Hudson Alves Pinto

The present study aimed to investigate the anatomopathological findings in ornamental fish from multiple sources, submitted to the diagnostic service at the Veterinary School of the Universidade Federal de Minas Gerais (UFMG) between 2019 and 2023. Macroscopic and histopathologic examinations were conducted, and the resulting data regarding disease processes were analyzed through a descriptive observational approach. A total of 635 ornamental fish were studied, with a predominance of exotic fish species. The fish were sourced from ornamental fish farms (37.00%; 235/635), shopkeepers (32.44%; 206/635), facilities (18.43%; 117/635), hobbyists (8.66%; 55/635), and wholesalers (3.46%; 22/635). Among the analyzed cases, 50.39% (320/635) presented relevant anatomopathological findings. The main categories of diseases detected were parasitic (56.25%; 180/320), bacterial (20.31%; 65/320), fungal/oomycete (7.50%; 24/320), viral (7.18%; 23/320), neoplastic (1.88%; 6/320), congenital (2.50%; 8/320), and metabolic (0.94%; 3/320). The main parasites found were unidentified digeneans (15.45%; 34/220), presumed Centrocestus formosanus (14.55%; 32/220), monogeneans (13.18%; 29/220), presumed Tetrahymena spp. (8.18%; 18/220), and presumed Epistylis (6.36%; 14/220). There were diagnoses of undocumented diseases in Brazil, such as the suggestive cases of Ichthyophonus spp. In addition, novel potential pathogen–host associations in the country were documented, such as Pleistophora sp. in Carnegiella strigata. This study presents findings that can contribute to determining disease frequency and identifying pathogens based on microscopic lesions.

This study reports trematode infection in tadpoles at early developmental stages under natural conditions. While most previous records describe infections in more advanced stages, we identified metacercariae of the diplostomid Neodiplostomum sp. in tadpoles of five anuran species at the Gosner stage between 25 and 28. A total of 207 tadpoles from eight species (Families Hylidae and Leptodactylidae) were collected from seasonal water bodies from Brazil, of which 39 were found parasitized with helminths. Within this group of infected tadpoles, 20 were specifically parasitized by trematodes, 12 of them at the earliest stages of tadpole development (Gosner stage 25). This record indicates that tadpole infection with trematodes may occur earlier than previously documented, providing new insights into the infection dynamics of larval trematodes.

Anurans are bioindicators and key components of ecosystem functions. Although South America harbors more than 4,000 identified anuran species, fewer than 10% have been analyzed regarding their trematode fauna. When tadpoles are considered, the paucity of studies becomes even more evident. Considering the ability of digeneans to serve as indicators of ecosystem health, it is evident that there is a gap in the knowledge of trematodes occurring in anuran biodiversity hotspots. Herein, we provide an ecological and morphological analysis of the trematode component community recovered in tadpoles and adult anurans. During a long-term herpetological and helminthological study conducted in a Cerrado fragment in Brazil, 569 anurans from 17 species were necropsied. Eleven species were common to both adults and tadpoles, and six species occurred only in adults. The total prevalence was 61% (352/569), in separate analyses, 65% (192/296) for adult anurans, and 58% (160/273) for tadpoles. A total of 12,397 trematodes belonging to 16 taxa were recovered. The component community was composed mostly of metacercariae. We provided a brief morphological description for each trematode taxa recovered. Additionally, statistical analysis was performed to elucidate the differences between tadpoles and adult anurans trematode communities. The trematode community analyzed in our study revealed 24 new host records and was the first to include tadpoles in such an analysis, highlighting the importance of faunistic inventories for a better understanding of parasitism in their hosts, as well as providing a foundation for further research.

This study aimed to identify larval forms of trematodes in Pseudosuccinea columella from rural properties with a history of bovine fasciolosis in the southern region of Espírito Santo, Brazil. A malacological survey was carried out on waterbodies from ten properties between June 2022 and March 2023. Aquatic snails were collected, identified, and evaluated for infection with trematode larvae by artificial photostimulation. The larvae found were morphologically characterized under a light microscope, and samples of the snails were subjected to histological analysis to observe larval trematodes in development in snails' tissues. A total of 678 specimens of P. columella were collected in nine properties, and larval trematodes were identified in 24 (4.08%) specimens from seven properties. A xiphidiocercaria morphotype, compatible with Haematoloechidae, was found in six properties. A morphotype of echinostome cercaria, compatible with the Echinostoma genus, was found in one property (2.17%). Larval Fasciola hepatica was not observed. Ecological studies are needed to investigate the environmental factors that may be related to the absence of natural infection of snails by F. hepatica, especially considering the presence of positive cattle in the evaluated properties. The data presented here reveal that P. columella a potencial vector role in the studied area.

We examined the recent surge in misinformation surrounding giant hammerhead flatworms (Bipaliinae, primarily Bipalium kewense), which has generated widespread confusion across multiple countries regarding their risks to human health. Prompted by a routine taxonomic identification, this study aims to restore scientific accuracy and address the growing disconnect between science and the public concerning these worms, which have become an Internet sensation. In late 2023, we were asked to identify specimens collected in Pedro Leopoldo, Minas Gerais, Brazil, that had already attracted considerable online and regional media attention, warning of a “new, invasive, and dangerous worm” and its supposed threats. After confirming the species was B. kewense, we reviewed the literature, constructed a timeline of scientific and media reports, and compared information retrieved from Google News and Google Scholar. Our findings indicate that while academic research on invasive species has steadily increased, sensationalized and often inaccurate content on hammerhead worms proliferated in the general media, particularly between 2017 and 2018. Notably, claims (2023-2024) regarding the toxicity of Bipalium spp. lack scientific support. This case illustrates the broader challenges of health misinformation in the digital age, where misleading narratives rapidly transcend countries and languages. We discuss potential drivers, including communication gaps between academia and the public, the influence of media and social networks, and behavioral factors underlying misinformation. Finally, we highlight the urgent need for innovative strategies and coordinated efforts to strengthen online science communication and ensure the dissemination of accurate information.

Trematodes of the family Cyclocoelidae are parasites mainly of the respiratory system of birds and present a cosmopolitan distribution. Although infection with these flukes can result in pathological changes and even bird death, information on their life cycles is scarce and almost entirely based on experimental infection data. Thus, the generation of knowledge on the mollusks that act as natural intermediate hosts of cyclocoelids is necessary and can aid control measures against these air sac trematodes. In the present study, gastropod mollusks collected in an urban stream from Belo Horizonte, Minas Gerais, Brazil, were subjected to the compression technique for the detection of non-emerging larval trematodes. Tailless cercariae with confluent ceca were found in 8/30 (26.7%) specimens of Biomphalaria glabrata and 3/33 (9.1%) specimen of Physella acuta. Samples of the cercariae were subjected to morphological characterization and genetic study (28S, Cox-1, and Nad-1). For comparative purposes, adult trematodes previously collected in the air sac of a common gallinule (Gallinula galeata) found dead in another waterbody from the same region were also characterized. The molecular sequences obtained revealed a high degree of similarity (100% in 28S, 99.2% in Cox-1, and 99.5% in Nad-1) between larval stages found in mollusks and adult parasites found in G. galeata and morphologically identified as Cyclocoelum mutabile. The conspecificity with this widely distributed cyclocoelid was also corroborated by phylogenetic analysis and comparison with isolates of this species previously characterized in Peru and the Czech Republic (99.4–100% and 96.7–97.0% of similarity in Nad-1, respectively). Thus, the integrative analysis carried out in the present work enabled us to identify C. mutabile in mollusks in South America for the first time. The finding of B. glabrata and P. acuta as new intermediate hosts corroborates the importance of freshwater gastropods in the transmission of C. mutabile, as well as the low specificity to the mollusk group, as previously characterized through experimental studies.

This study presents the first record of T. lindbergi from the southwestern Atlantic Ocean, based on specimens collected from the smalleye croaker Nebris microps Cuvier (Sciaenidae), off the coast of Maranhão Island, State of Maranhão, Brazil. Our approach included a morphological analysis complemented by DNA sequencing (28S, ITS2 rDNA, and cox1 mtDNA). Our phylogenetic analysis revealed the affinity of T. lindbergi to its congener T. laticaudi Parukhin, 1969, a digenean parasite commonly found in hydrophiine snakes inhabiting the Pacific Ocean. The interspecific divergence between T. lindbergi and T. laticaudi measures 3.80% for 28S, 7.49–7.64% for ITS2, and 16.29–16.70% for cox1. Our findings expand the documented geographic range of T. lindbergi into the southwestern Atlantic Ocean, report a novel host record, and increase the number of hemiurids known from Brazil to 30 species. Additionally, this study represents the initial documentation of a marine digenean fish within the North Brazil Shelf.