Pedro Henrique Cotrin Rodrigues

Peri-urban forest fragments used for ecotourism concentrate interactions among wildlife, domestic animals, and humans, creating conditions that favour pathogen transmission through environmental, vector-borne, and trophic pathways. In these landscapes, synanthropic small mammals may act as integrative indicators of pathogen exposure since they interact with wildlife, domestic animals, and human-modified environments. This study conducted multi-pathogen surveillance in synanthropic small mammals to investigate infection patterns at a wildlife–urban interface in a Brazilian ecotourism area. Seventeen individuals belonging to three species (Nectomys squamipes, Didelphis albiventris, and Marmosops incanus) were sampled in a peri-urban forest fragment. Multiple tissues were screened by PCR assays targeting protozoan, helminth, and bacterial pathogens, and fecal samples were examined using parasitological techniques for intestinal parasites. Amplicons were sequenced and phylogenetic analyses were performed to support taxonomic assignment. A diverse assemblage of protozoa, bacteria, and helminths was detected, including Toxoplasma gondii, Hepatozoon sp., Babesia sp., Cryptosporidium sp., Cystoisospora/Isospora spp., and members of the family Anaplasmataceae (Anaplasma/Ehrlichia-like), as well as intestinal trematodes, cestodes, and nematodes (Strongyloides, Syphacia, Toxocara). Rickettsia spp., Bartonella spp., and hemotropic Mycoplasma were also detected. Coinfections were frequent, reflecting exposure to multiple ecological transmission pathways. These findings support the use of synanthropic small mammals as sentinels of pathogen circulation at wildlife–urban interfaces and highlight their relevance for integrated One Health surveillance in rapidly changing peri-urban landscapes.

Rangeliosis is a severe, emerging hemoparasitic disease affecting dogs in South America, caused by the protozoan Rangelia vitalii and transmitted by Amblyomma aureolatum, an ixodid tick found in the Atlantic Forest biome. Although cases are commonly reported in southern Brazil and in southeastern states such as São Paulo and Rio de Janeiro, reports from the state of Minas Gerais remain scarce. This study describes a natural infection by R. vitalii in a dog from the metropolitan region of Belo Horizonte, Minas Gerais, Brazil. Peripheral blood smears revealed intra- and extra-erythrocytic piroplasms. Molecular testing detected DNA from the order Piroplasmida (18S rRNA and hsp70 genes). Genetic sequencing of the amplified piroplasmid fragments revealed 99.83% similarity with R. vitalii. This is the first study to report the ante-mortem molecular diagnosis of R. vitalii in a dog, along with clinical treatment and recovery, in the state of Minas Gerais, Brazil.

Cyclopes, the smallest of all known anteaters, has an insectivorous diet and is arboreal, rarely descending to the ground. There are scarce reports on diseases and pathogenic agents affecting this taxon. Hemopathogens are pathogenic agents that inhabit the blood of various vertebrate species. Protozoa such as Trypanosoma spp., Leishmania spp., Hepatozoon spp., and members of the order Piroplasmida, as well as hemoplasmas and Rickettsial bacteria of the genera Anaplasma and Ehrlichia, are among the most important in this group. The transmission of these pathogens generally occurs through arthropod vectors, which act as intermediate hosts. In addition, infections caused by hemopathogens can have adverse effects on host health, contributing to population declines in susceptible species. This study investigated infection by protozoa and hemotropic bacteria in blood samples from free-ranging silky anteaters from Brazil, Peru, and Colombia using molecular detection methods. Sixteen samples were obtained during expeditions conducted in these countries. DNA was extracted from blood samples, and PCR assays were performed to detect parasites from the order Piroplasmida, Hepatozoon spp., trypanosomatid agents including Leishmania spp., Trypanosoma evansi, T. cruzi, and T. vivax, as well as hemotropic bacteria of the genera Ehrlichia, Anaplasma, and Mycoplasma sp. Nucleotide sequencing was performed on positive samples. Of the total samples analyzed, 62.5% (10/16) tested positive for hemotropic Mycoplasma, 50% (8/16) for T. evansi, and 6.2% (1/16) for T. cruzi. There is a significant gap in knowledge regarding the diversity of hemopathogens affecting the genus Cyclopes, and future studies are needed to understand how these infections may impact the health of individuals.

The captive native adult psittacines at human care, Amazona aestiva (blue-fronted parrot) and Ara chloropterus (red-and-green macaw), clinically affected with reduced activity/appetite and poor feathering, one found dead Anodorhynchus hyacinthinus (hyacinth macaw) and two exotic dead-in-nest Psittacula krameri (rose-ringed parakeet) were examined for signs and for ante- and post-mortem lesions, and for the presence of avian polyomavirus (APyV; Gammapolyomavirus avis) T/t genes. All individuals were tested-positive for APyV in skin and/or in other tissues such as blood, brain, liver, skin and spleen, and all were tested-negative for psittacine circovirus (BFDV). However, no association was found between the detection of APyV and the presence of macro or microscopic lesions. The APyV sequences detected in the A. aestiva and P. krameri were grouped together with high identity, which may suggest common origins. However, the sequence detected in A. hyacinthinus was dissimilar and grouped separate. The sequences detected had high identity with T/t gene sequences of strains previously described in distinct continents. The evaluation of avian species for APyV may not be available nor demanded in the international avian trade and may represent an avian health hazard. The biosecurity of the commercial avian pet flocks and the captive avifauna in rehabilitation is considered essential.

In captive environments, mammals are frequently exposed to various parasitic protozoa and other vector-borne pathogens that can impact both animal health and public health. Monitoring these pathogens is essential for animal welfare and zoonotic disease control. This study aimed to investigate the prevalence of parasitic protozoa and other vector-borne pathogens in captive mammals through molecular detection methods at the Belo Horizonte Zoo, Brazil. Between November 2021 and March 2023, whole blood samples were collected from 40 mammals. Molecular analyses identified piroplasms, Leishmania spp., granulocytic/platelet Anaplasma/Ehrlichia spp., monocytic Ehrlichia spp., Bartonella spp. and hemotropic Mycoplasma spp. with a 72.5% positivity rate. Piroplasms were found in 22.5% (two Pantanal cats, two gorillas, one white rhinoceros, one spider monkey, one jaguar, one tufted capuchin and one hippo) and Leishmania spp. in 12.9% (four maned wolves). Granulocytic/platelet Anaplasma/Ehrlichia spp. were found in 12.5% of the samples (one gorilla and four maned wolves), Ehrlichia canis in 2.5% of the animals (one maned wolf), Bartonella spp. in 42.5% (six howler monkeys, two maned wolves, one gorilla, one white rhino, one southern tamandua, one common woolly monkey, one tufted capuchin, one brown brocket deer, one agouti, one cougar and one hippo), hemotropic Mycoplasma spp. in 17.5% (one gorilla, one maned wolf, one white rhino, one howler monkey, two common woolly monkeys and one European fallow deer). Five Artiodactyla members tested negative for A. marginale. Coinfections occurred in 34.5% of the positive samples. Sequencing revealed that Theileria spp. and Cytauxzoon spp. are closely related to Theileria bicornis and Cytauxzoon felis; Ehrlichia canis and Bartonella spp. are closely related to B. clarridgeiae and B. henselae; and hemotropic Mycoplasma spp. are closely related to Candidatus Mycoplasma haemominutum. Our results showed a high occurrence of vector-borne pathogens in captive animals, including zoonotic species, which may pose a risk to animal and human public health.

Avian species of the metropolitan region of Belo Horizonte, Brazil, submitted to laboratory routine due to a variety of morbid conditions, were diagnosed as carriers of Blastocystis sp. All samples were examined under light microscopy and those with structures suggestive of Blastocystis sp. were tested by PCR. The total DNA was purified from feces and/or intestinal mucosa and used as a template for PCR, targeting the small subunit (SSU) rRNA gene, and the products were sequenced. The sequences detected in two chickens, one passerine (Saltator similis, Thraupidae) and a golden parakeet (Guaruba guarouba, Psittacidae) were phylogenetically characterized and shown to cluster with sequences of subtypes 2, 4 or 9. The occurrence of Blastocystis sp. in domestic and local native avifauna is described and the perspective of a complex local interspecies epidemiology is considered of risk, including to humans.