Search Results (2,889)

Since its emergence in 2019, SARS-CoV-2 has resulted in more than 7.1 million deaths worldwide. It has been shown that co-infection with influenza A virus (IAV) can worsen clinical symptoms in COVID-19 patients and small animal models have been used to elucidate the molecular mechanisms of co-infection between SARS-CoV-2 and IAV. This study aimed to establish a co-infection model in pigs, a natural reservoir for IAV but resistant to SARS-CoV-2 infection, by determining whether pigs become susceptible to SARS-CoV-2 following a primary IAV infection. Here, pigs were primarily infected with swine influenza A virus (SIV) via the intratracheal route and, 3 days later, secondarily challenged with SARS-CoV-2. SIV was isolated from nasal swabs, and pigs seroconverted to SIV. In contrast, SARS-CoV-2 RNA was detected in nasal and oropharyngeal swabs only at day 1 post-secondary challenge, with no evidence of seroconversion against SARS-CoV-2. These data indicate that pigs are not susceptible to SARS-CoV-2 following SIV infection and therefore are not a suitable model for IAV/SARS-CoV-2 co-infection research. Full article

Bartonella henselae is a flea-borne zoonotic bacterium for which domestic cats constitute the principal reservoir. However, contemporary molecular epidemiological data from Portugal remain scarce. This retrospective laboratory study analysed EDTA-stabilised blood samples from apparently healthy cats submitted for routine screening by 74 veterinary centres across mainland Portugal and autonomous regions over an 11-year period (2015–2025). DNA extracts were tested using a species-specific TaqMan qPCR assay for B. henselae with an internal extraction control, and a subset of samples was subsequently confirmed by nested PCR followed by Sanger sequencing (ribC). Among 270 cats, 47 tested positive, yielding a qPCR prevalence of 17.4% (95% confidence interval [CI] 13.1–22.5). Submissions were predominantly from Northern Portugal, and infection status was not statistically associated with the Nomenclature of Territorial Units for Statistics (NUTS) level 2 region (p = 0.478). Infection was more frequent in younger cats (median age 2 years, interquartile range [IQR] 1–5; p = 0.037), while sex (p = 0.103) and breed (p = 0.730) were not significantly associated with infection status. These findings support endemic circulation of B. henselae in Portuguese cats at levels comparable to other temperate European regions. The detection of subclinical infection in apparently healthy cats is relevant to transfusion medicine and supports the inclusion of B. henselae qPCR screening in donor selection protocols. Full article

Tuberculosis (TB) remains a global public health emergency, with multidrug-resistant TB (MDR-TB) and rifampicin-resistant TB (RR-TB) posing critical challenges. Conventional longer regimens are characterized by suboptimal effectiveness, high toxicity, and poor tolerability. Consequently, there is an urgent demand for more effective, safer, shorter regimens with enhanced tolerability to replace traditional treatments. The present study aimed to systematically assess the effectiveness and safety of bedaquiline-containing modified shorter regimens (adaptations of the WHO-recommended 9–12-month bedaquiline-containing shorter regimen, with ethionamide, ethambutol, isoniazid, and pyrazinamide partially or fully substituted by linezolid, cycloserine/terizidone, and/or delamanid) for MDR/RR-TB. Databases (PubMed, Cochrane Library, Embase, and Web of Science) were searched up to 17 December 2025. Data on treatment success, adverse events, and patient characteristics were extracted. Heterogeneity was assessed using Cochrane Q test and I² statistic. Eleven studies involving 8166 patients were included. The pooled treatment success rate was 78.5% (95% CI: 0.69~0.87, I²: 98.45%; p = 0.00). The incidence of serious adverse events was 10.0%. Bedaquiline-containing modified shorter regimens may offer a potentially viable treatment option for MDR/RR-TB patients, giving an option for patients who are ineligible for standardized regimens. In order to verify these findings, further large-scale trials are required. Full article

Liver fibrosis induced by Schistosoma japonicum Katsurada, 1904 (S. japonicum) infection lacks effective diagnostic markers and specific anti-fibrotic therapies. Although dysregulated iron homeostasis and ferroptosis pathways may contribute to its pathogenesis, the core regulatory mechanisms remain elusive. To unravel the ferroptosis-related molecular features, this study integrated transcriptomic datasets (GSE25713 and GSE59276) from S. japonicum-infected mouse livers. Following batch effect correction and normalization, ferroptosis-related differentially expressed genes (FRDEGs) were identified. Subsequently, core hub genes were screened through the construction of a protein–protein interaction (PPI) network, functional enrichment analysis, immune infiltration evaluation, and receiver operating characteristic (ROC) analysis. The expression patterns of these hub genes were further validated in an S. japonicum-infected mouse model using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The study identified 7 hub genes (Lcn2, Timp1, Cth, Cp, Hmox1, Cbs, and Gclc) as key regulatory molecules. Functional enrichment analysis revealed that these hub genes are closely associated with sulfur amino acid metabolism and oxidative stress responses. Specifically, key enzymes involved in cysteine and glutathione (GSH) synthesis (Cth, Cbs, Gclc) were consistently downregulated, suggesting a severe impairment of the host antioxidant defense capacity. Conversely, pro-fibrotic and pro-inflammatory markers (Timp1, Lcn2, Hmox1) were upregulated. This molecular pattern was significantly associated with a remodeled immune microenvironment, characterized by increased infiltration of neutrophils and eosinophils. In vivo validation confirmed the expression trends of 6 hub genes, corroborating the bioinformatics predictions, while the discrepancy in Cp expression highlighted the complexity of post-transcriptional regulation in vivo. The identified hub genes demonstrated excellent diagnostic potential, with Timp1 achieving an area under the curve (AUC) of 1.000. This study elucidates the molecular link between S. japonicum infection and the ferroptosis pathway, suggesting that these hub genes may drive liver fibrosis progression by regulating sulfur metabolism and the immune microenvironment. These findings offer potential diagnostic biomarkers and novel therapeutic targets for schistosomal liver fibrosis. Full article

Plesiomonas shigelloides, an aquatic Gram-negative bacillus often associated with self-limiting gastroenteritis, has been reported worldwide. However, to date, no reviews have specifically investigated P. shigelloides bacteremia, which is rare and potentially fatal. This scoping review aimed to examine the existing literature to identify the epidemiology, clinical characteristics, antimicrobial susceptibility, and outcomes of P. shigelloides bacteremia. A PRISMA-ScR-guided search of PubMed, Scopus, Web of Science, and Embase identified 22 published cases, all reported as single-patient case reports. Cases were globally distributed, with the majority reported from the Americas and Europe. The median patient age was 46 years. The case fatality rate was 27.3% (n = 6/22). Most patients had identifiable host risk factors, particularly hematological disorders, neonatal status, or immunocompromised status, and environmental exposure such as raw seafood consumption or contact with freshwater. Clinical presentations were heterogeneous, commonly including fever and sepsis or septic shock. Microbiologically, P. shigelloides demonstrated consistent intrinsic resistance to ampicillin while retaining susceptibility to multiple antimicrobial classes. Poor outcomes were more closely associated with host factors and delayed presentation than with antimicrobial resistance. Early diagnosis, targeted therapy, and antimicrobial stewardship are essential for optimizing outcomes in this rare but severe infection. Full article

This study aimed to classify Escherichia coli phages using bioinformatics analysis systematically and to establish corresponding PCR and qPCR detection methods for rapid molecular typing and identification. Based on 419 complete E. coli phage genomes available in NCBI, phylogenetic and pan-genomic analyses were conducted to classify the phages at the family, subfamily, and genus levels and to identify highly conserved core genes. Specific primers targeting these core genes were designed, and their specificity, sensitivity, and reproducibility were verified using conventional PCR and dye-based qPCR. A total of 357 phages were successfully classified, encompassing 10 families, 20 subfamilies, and 67 genera. Pan-genomic analysis identified type-specific core genes within 16 taxa, including Ackermannviridae and Demerecviridae, for which 16 pairs of primers were designed. Validation using bacteriophages isolated from Xinjiang cattle farms showed distinct single PCR bands with high specificity, and the qPCR assay achieved a sensitivity of up to 10⁻⁵ µg/µL. This study established an efficient and broad-spectrum molecular typing and detection method for E. coli phages, providing a powerful preliminary screening tool for phage selection. Full article

The frequent and indiscriminate use of all classes of synthetic anthelmintics to deworm small ruminants has decreased their effectiveness in a worldwide problem of anthelmintic resistance. Using active plant metabolites with anthelmintic properties has become a suggested alternative to control parasitic helminths. The present study investigated the ovicidal and larvicidal activity of a fraction (CnF4) containing protocatechuic acid (3,4-dihydroxybenzoic acid) from Chamaecrista nictitans (Fabaceae) and a commercial standard of protocatechuic acid against strains of the parasitic nematode Haemonchus contortus susceptible (HcIVM-S) and resistant (HcIVM-R) to ivermectin, using egg hatch inhibition (EHI) and L3 larval mortality assays. The CnF4 fraction showed an EHI greater than 90% at 0.8 mg/mL against HcIVM-S and an EHI = 88.39% at 1.6 mg/mL against HcIVM-R. The commercial standard of protocatechuic acid displayed an EHI of 97.49% at 0.25 mg/mL against HcIVM-S and an EHI greater than 98% at 0.5 mg/mL. In the larval mortality assays, protocatechuic acid caused 72.4% larval mortality of HcIVM-S at 8 mg/mL and 53.2% mortality of HcIVM-R at 16 mg/mL. These results indicate that protocatechuic acid was more effective in inhibiting egg hatching and causing larval mortality against HcIVM-S compared to HcIVM-R. Full article

Background: Arthrographis spp. are environmental fungi commonly found in soil and compost. Infections caused by Arthrographis species remain an uncommon clinical occurrence. Although these infections are infrequent in the general population, their incidence appears to be elevated among immunocompromised patients or those with significant comorbidities. Objectives: This review seeks to examine all documented human cases of Arthrographis spp. infections, with particular focus on aspects such as epidemiology, microbiological features, resistance patterns, therapeutic approaches and associated mortality rates. Methods: A narrative review was performed based on data obtained from the PubMed/MedLine and Scopus databases. Results: A total of 21 articles reported Arthrographis spp. infections in 21 patients. The mean age of affected individuals was 43.62 years, with 66.6% being male. A history of trauma was the most common predisposing factor, present in 33.33% of cases. Fever and abscess formation were the predominant clinical manifestations (28.6%), followed by organ dysfunction in 19% of patients. In vitro, the yeast generally showed susceptibility to voriconazole and itraconazole, with a low rate of resistance to amphotericin B. Clinically, amphotericin B was the most frequently administered antifungal (55%), followed by voriconazole (40%) and itraconazole (30%). The overall mortality rate was 19%, while deaths directly attributable to the infection accounted for 14.3%. Conclusions: Due to the capacity of Arthrographis spp. to cause serious infections, it is important for healthcare providers to consider this organism when dimorphic yeast appears in biological specimens’ cultures, especially in patients with immunosuppression or significant underlying conditions, to facilitate timely and accurate diagnosis. Full article

Background: Pseudomonas aeruginosa is one of the leading agents causing healthcare-associated infections (HAIs) due to its intrinsic resistance, its capacity to acquire resistance mechanisms, and its persistence in hospital environments. In Mexico, it ranks among the most frequently reported pathogens in national surveillance systems. The aim of this study was to characterize antimicrobial resistance profiles and the genetic determinants associated with MDR/XDR phenotypes in P. aeruginosa strains from HAIs at Hospital Juárez de México (HJM). Methods: Sixty-three strains from patients with HAIs were analyzed. Identification was confirmed by 16S rRNA gene sequencing. Antimicrobial susceptibility testing followed CLSI guidelines. MDR/XDR phenotypes were classified according to the Latin American consensus for categorizing MDR, XDR, and PDR pathogens. Screening for resistance mechanisms was carried out by PCR for the main β-lactamases circulating at HJM. Finally, mutations in the oprD gene were detected in imipenem-resistant isolates through amino acid sequence alignment. Results: Resistant phenotypes allowed the identification of MDR and XDR profiles. Only the metallo-β-lactamase bla_VIM was detected. Analysis of oprD porin sequences revealed recurrent mutations (S103T, T115K, L170F, G186P, and T189V) associated with imipenem resistance. Conclusions: In P. aeruginosa, the presence of bla_VIM and structural alterations in OprD confirms the multifactorial nature of carbapenem resistance. These findings underscore the need to strengthen microbiological surveillance programs and antimicrobial stewardship strategies to mitigate the impact and spread of MDR/XDR isolates. Full article

Urinary tract infections (UTIs) and urolithiasis exhibit a complex bidirectional relationship in which microbial colonization and urinary obstruction may mutually reinforce each other. This retrospective observational study evaluated clinical and microbiological factors associated with UTI in patients with urolithiasis using a large institutional dataset. A total of 23,241 urine cultures obtained from 12,708 unique patients were analyzed, comparing individuals with and without urolithiasis. In stone-forming patients, demographic variables, urine pH, hydronephrosis, ureteral double J stent presence and indwelling duration, urinary anomalies, and stone characteristics were assessed. Logistic regression identified independent associations, and ROC analysis defined optimal risk thresholds. UTI were more frequent in the stone group (34.5%) compared with non-stone forming patients (28.9%, p < 0.001). Escherichia coli was the most common uropathogen overall, whereas Klebsiella pneumoniae, Enterococcus faecalis, and Pseudomonas aeruginosa were significantly enriched in patients with stones. Elevated urine pH (OR: 6.37; CI: 2.67–15.19; p = 0.001) and hydronephrosis (OR: 9.14; CI: 3.74–22.35; p = 0.001) were independently associated with UTI. A stent dwell time above 29.5 days was associated with infection with 85% sensitivity and 54% specificity (AUC: 0.70; CI: 0.68–0.73), and urine pH 6.2 or higher was associated with infection with 86% sensitivity and 67% specificity (AUC: 0.77; CI: 0.75–0.80). These findings underscore that urine alkalinity, obstruction, and prolonged stenting are key factors associated with infection risk, supporting the need for careful stent management and timely microbiological evaluation in patients with urolithiasis. Full article

Investigating the prevalence and molecular genetic characteristics of Anaplasma ovis, Theileria spp., Anaplasma phagocytophilum, and hemotropic Mycoplasma infections in sheep populations across different regions of Gansu Province is of significant importance for the prevention and control of these pathogens. A total of 1523 sheep blood samples were collected from 19 counties (districts) in Gansu Province. Pathogen screening was conducted using PCR-based molecular detection techniques, followed by sequencing and phylogenetic analysis of specific genes (e.g., Msp4, 18S rRNA) from selected positive samples. Blood-borne pathogens infections in Gansu Province were widespread but unevenly distributed geographically. Theileria spp. and Anaplasma ovis were the dominant pathogens, with overall infection rates of approximately 16.7% and 9.6%, respectively. The highest Anaplasma ovis infection rate (82.5%) was observed in the Gannan region, where co-infections were common (24/97). An exceptionally high Theileria spp. infection rate (87.5%) was detected in the Zagana area. No pathogens were detected in Wuwei, Jingyuan, Huining, Jingtai, Qinghuan, or Maqu. Phylogenetic analysis revealed that the Msp4 gene sequences of Anaplasma ovis isolates from Gansu shared 99.48% homology with strains from Europe, Asia, and Africa. Anaplasma phagocytophilum isolates also showed high homology (99.53–99.84%) with multiple global strains. Seasonal data indicated significantly higher Theileria spp. infection rates in spring (23–34%) compared to other seasons (approximately 12%). Gansu Province is an endemic area for multiple blood-borne pathogens, with distinct regional clustering and seasonality in prevalence. The high conservation of pathogen gene sequences suggests genetic stability. This study provides essential epidemiological baseline data and a scientific foundation for targeted prevention and control of blood-borne pathogen diseases in sheep in Gansu Province. Full article

This comprehensive review examines pathogens affecting adult anadromous Pacific salmon (Oncorhynchus spp.) during their terminal freshwater migration and spawning across populations from California through Alaska, including Oregon, Washington, and British Columbia. We systematically reviewed selected pathogens based on their significance to adult salmon health or role in epizootiology, categorizing them by their impact on prespawn mortality (PSM), disease severity, and maternal or ‘egg-associated’ transmission risks to progeny. Our analysis encompasses macroparasites, microparasites, bacteria, and viruses affecting anadromous Pink (O. gorbuscha), Chum (O. keta), Coho (O. kisutch), Sockeye (O. nerka), and Chinook Salmon (O. tshawytscha) and Steelhead Trout (O. mykiss), integrating extensive literature analysis with direct field observations and case studies from representative geographic regions. Understanding pathogen impacts during the spawning life stage is crucial for salmon population sustainability, as the unique semelparous nature of Pacific salmon makes this terminal phase critical for reproductive success and the continuation of these ecologically, economically, and culturally vital species. Full article

Tularemia is a well-known zoonotic disease around the world, with particularly high rates in certain geographic areas of the U.S. Though the disease is regularly reported, it is classified as a rare condition owing to the relatively low number of cases detected annually. Interestingly, however, the number of cases in the U.S. has shown a positive upward trend through time. The aim of this study was to summarize, interpret, compare, and contextualize temporal trends in tularemia epidemiology at the national scale within the U.S. utilizing long-term data sets encompassing the 23-year span from 2000 to 2022. We used two secondary data sets: (1) case data reports from the National Notifiable Disease Surveillance System (NNDSS) of the Centers for Disease Control and Prevention (CDC) and (2) the National Inpatient Sample (NIS) of hospitalization discharge records. In addition to investigating patterns, we were interested in the utility of using hospital discharge records as a means of indirect epidemiological surveillance of this rare disease. Both data sets highlight the high variability in annual cases through time but underscore the highest risk of disease among patients classified as White and male, as well as the extraordinarily high rates among American Indian/Alaska Native populations, particularly those with pulmonary tularemia disease. Descriptive epidemiological summaries and statistical comparisons are provided across the time series for sex, age, ethnoracial identity, and geography; hospitalization characteristics are also described. Our desire to use case rates from hospitalization records as a surrogate for CDC case incidence rates did not provide the desired precision, though hospital discharge records do provide valuable and useful information necessary to estimate general high-risk groups for tularemia through time. Full article

The skin of bats hosts diverse microbial communities, yet most research has focused on bacteria or single fungal pathogens such as Pseudogymnoascus destructans. Here, we present the first direct comparison of culturable skin mycobiota in the greater mouse-eared bat (Myotis myotis) between hibernation and the reproductive season. Swabs collected from hibernating bats in the Nietoperek reserve and from maternity colonies in Lipy yielded 41 fungal species, including 27 that represent new records for M. myotis. Winter assemblages were less diverse but strongly dominated by Penicillium (>90% of isolates), while summer maternity roosts supported broader communities shaped by environmental exposure and plant-associated fungi. Despite seasonal turnover, a small set of taxa, including Aspergillus fumigatus, Mucor fragilis, and Pseudogymnoascus pannorum, persisted across both seasons, indicating the presence of a limited core mycobiota. Richness was higher on wing membranes than on tail membranes, whereas biometric variables such as sex, age, body mass, and forearm length showed only weak and inconsistent associations with fungal diversity. These findings demonstrate that seasonal filtering is likely one of the main factors determining the skin mycobiota in M. myotis. Additionally, we expand the known fungal diversity of this species, and emphasize its role as a reservoir of environmental, opportunistic, and pathogenic fungi. Full article

Anthropogenic pressures in the Amazon Basin are reshaping human–animal–environment interactions and increasing zoonotic disease risk. Within this One Health context, domestic dogs and cats are underrecognized contributors to pathogen circulation at the human–wildlife interface. We conducted a PRISMA-compliant systematic review of zoonotic pathogens reported in companion animals across Amazonian territories in nine countries, including literature published between 2000 and 2025 in four languages. Zoonotic pathogens showed a heterogeneous yet widespread distribution, with parasitic infections, particularly Leishmania spp., Toxoplasma gondii, and vector-borne protozoa, being the most frequently reported. A pronounced geographic bias was evident, with studies concentrated in Brazil and selected areas of the western Amazon, while large portions of the Basin remain understudied. Methodological limitations included reliance on cross-sectional designs and heterogeneous diagnostic approaches, often based solely on serology. These findings highlight the need to strengthen One Health-oriented governance frameworks that integrate animal health surveillance into environmental and public health policies. Priority actions include expanding surveillance to underrepresented regions, harmonizing diagnostic protocols, investing in regional laboratory capacity, and promoting community-based monitoring. Strengthened cross-sectoral and transboundary coordination is essential to reduce zoonotic risk and support evidence-based disease prevention in Amazonian ecosystems. Full article