Anna Claudia Baumel Mongruel

Hemotropic mycoplasmas (hemoplasmas) are epicellular bacteria of the Mycoplasma genus capable of attaching to mammalian erythrocytes. Recently, reports of hemoplasmas in Brazilian wildlife have increased exponentially, reflecting advances in molecular diagnosis, bioinformatic analyses, and broader access to these tools. The present scoping review updates the current available information on hemoplasmas occurrence and genetic diversity in Brazilian wildlife, including terrestrial, aquatic, and flying mammals, as well as exotic species. The review included 59 scientific papers published between 2007 and 2025. Most records are concentrated in the Atlantic Forest and Pantanal biomes, with rodents showing the highest genetic diversity, potentially reflected by a larger number of analyzed samples. Some mammal groups harbor apparently host-specific hemoplasmas lineages, such as tapirs (Tapirus terrestris), opossums (Didelphis spp.), crab-eating raccoons (Procyon cancrivorus), and neotropical otters (Lontra longicaudis). Collectively, available data demonstrate that hemoplasmas are widespread and frequently reported in Brazilian wildlife. Although the use of multi-locus sequencing and comprehensive phylogenetic reconstructions have provided additional insights when compared to single-gene analyses, their resolution is still limited for clarifying the evolutionary relationships and taxonomic placement of hemoplasmas. Looking ahead, advances in genomic comparisons may further deepen our understanding of hemoplasmas diversity and evolution.

Canine otitis externa (OE) presents a significant challenge in veterinary medicine due to its complex, multifactorial nature and the growing issue of antimicrobial resistance (AMR) associated with conventional antibiotic use. The objective of this study was to compare the efficacy of a novel, antibiotic-free topical ear solution (Therapy A) containing antimicrobial peptides and encapsulated plant extracts (chamomile, calendula, rosemary, and hops) against a standard conventional treatment (Therapy B) composed of gentamicin, betamethasone valerate, and clotrimazole. A longitudinal, randomized study was conducted over four weeks with 40 domestic dogs diagnosed with OE. The dogs were divided into two groups, each receiving one of the therapies. Evaluations were performed weekly, assessing clinical signs using the Otitis Index Scoring System (OTIS-3) and a pruritus visual analog scale (pVAS), as well as ear canal pH and cytology. The results showed that Therapy A provided similar clinical efficacy in OTIS-3 and pVAS scores that were comparable to Therapy B. Cytological analysis also revealed a significant reduction in microbial presence for both groups. Notably, Therapy A was clinically effective in two of the three dogs presenting multi-drug resistant (MDR) bacterial infections. The novel formulation also demonstrated a favorable safety profile, with no adverse drug reactions reported, in contrast to one dog in the conventional treatment group that experienced an adverse reaction. These findings suggest that the plant-based formulation is a safe and effective alternative for managing canine OE, offering a promising solution to reduce the reliance on antibiotics and corticosteroids.

Piroplasmids (Babesia spp., Rangelia spp., Theileria spp., Cytauxzoon spp.) are tick-borne apicomplexan protozoa that infect, depending on the species, erythrocytes and leucocytes in a wide variety of mammals and birds. The genera Bartonella and Borrelia include vector-borne bacteria that can infect and cause disease in both animals and humans. Detection of hemotropic bacteria and piroplasmids in wild animals is often challenging due to low bacteremia or parasitemia. Digital (d)PCR has proven to be an effective modality for the detection and quantification of DNA of hemotropic pathogens with low parasitemia. This study compared dPCR results from 366 biological samples from seven different Brazilian wild animal groups (5 Xenarthra species, 5 deer species, 3 felid species, 1 canid species, 3 rodent species, 1 bat species, 1 tapir species, and 12 bird species) to two other molecular diagnostic techniques: quantitative real-time (qPCR) and nested (nPCR). For this study, DNA extracted from wild animal blood and spleen samples were subjected to a multiplex dPCR assay for piroplasmids, Bartonella spp., and Borrelia spp. For comparison, the same primers and probes for each agent were used in qPCR assays. Additionally, an nPCR based on the 18S rRNA gene for piroplasmids was performed. The proportions of positive results obtained using dPCR were 85.5% for piroplasmids, 33.6% for Bartonella spp., and 16.7% for Borrelia spp. For all tested agents, dPCR proved to be the technique with the highest sensitivity, making it a useful tool for screening vector-borne agents in biological samples from wild animals with low parasitemia.

Representatives of the families Didelphidae, Echimyidae, Cricetidae, and Muridae have been identified as significant reservoirs or amplifiers of zoonotic agents. This study aimed to investigate the molecular occurrence of Bartonella spp., Ehrlichia spp., Anaplasma spp., and hemotropic Mycoplasma spp. (hemoplasmas) in small synanthropic mammals in different urban complexes in Brazil’s northern Amazon region. Between January and August 2022, blood samples were collected from 36 small mammal specimens, belonging to ten different species living in three vegetation fragments located in the metropolitan areas of Macapá, in the state of Amapá, and in Santarém and Marabá, state of Pará, Brazil. After DNA extraction, samples were subjected to real-time quantitative PCR (qPCR) for Bartonella spp. based on the nuoG gene, and to conventional PCR assays for Ehrlichia spp., Anaplasma spp., and hemoplasmas based on the dsb and 16S rRNA genes, respectively. This is the first record of Anaplasma spp. and hemotropic Mycoplasma sp. in marsupials in northern Brazil. Bartonella spp. was detected only in small mammals from Macapá, expanding the list of known hosts. This study describes findings on potentially zoonotic pathogens associated with small mammals living in green areas of large urban complexes in the Brazilian Amazon.