish (24 adults and 59 juveniles), with 166 samples. All the fish available after fishing were chosen, and none of them had damaged biological material. In this study, Contracaecum sp was the only endoparasite found in S. rhombeus in the rainy and dry seasons, with temporal differences in prevalence and abundance. The average intensity was 6.2 in the rainy season; 7.91 in the 1st collection of the dry season, and 11.64 in the 2nd collection. The average abundance was 3.72 in the rainy season, and 5.2 and 2.38 in the dry season. With regard to parasitism by ectoparasites, monogeneans of the genera Anacanthorus sp, Amphitecium sp and Notozothecium sp were identified, with the species Anacanthorus amazonicus having the highest prevalence. Knowledge of the parasitofauna of S. rhombeus in the Pericumã basin was important for understanding the biological aspects of the host, such as its position in the food chain, as well as the zoonotic potential of the parasites and the conditions of the environment in which they live.

Aspectos ecomorfológicos e ultrassonograficos da reprodução em Sciades herzbergii (Teleostei: Ariidae)

2024-01-01T00:00:00Z

Título: Aspectos ecomorfológicos e ultrassonograficos da reprodução em Sciades herzbergii (Teleostei: Ariidae) Abstact: Estuarine areas, habitat of the Sciades herzbergii, have been increasingly suffering from anthropogenic actions, which in the long term could cause irreversible damage to the maintenance of this species and others that use this area to survive and maintain their natural stocks. In this way, we aim to learn about the reproductive maturational development of S. herzbergii through the ecomorphological, metabolic and ultrasound patterns. Specimens of S. herzbegii were collected in estuaries on Maranhão Island. After capture, the specimens were anesthetized in water containing 3% Benzocaine. Ultrasonography was performed in the region of the coelomic cavity, aiming to observe the gonads. The total length, standard length and total mass were obtained, followed by dissection and removal of the gonads, which will also be weighed and examined macroscopically. The gonads were collected for measurement, macroscopic and histological analysis. The developmental stages of the gonads of both sexes were verified macroscopically, based on the degree of turgidity, color, vascularization, visualization of gametes and weight/length of the gonads. Data analysis was carried out using the Statistical Analysis System for Windows SAS® software. The fish in this study showed negative allometry, investing more in increasing length than in weight as a growth strategy. The sex ratio was 4 females for each male (4:1). 5 maturation stages were found for S. herzbergii: immature, maturing, mature, regression and regeneration. Microscopically, within these stages, 7 phases of oocyte development were found: I, II, III, vtg1, vtg2, vtg3 and atresia. In this way, S. herzbergii presented asynchronous development, releasing oocytes as they mature. The species showed a predilection for spawning during the rainy season. This research brought unprecedented data and allowed the understanding of the different stages of the reproductive process of S. herzbergii, contributing to the knowledge of the reproductive dynamics of this species.

Esporotricose felina em São Luís-MA: análise retrospectiva, estimativa exploratória e desenvolvimento de ferramenta tecnológica para controle.

2026-02-12T00:00:00Z

Título: Esporotricose felina em São Luís-MA: análise retrospectiva, estimativa exploratória e desenvolvimento de ferramenta tecnológica para controle. Abstact: Sporotrichosis is a fungal zoonosis caused by species of the genus Sporothrix, whose relevance to public health has been increasing, particularly due to the high susceptibility of felines and their potential for transmission to humans. In this context, the present study aimed to evaluate the occurrence of feline sporotrichosis in São Luís, Maranhão, Brazil, from 2020 to 2024, seeking to identify temporal patterns and project future trends of the disease. A retrospective study was conducted based on the analysis of 695 positive cytopathological reports obtained from five veterinary laboratories. Variables related to animal profile, monthly distribution of cases, frequency among species, and geographic origin of the diagnosed animals were investigated. In addition, linear and polynomial regression models were applied to estimate temporal trends through 2025, along with a spatial analysis of cases within the municipality. The results showed a progressive increase in the number of diagnoses over the years, with a higher frequency in male cats (65.2%) compared to females (34.8%). Regarding age group, young adults predominated, accounting for 37.7% of the cases. Concerning breed, there was a marked predominance of mixed-breed animals (684 cases), while only 11 cases involved defined breeds. Monthly distribution indicated variation throughout the year, with fewer records in February and a higher concentration in October. Regression analyses, adopting a significance level of 5% (p < 0.05), indicated a continuous upward trend for 2025. Spatial analysis revealed a cluster with greater concentration in the Cidade Operária region, as well as the emergence of a new focus in the Itaqui-Bacanga area. Based on these findings, the educational application “EsporoVet” was developed to disseminate information on clinical signs, prevention, and appropriate disease management, contributing to health education initiatives and zoonosis control. The development process was structured into four main stages: selection of scientific content, prototype design, development using mobile technologies, and deployment for user access. Overall, the results highlight the expansion of feline sporotrichosis in the municipality and reinforce the need for integrated strategies involving veterinary services, public health, and the community.