Search Results (302)

Bacillus anthracis is endemic in the United States causing periodic outbreaks in wildlife and domestic animals. Currently, human anthrax cases in the U.S. are rare but were common in the 1950s–1960s due to industrial work with imported B. anthracis-contaminated animal products. Multiple-locus variable-number tandem repeat analysis (MLVA) initially differentiated B. anthracis into 89 genotypes and two major clades. Recently, whole-genome sequencing (WGS) was implemented to differentiate B. anthracis which allows for higher resolution and can eliminate risk of homoplasy. To assess the molecular diversity of U.S.-established isolates, we performed MLVA and WGS on 81 B. anthracis isolates from domestic animals or soil. By MLVA, most isolates (n = 58, 72%) were in the Western North America (WNA)/A1.a cluster. Isolates were also observed in the Ames (A3.b), Vollum (A4), and Group B clusters. Using WGS, two major clades (A and B) and four clusters (WNA, Ames, Vollum, Group B) were identified. The four WGS clusters correlated with previously established MLVA clusters (A1a, A3b, A4, and B1, respectively). Further differentiation of the WNA cluster showed that isolates collected from the same state generally clustered together and more broadly by region (west, central, Texas). In the current study, we provide an update on the genetic diversity of domestically established B. anthracis strains using MLVA and WGS. WGS was able to provide additional differentiation, particularly within the WNA cluster, which can lend assistance in epidemiological investigations. Full article

In this study, we conducted a molecular investigation of hemotropic Mycoplasma spp. in bat species captured in the northern region of the Pantanal biome, Mato Grosso State, Brazil. Tissue samples were screened by qPCR targeting the 16S rRNA gene. Positive samples were subsequently subjected to conventional PCR assays targeting partial fragments of the 16S rRNA (~900 bp) and 23S rRNA (~800 bp) genes. Hemoplasma DNA was detected in four bat species: Glossophaga soricina, Molossops temminckii, Molossus rufus, and Desmodus rotundus. Phylogenetic analyses based on partial 16S and 23S rRNA gene sequences demonstrated that the detected hemoplasmas clustered predominantly with previously described bat-associated hemoplasmas from Brazil and other countries in the Americas. Notably, the detection in M. temminckii represents, to our knowledge, the first molecular evidence of hemotropic Mycoplasma infection in this bat species. These findings expand current knowledge regarding the occurrence, host range, and genetic diversity of hemotropic Mycoplasma spp. in bats from the Pantanal biome and contribute to wildlife surveillance efforts in this ecologically important region. Full article

Antimicrobial resistance is a major global health challenge that requires a One Health approach integrating humans, animals, wildlife, food systems and the environment. Among resistant bacteria, extended-spectrum β-lactamase-producing Escherichia coli (ESBL-producing E. coli) is particularly relevant because it is widely distributed across hosts and ecosystems, may carry mobile resistance genes and is commonly used as an indicator for antimicrobial resistance surveillance. This narrative review examines the occurrence, characteristics and transmission dynamics of ESBL-producing E. coli at the wildlife–livestock interface, with emphasis on its public health relevance and strategies for mitigation and control. The reviewed evidence indicates that livestock, wildlife and environmental matrices can be interconnected reservoirs of resistant E. coli and resistance genes. Transmission should not be interpreted as a simple linear process from livestock to wildlife or humans but rather as a bidirectional and ecological phenomenon shaped by antimicrobial use, farm management, biosecurity, wildlife ecology, environmental contamination and mobile genetic elements. Wildlife may function as a sentinel, reservoir or disperser of resistant bacteria, although detection alone does not demonstrate direct transmission. Integrated surveillance combining livestock, wildlife, food-chain and environmental sampling, supported by genomic analysis, is essential to clarify transmission pathways and guide effective control measures. Full article

Cystic echinococcosis (CE) caused by the parasite Echinococcus granulosus is a zoonotic disease of global concern. Because most African countries have not yet conducted systematic studies on CE, it is difficult to determine its exact status. However, as with any parasitic zoonotic disease, the first step in developing a comprehensive management and control strategy is to identify the host range, transmission risk factors, and national and regional epidemiological data. This review evaluated and summarized articles on CE retrieved from the PubMed and Africa Journal Online (AJOL) databases. Inclusion criteria were studies (including case reports) focused on the prevalence of CE in animals and humans between 1970 and 2025. This review revealed that although numerous early studies on CE exist, only a few were conducted in Africa from 1970 to 2025. Furthermore, data regarding population genetic composition and the role of wildlife in CE transmission remain scarce. This review systematically evaluated the prevalence and transmission of CE in Africa and identified priority areas for surveillance and control. Full article

Antimicrobial resistance (AMR) is a global health threat that continues to concern scientists because it can be driven not only by antibiotic misuse but also by environmental factors. Mining-related heavy metal pollution can apply strong selective pressure on microbial communities, leading to a significant increase and spread of antibiotic resistance genes (ARGs) in the environmental ecosystems. Here, we critically review the emerging role of mining environments as hotspots of environmental resistomes and the mechanisms by which heavy metal contamination drives co-selection of antibiotic resistance. There is also evidence that mining environments, such as AMD systems, mine tailings, contaminated sediments, and mining-impacted soils, harbor highly diverse microbiomes enriched with different resistance determinants. Heavy metals such as copper, zinc, cadmium, mercury, and arsenic promote ARG co-selection through co-resistance, cross-resistance, and co-regulation mechanisms. Widespread co-occurrence of metal- and antibiotic-resistance genes on mobile genetic elements such as plasmids, integrons, and transposons has been demonstrated in metagenomic studies. Environmental dissemination pathways, such as water systems, agricultural soils, wildlife interactions, and occupational exposure, may promote the spread of resistance genes outside mining sites. Mining ecosystems are underrecognized and potentially important reservoirs of antimicrobial resistance. This review highlights the importance of integrating environmental resistome surveillance into existing global AMR monitoring frameworks to understand underlying ecological drivers of resistance evolution. Tackling metal-driven antibiotic resistance requires innovative, solution-based interdisciplinary research, enhanced environmental screening and soil and water testing practices, and sustainable mining practices within the One Health paradigm. Full article

Rotavirus A (RVA) G3P[3] genotype is widely reported in dogs and less frequently in cats, with only sporadic human cases worldwide. All reported human infections have occurred in children, suggesting increased susceptibility likely linked to close contact with pets and age-related hygiene practices. The identification of a novel genotype constellation in Brazilian canine G3P[3] strains in 2017 prompted full-genotype characterization of the historical RVA/Human-wt/BRA/IAL-R451/2011/G3P[3] strain, previously sequenced only for VP7 and VP4, to define its genomic constellation and relatedness to canine strains. All 11 segments were analyzed by RT-PCR, sequencing and phylogenetics. The rare genotype–lineage constellation G3.III-P[3]-I2.XX-R3.II-C2.V-M3.II-A9-N2.XXIV-T3.II-E3.II-H6.I, shared with Brazilian canine strains, was identified, supporting a potential common origin. RVA/Human-wt/BRA/IAL-R451/2011/G3P[3] strain showed high genetic similarity (93.2–99%) with canine, feline and canine/feline-like human strains worldwide, with six genes (VP1, VP6 and NSP2–NSP5) closely related to Brazilian dog isolates (97.6–99%), indicating its canine origin. NSP2 clustered with strains from domestic (bovine), synanthropic (rat) and human hosts, while VP7 and VP4 were associated with wildlife (bat; raccoon dog) and environmental (sewage; river water) strains, supporting interhost reassortment and highlighting aquatic environments as reservoirs for interspecies transmission. Identification of new lineages (VP1, VP3 and NSP2) within the AU-1-like backbone reflects its underexplored diversity. This novel constellation likely circulated in dogs and may spill over to humans via close contact, reinforcing a One Health approach to understand RVA zoonotic risk, especially in hotspot regions like Brazil. Full article

Rodents and shrews are important reservoir hosts due to their close association with human activities and their role in carrying various zoonotic pathogens. Recently, meta-transcriptomic sequencing has become a powerful tool for surveilling and screening novel pathogens from wild animals. However, many of these studies focused only on the diversity and genetic evolution of viruses from wildlife, while ignoring non-viral pathogens such as bacterial and eukaryotic microorganisms. Here, we performed a comprehensive infectome analysis of 227 tissue samples collected from 42 rodents and 16 shrews across six cities of Guangdong Province, China. We identified 34 viral families, including 23 mammalian viruses. Phylogenetic analysis revealed a henipavirus from the kidneys of shrews closely related to the Langya virus with potential infection risks to humans. Additionally, two potential pathogenic bacteria and 12 eukaryotic pathogens from six genera were found, showing clearer organ tropism than viruses. Interestingly, a moderate positive abundance correlation between Usmuvirus newyorkense and Trichinella suggested a potential virus–parasite association. We used machine learning models to evaluate the zoonotic potential of the obtained viruses, which indicated that 15 of 23 viral species were high risk for human infection. These findings provide important insight into the substantial zoonotic threat posed by pathogens circulating in wild small mammals in southern China and highlight the necessity for persistent wildlife pathogen surveillance. Full article

This review provides a comprehensive overview of the genetic diversity and epidemiological potential of Yersinia pestis in Kazakhstan’s natural plague foci, emphasizing the link between genotypic variation and outbreak capacity. Integrating historical epidemiological records with contemporary microbiological and genomic data (including PCR, VNTR/MLVA, SNP analysis, and whole-genome sequencing), we evaluate core and accessory genome variations. The data reveal substantial regional heterogeneity. High-risk desert foci (Caspian and Aral regions) are dominated by the Medievalis biovar, including atypical genovariants lacking canonical markers. Conversely, high-mountain foci (Sarydzhaz, Talas) harbor the Antiqua and Talas biovars, primarily linked to enzootic circulation. Notably, the Ili River focus exhibits extreme genomic variability, featuring strains with plesiomorphic traits. Furthermore, the widespread distribution of mobile elements like the cryptic plasmid pCKF suggests significant horizontal transfer contributing to pathogen adaptation. Ultimately, Central Asian plague dynamics are driven by complex evolutionary and ecological interactions. Given climate change and expanding human–wildlife interfaces, continuous genomic and ecological surveillance is essential for the early detection of high-risk Y. pestis genovariants and improving public health preparedness. Full article

Helminth infections remain a major constraint to livestock productivity, particularly in regions where domestic animals and wildlife share grazing habitats. This study investigated the molecular diversity and transmission dynamics of helminth communities in sheep (Ovis aries) and saiga antelope (Saiga tatarica) in West Kazakhstan. A total of 35 animals (20 sheep and 15 saiga) were examined, and helminths were identified using polymerase chain reaction targeting the ITS1 region of ribosomal DNA for nematodes and the mitochondrial cox1 gene for cestodes. Of the 20 analyzed samples, 80% were successfully identified at the molecular level. Detected species included Haemonchus contortus, Trichuris ovis, Chabertia ovina, Moniezia expansa, and Avitellina centripunctata. Phylogenetic analysis revealed that Chabertia ovina isolates from both hosts clustered within a single monophyletic clade, indicating high genetic similarity and supporting potential cross-species transmission. Mitochondrial markers provided higher resolution for cestode differentiation, whereas ITS1 was effective for nematode identification. The predominance of Chabertia ovina in saiga suggests ecological adaptation and efficient transmission within wild populations. These findings highlight the epidemiological significance of shared grazing ecosystems and underscore the need for integrated parasite control strategies that consider both livestock and wildlife reservoirs. Full article

The goatpox virus (GPV) is a highly contagious pathogen primarily affecting domestic small ruminants in endemic regions of Northern Africa, the Middle East, and Asia. This study reports the first confirmed outbreak of GPV in captive wild ruminants in the United Arab Emirates (UAE). The outbreak occurred in a fenced 900-hectare mountainous reserve following a period of heavy rainfall, and Barbary sheep (Ammotragus lervia), Nubian ibex (Capra nubiana), Arabian oryx (Oryx leucoryx), and Scimitar oryx (Oryx dammah) were affected. Clinical signs included generalized cutaneous nodules, mucopurulent nasal discharge, respiratory distress, weakness, and emaciation. Over a three-month period, 71 animals died or were euthanized. Histopathological findings were consistent with GPV infection in goats, although typical inclusion bodies were missing. Real-time PCR confirmed GPV DNA in multiple tissues with a high viral genome load. Virus isolation was successful only in lamb testis cells. Whole-genome sequencing demonstrated that the isolates were genetically identical and clustered within the Central and Western Asia lineage, showing closest similarity to a Turkish field strain. The finding highlights the potential for cross-species transmission of GPV into wildlife and emphasizes the importance of surveillance, as well as molecular diagnostic and preventative vaccination strategies at the wildlife–livestock interface. Full article

Misiones, Argentina, holds one of the largest remnants of the Atlantic Forest, with almost 1.4 million hectares of native forest, representing a critical landscape for sustainable biodiversity conservation. However, connectivity across this ecoregion is increasingly threatened by habitat conversion, landscape fragmentation, and poaching pressures that extend beyond protected area boundaries, undermining long-term sustainability of wildlife populations. Using conservation detection dogs, we located, collected, and genetically confirmed 198 scats belonging to four game species: 20 lowland tapir (Tapirus terrestris), 72 white-lipped peccary (Tayassu pecari), 55 collared peccary (Pecari tajacu), and 51 Azara’s agouti (Dasyprocta azarae). Analyses examining species-specific habitat associations emphasized the importance of extending inference beyond point locations to encompass species’ home ranges, with native forest consistently identified as a key component of habitat use. The high prevalence of scats in mosaics of human-modified habitats outside protected areas, especially along their borders, underscores the importance of managing these areas as part of a broader sustainable landscape matrix. While native forest fragments outside of protected areas may serve as important refugia supporting species persistence, their contribution to sustainable management depends on reducing poaching pressure across these landscapes. There is an urgent need to expand antipoaching efforts beyond protected areas and across the Atlantic Forest in the Green Corridor of Misiones while preventing ongoing deforestation and the expansion of monoculture plantations. Achieving sustainable wildlife management in this region will require integrated strategies that promote sustainable land use, conservation planning, and rural development. Full article

The genus Trichinella comprises zoonotic nematodes infecting a wide range of carnivorous and omnivorous animals, including humans. Infection occurs through the consumption of raw or undercooked meat containing viable Trichinella larvae. Among the species within this genus, Trichinella spiralis is considered one of the most epidemiologically important due to its high reproductive capacity and its frequent association with infections in domestic animals and humans. In this study, muscle samples from 18 invasive American minks (Neovison vison) were examined for Trichinella larvae using the magnetic stirrer method. Species identification was performed via multiplex polymerase chain reaction (PCR), while the internal transcribed spacer 1 (ITS1) region was amplified to evaluate the intraspecific genetic variability. Trichinella larvae were detected in one of the 18 (5.6%) animals investigated, and all isolates were identified as T. spiralis. Ten ITS1 sequences obtained from individual larvae were 100% identical. Network and principal coordinate analyses revealed that the sequences clustered by geographic origin rather than host species and were more related to isolates from domestic pigs than to wildlife animals. These findings provide the first evidence of T. spiralis in American minks in Baltic and Scandinavian countries and contribute to a better understanding of the epidemiology of trichinellosis in the region. Full article

Hepatitis E virus (HEV) is a zoonotic pathogen of global concern that circulates in both domestic and wild swine populations. Understanding its presence and dynamics in wildlife reservoirs is crucial for assessing spillover risks and designing One Health surveillance strategies. This study investigated the occurrence, genetic diversity, and evolutionary relationships of HEV in wild boars from mainland Portugal. A total of 120 animals from seven districts were tested, with HEV RNA detected in four cases (3.3%), all from the Évora district near the Spanish border. One positive sample was successfully sequenced, and phylogenetic analysis based on the complete genome classified it within the HEV-3m subtype, clustering with predominantly human-derived sequences from Spain and France, which highlights its zoonotic potential. A second phylogenetic analysis based on a partial genomic fragment, including sequences from domestic pigs in Portugal, revealed the co-circulation of subtypes 3e, 3f, and 3m without clear spatial or temporal patterns. Phylogeographic analysis suggested that the identified strain was most likely introduced from Spain, supporting the hypothesis of cross-border transmission through wild boar movement. No recombination events were detected in the sequence obtained in this study. These findings provide the first molecular evidence of HEV-3m circulation in wild boars in Portugal, offering valuable insight into the HEV strain circulation in European wildlife populations. The zoonotic potential of HEV and the likelihood of interspecies transmission highlight the need for coordinated cross-border surveillance and integrated One Health strategies. Full article

Avian trichomonosis is caused by protozoa of the genus Trichomonas, mainly Trichomonas gallinae, which infects the upper digestive tract of birds and is commonly associated with Columbiformes, the main reservoirs of the parasite. This study aimed to investigate the occurrence and genetic diversity of Trichomonas spp. in captive synanthropic birds from southeastern Brazil. Oropharyngeal swabs were collected from 281 birds belonging to 13 avian orders and analyzed using Diamond medium culture, Giemsa-stained smears, and molecular assays. Of the 262 samples submitted to culture analysis, 72 (27.48%) showed trophozoite-like structures under light microscopy. Molecular screening based on the ITS1–5.8S–ITS2 region detected Trichomonas DNA in 76 out of 267 samples with successful DNA extraction (28.46%), including 72 Columba livia domestica from Franca, one Coragyps atratus from Ribeirão Preto, and three rock doves from Jaboticabal. Among the ITS-positive samples, 67 (88.15%) amplified the Fe-hydrogenase gene, and 65 (85.5%) were also positive for the 18S rRNA gene. Only six samples (2.29%) exhibited structures compatible with Trichomonas spp. in Giemsa-stained smears. Phylogenetic analyses based on ITS sequences grouped the isolates into two clades within the Trichomonas gallinae complex. Greater genetic diversity was observed using Fe-hydrogenase and 18S rRNA markers, revealing multiple haplotypes and clades. Molecular assays, particularly PCR applied directly to oropharyngeal swabs, showed higher sensitivity for detecting and characterizing Trichomonas gallinae compared to culture and cytology. These findings highlight the high occurrence and genetic diversity of T. gallinae in captive synanthropic pigeons and reinforce the importance of molecular tools for epidemiological surveillance in wildlife facilities. Full article

Members of the genus Brucella are bacterial pathogens of global importance, and their increasing detection in marine mammals has raised concerns for wildlife conservation and public health. In this study, we evaluated the biological and pathogenic characteristics of two Brucella sp. sequence type 27 (ST27) isolates obtained from a dwarf sperm whale (Kogia sima). We compared them with terrestrial and marine Brucella reference strains. We assessed resistance to polymyxin B and human serum complement, intracellular infection dynamics in HeLa epithelial cells, persistence in a murine model, and associated hematological and histopathological changes, and analyzed lipopolysaccharide (LPS) profiles. The Kogia isolates exhibited resistance to polymyxin B and serum complement, comparable to that of B. abortus 2308W and marine mammal Brucella strains. In HeLa cells, the isolates displayed distinct, strain-specific intracellular infection dynamics. In the murine model, both isolates persisted in the spleen and induced granulomatous lesions. However, splenic bacterial loads and histopathological scores were generally lower than those observed with B. abortus 2308W, which exhibited the highest virulence among the strains evaluated. Hematological alterations associated with Kogia isolates were also less pronounced than those induced by B. abortus 2308W, indicating an intermediate and strain-dependent virulence phenotype without evidence of enhanced virulence relative to the terrestrial reference strain. Western blot analyses showed that Brucella sp. ST27 isolates were not recognized by anti-B. abortus or anti-O-antigen monoclonal antibodies, while exhibiting a distinct recognition pattern with anti-B. canis serum, indicating differences in surface antigen composition. Comparative whole-genome analysis identified a limited number of isolate-specific variants affecting coding and intergenic regions. Collectively, these findings highlight phenotypic and genetic features of Brucella sp. ST27 from Kogia sima, which distinguishes it from other marine and terrestrial Brucella strains and supports further investigation into its biological behavior and potential public health relevance. Full article