Search Results (222)

Candida spp. are ubiquitous yeasts that are part of most mammals’ microbiota and can become opportunistic pathogens under predisposing conditions. Interestingly, recent studies in human medicine report an increased abundance of Candida spp. in association with inflammatory bowel disease (IBD). Gastrointestinal candidiasis has been primarily reported in neonatal foals, but not in adult horses. The aim of this study is to describe the morphological, histopathological, and microbiological features of gastric lesions associated with Candida infiltration in five horses referred to two tertiary hospitals for different reasons. Clinical features, findings from gastroscopy, gastric, and duodenal biopsies, as well as fungal and bacterial cultures obtained from gastric lesions will be reported. Macroscopically, gastric lesions showed a characteristic yellow/white pseudo-membranous appearance, similar to lesions reported in foals. The presence of Candida spp. was confirmed by positive culture and/or histopathological evidence of fungal infiltration on the gastric epithelium. Three out of five horses showed histopathological changes in duodenal biopsies, potentially suggesting IBD. These results demonstrate that gastric candidiasis can occur in adult horses. Further research is needed to elucidate the pathogenesis, predisposing factors, and clinical relevance of Candida spp. infections in the equine stomach, as well as their potential impact on gastrointestinal health and overall performance. Full article

Aeromonas salmonicida is an age-old fish pathogen widely distributed in seawater and freshwater environments that causes significant economic losses to the global aquaculture industry. Genetic mutations and the emergence of thermophilic strains are factors in the continuous expansion of A. salmonicida’s host range. Beyond infecting fish, A. salmonicida poses a potential threat to mammalian and human health. This review synthesizes recent global research advances concerning A. salmonicida, encompassing strain characteristics, genomic features, virulence factors, and pathogenic mechanisms, as well as the clinical manifestations in infected fish and mammals, and discusses prevention and treatment methods. Particular emphasis is placed on evaluating the potential prophylactic roles of Chinese herbs and bacteriophages against A. salmonicida infection. Furthermore, the review provides perspectives on future research directions, diagnostics, and disease management, informed by contemporary domestic and international studies on this pathogen. Full article

Most infectious diseases affecting humans are zoonotic in origin, with mammals serving as the main reservoirs. Frequent interactions between humans and animals, especially in the context of their use for food, medicine, and other purposes, pose significant public health risks, as recently demonstrated by the SARS-CoV-2 pandemic. In traditional medicine, many species—some of which are also used as food—are valued for their therapeutic versatility, that is, the diversity of medicinal uses attributed to each species. This study investigates the role of zoonotic potential in the selection of mammals used in traditional medicine at a global scale. We compiled data on 411 wild mammal species across 17 orders, identifying 5.146 associated pathogens, of which 2.778 (53.9%) also infect humans. Most diseases transmitted by these species are caused by viruses (33.4%), bacteria (23.3%), and helminths (22.3%). These mammals are used to treat at least 500 diseases or symptoms, and 4.3% of the species show high therapeutic versatility (RI > 1). Our results indicate that species selection is shaped by both biological and cultural factors, with zoonotic potential being the most influential: species with a higher risk of disease transmission tend to be less used. These findings highlight the importance of incorporating zoonotic risk into research and policies regarding the medicinal use of wildlife. Full article

Aspergillus spp., particularly A. fumigatus, are increasingly reported as emerging pathogens in cetaceans, yet their clinical and ecological relevance remains poorly characterized. This systematic review synthesizes evidence from 34 studies involving 106 animals, identifying respiratory, neurological, and otic infections as the most frequent presentations with potential interspecies tropism. Invasive disease, frequently fatal, was linked to co-infections—especially with morbillivirus—and environmental stressors such as pollution- and climate-related immune suppression. Despite cetaceans’ role as sentinel species, antifungal susceptibility testing and species-level identification were inconsistently performed. Additionally, azole-resistant A. fumigatus strains were isolated from wild porpoises, indicating environmental antifungal exposure and potential public health implications. Aspergillosis remains underdiagnosed in free-ranging populations, particularly in remote or pelagic species. Conservation implications were scarcely addressed, despite evidence suggesting that fungal disease may contribute to morbidity, stranding, and population impact. This review underscores the need for enhanced surveillance, integrative diagnostics, and recognition of fungal pathogens in a One Health framework. The growing intersection of climate change, emerging mycoses, and wildlife conservation positions Aspergillus infections in cetaceans as both a marine mammal health concern and an ecological indicator of broader environmental changes. Full article

Rodents represent the most diverse order of mammals, comprising over 2200 species and nearly 42% of global mammalian biodiversity. They are major reservoirs of zoonotic pathogens, including viruses, bacteria, protozoa, and fungi, and are particularly effective at transmitting diseases, especially synanthropic species that live in close proximity to humans. As of April 2025, approximately 15,205 rodent-associated viruses have been identified across 32 viral families. Among these, key zoonotic agents belong to the Arenaviridae, Hantaviridae, Picornaviridae, Coronaviridae, and Poxviridae families. Due to their adaptability to both urban and rural environments, rodents serve as efficient vectors across diverse ecological landscapes. Environmental and anthropogenic factors, such as climate change, urbanization, deforestation, and emerging pathogens, are increasingly linked to rising outbreaks of rodent-borne diseases. This review synthesizes current knowledge on rodent-borne viral zoonoses, focusing on their taxonomy, biology, host associations, transmission dynamics, clinical impact, and public health significance. It underscores the critical need for early detection, effective surveillance, and integrated control strategies. A multidisciplinary approach, including enhanced vector control, improved environmental sanitation, and targeted public education, is essential for mitigating the growing threat of rodent-borne zoonoses to global health. Full article

Autochthonous Chagas disease remains a health risk for humans in Latin American countries but is rarely found among residents of the United States (US), despite the presence of competent insect vectors and small mammal reservoirs of Trypanosoma cruzi in the lower two-thirds of the US. This report discusses the differences in the rates of autochthonous Chagas disease in Latin America and the US. The key to the differences may lie in the mode (or means) of transmission of parasites to humans. In both Latin America and the US, the so-called vectorial transmission of Chagas disease to humans is the mode of acquisition accepted by most authorities. This mode involves the improbable combination of an infected kissing bug defecating near the mouth or eyes or the site of the bite, followed by the bite victim rubbing infected feces into the wound site or mucous membranes. Outbreaks of Chagas disease due to fecal–oral contamination, known as oral Chagas, have been recorded in Latin America for decades, and at present, oral Chagas is the predominant mode of infection recognized in Brazil. It is perhaps time to consider fecal–oral transmission in its many manifestations as a risk factor for Chagas disease in the US rather than reflexively invoking vectorial transmission. Fecal–oral transmission includes contamination of food and drink by triatomine feces and infection via contaminated fomites and surfaces at home and at worksites, as well as transmission from infected small mammals and other routes discussed in this report. Full article

Mycobacterium is one of the most dangerous pathogens of both animals and humans. Bovine tuberculosis (BTB) is a disease caused by mycobacteria belonging to the Mycobacterium tuberculosis complex (MTBC), which spreads mainly among domestic cattle but also to mammals other than cattle. The transmission of MTBC between different species requires research and epidemiological investigations to control its spread. When multiple species are a reservoir of infection, it poses a significant public health and veterinary concern. In this study, the diagnosis of alpaca, cattle, horses, dogs, a sheep and a cat from one farm suspected of bovine tuberculosis was performed. The animals (except for one horse, the dogs and the cat) were euthanised after the intradermal tuberculin tests. Mycobacterial isolation from animal tissue samples was performed. The obtained Mycobacterium strains were genotyped using spoligotyping and mycobacterial interspersed repetitive unit–variable number tandem repeat (MIRU-VNTR) methods. The isolates from a horse, two cows, a sheep and an alpaca were classified as Mycobacterium (M.) bovis. The single M. bovis spoligotype SB0666 pattern was isolated, and the MIRU-VNTR results presented the same 222632237401435 patterns. The molecular investigation uncovered information on the relationship of Mycobacterium bovis. Full article

In recent years, zoonotic pathogens have become increasingly more relevant in scientific research due to their implications on public health. Understanding their pathogenic potential, the pathways they use to infect and their reservoirs enables better care for both human and animal patients, and possible infection outbreaks can be more easily contained. Bartonella belongs to a vast list of zoonotic pathogens that can infect mammals, including humans, but also companion animals and wildlife, and is capable of causing disease. Bats are a possible source and reservoir of this bacterial genus, and Bartonella spp. has already been identified in these animals in several countries. Using these premises, skin samples of the pinna and wing of 71 bats (Pipistrellus pipistrellus) collected from southern Portugal were tested through PCR for the presence of Bartonella spp., and positive results were found in 1.41% (1/71). The sequence obtained shared genetic proximity with an already known pathogenic Bartonella strain that affects both humans and animals. From the public health perspective, these findings suggest that bats may play a role in the transmission of this pathogen and provides new insights into the presence of this agent in Portugal. Full article

Avian influenza (AI), caused by Alphainfluenzavirus (family Orthomyxoviridae), poses significant threats to poultry, biodiversity, and public health. AI outbreaks in poultry lead to severe economic losses, while highly pathogenic strains (HPAIVs) severely impact wild bird populations, with implications for biodiversity and potential zoonotic risks. Similarly, arboviruses such as West Nile virus (WNV) and Usutu virus (USUV) are emerging zoonoses. WNV can cause severe neurological diseases in birds, humans, and other animals, while USUV significantly affects blackbird populations and has zoonotic potential, though human cases remain rare. This study investigated avian viruses in 1654 wild birds from 75 species that died at the Wildlife Rescue Center in Vanzago, Lombardy, during 2023–2024. Necropsies were conducted, and virological analyses were performed to detect avian influenza viruses, WNV, and USUV. Among the tested birds, 15 were positive for H5N1 HPAIV clade 2.3.4.4b, all in 2023, including 13 Chroicocephalus ridibundus, one Coturnix coturnix, and one Columba palumbus. Additionally, 16 tested positive for WNV (15 for lineage 2 and one for lineage 1), one for USUV, and 11 co-infections WNV/USUV were recorded in 2023–2024. These findings underscore the importance of avian viral passive surveillance in identifying epidemiological trends and preventing transmission to other species, including mammals and humans. Full article

West Nile virus (WNV) is an important zoonotic pathogen belonging to the Flaviviridae family, which is endemic in some areas and emerging in others. WNV is transmitted by blood-sucking mosquitoes of the genus Culicoides, Aedes, and Anopheles, and the infection can cause different clinical symptoms. The most common and benign illness in humans is West Nile fever (WNF), but a lethal neurological disease (WNND), related to the neuro-invasiveness of WNV lineage 2, represents the highest health risk of WNV infection. The neuro-clinical form is recognized in mammals (land and cetaceans), particularly in humans (elderly or immunosuppressed) and in horses, avian species, and wildlife animals ranging free or in a zoological setting. This review highlights the most relevant data regarding epidemiology, virology, pathogenesis and immunity, clinical signs and differential diagnosis, pathology and imaging, histopathology and gross pathology, economic impact, influence of climate change, and surveillance of WNV. Climate change has favored the wide spread of WNV in many areas of the globe and consequent One-Health and Eco-Health emergencies, influencing the health of human beings, animals, and ecosystems. Full article

Adult mesenchymal stem cells (MSCs) play a crucial role in maintaining bone health and promoting regeneration. In our previous research, we identified Gli1⁺ MSCs as key contributors to the formation of most trabecular bone in adulthood and as essential for healing bicortical fractures. However, the mechanisms behind the maintenance and differentiation of Gli1⁺ MSCs are still not fully understood. O-linked N-acetylglucosamine modification (O-GlcNAcylation), mediated by O-GlcNAc glycosyltransferase (OGT), is involved in various biological processes and diseases. Our earlier work also demonstrated that O-GlcNAcylation is necessary for Wnt-stimulated bone formation. Nonetheless, the specific functions of O-GlcNAcylation in MSCs have not been completely elucidated. In this study, we found that the absence of OGT in Gli1⁺ MSCs led to a decrease in O-GlcNAcylation, which impaired both the bone formation and regeneration following fractures. Mechanistically, the Hedgehog signaling pathway induced O-GlcNAcylation through the insulin-like growth factor (Igf)-mTORC2 axis. This process stabilized the Gli2 protein at a specific site Ser355 and promoted osteogenesis in MSCs in vitro. Our findings reveal a significant mechanism by which O-GlcNAcylation regulates bone development and repair in mammals. Full article

Mastitis, a prevalent inflammatory disease in mammals, disrupts mammary gland function, compromises milk quality, and can contribute to increased offspring morbidity and mortality. Maintaining the health of porcine mammary epithelial cells (PMECs), the primary cell type in the mammary gland, is crucial for minimizing the adverse effects of this disease. Selenium yeast (SeY), an organic selenium compound known for its antioxidant and immune-enhancing properties, has yet to be fully understood in its role in modulating inflammation in mammary gland. In this study, lipopolysaccharide (LPS) (50 µg/mL, 24 h) significantly upregulated the expression of pro-inflammatory cytokines, including tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), interleukin-8 (IL-8), and interleukin-1β (IL-1β) (p < 0.05). Pretreatment with 1 µM SeY significantly attenuated the LPS-induced inflammatory response by reducing the levels of TNF-α, IL-6, IL-8, and IL-1β (p < 0.05). Additionally, SeY enhanced cellular antioxidant defenses by increasing total antioxidant capacity (T-AOC), superoxide dismutase (SOD) activity, glutathione (GSH) levels, and glutathione peroxidase (GSH-Px) activity, while concurrently decreasing malondialdehyde (MDA) accumulation (p < 0.05). SeY also restored both intracellular and extracellular triglyceride levels and rescued lipid droplet formation, which were disrupted by LPS treatment. Furthermore, SeY upregulated key regulators involved in milk synthesis (p < 0.05). These findings suggest that SeY effectively mitigates LPS-induced inflammation and oxidative stress while preserving critical pathways for milk fat and protein synthesis in PMECs. Full article

California sea lions (Zalophus californianus) are susceptible to various ocular diseases, with some literature suggesting a heightened risk for those kept in freshwater pools as opposed to saltwater. Given the potential implications of housing conditions on animal health, we wanted to analyze the ocular health of two distinct groups of California sea lions kept at Nuremberg Zoo, one housed in freshwater and the other in saltwater. Data extracted from the animals’ medical records during a ten-year period were used to compare the incidence of eye conditions and other medical conditions observed. The results revealed no significant difference in the overall occurrence of eye diseases between the two environments. However, a distinct seasonal pattern was noted: California sea lions kept in freshwater exhibited a peak in eye disorders during the summer months, while those in saltwater displayed a more uniform distribution of the occurrence of ocular diseases throughout the year. These findings suggest that sun exposure and water quality are potentially more influential factors in the development of ocular diseases in pinnipeds than salinity. Further studies are necessary to elucidate the underlying mechanisms and optimize care practices for these marine mammals. Full article

Leptospirosis is a zoonotic disease of global public health importance caused by bacteria of the genus Leptospira. Small non-flying mammals are important reservoirs of the pathogen. The Brazilian Atlantic Forest is a biodiversity hotspot located in a densely populated area and subject to intense degradation. Although documented through serosurveys and the detection of leptospiral DNA in wild small mammals, no study has performed a genetic characterization of the bacteria in the region. The present study aimed to evaluate the genetic diversity of pathogenic leptospires identified in small non-flying mammals in the Southeast Atlantic Forest and to perform intraspecific genetic inferences with other hosts. The studied area included five different conservation units. Molecular diagnosis was performed based on the lipl32 gene. The SLST typing method was applied based on the secY gene. In total, 56% of samples were lipL32-PCR-positive and identified as L. interrogans, with a high genetic identity among them, distributed in four main haplogroups. The largest haplogroup also included reference sequences from humans, dogs, and urban rats, all belonging to the Icterohaemorrhagiae serogroup. Our results reinforce the role of small mammals as important carriers of L. interrogans and highlight the Atlantic Forest as a significant environment for the circulation and dissemination of spirochetes with zoonotic potential. Full article

Infections with the zoonotic pathogen Yersinia (Y.) pseudotuberculosis are commonly causing clinical diseases and acute deaths in various mammal and bird species in zoos. These findings prompted us to conduct a targeted study that included animals of 18 German and 1 Swiss zoo that had been affected by the pathogen previously. This study provides a comprehensive overview of susceptible zoo animal species, clinical signs, therapies, antimicrobial resistance, pathogen monitoring, and prophylactic measures. In addition, fecal samples from species with documented infections and organ samples from deceased mammals and birds from two of the participating zoos, the urban zoo Wilhelma and the rural Opel Zoo, were examined for Y. pseudotuberculosis using both direct plating and enrichment. The overall prevalence of Y. pseudotuberculosis was 3.1% at the Opel Zoo and 1.3% at the Wilhelma. Fecal samples yielded positive results in 1.4% of the tested samples from the Opel Zoo but none from the Wilhelma. Among carcasses, 16.7% and 1.7% tested positive at the Opel Zoo and the Wilhelma, respectively (p = 0.006). Y. pseudotuberculosis was significantly more frequently isolated during the cold season (p = 0.002). Affected animals often died suddenly, displaying no or only non-specific clinical signs, but postmortem examinations revealed septicemia with multiple bacterial organ abscesses. Rodents, ruminants, primates, and Piciformes were the most commonly affected orders. Considering the zoonotic potential of Y. pseudotuberculosis, this research underscores the importance of investigations in zoos in accordance with the targets of the One Health approach. Full article