Search Results (2,079)

Schistosomiasis, a neglected tropical disease (NTD), affects humans and leads to considerable clinical morbidity and severe long-term sequelae. Laboratory diagnostics for Schistosoma mansoni are mainly based on microscopic identification of eggs in stool, but sensitivity varies with infection intensity. Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) is the gold standard for bacterial identification in high-income countries. Here, we first evaluate the capacity of MALDI-TOF MS and our existing ‘in-house helminths’ database for the identification of S. mansoni worms and eggs. A subset of adult worms and egg samples was used to generate MALDI reference spectra, which were added to the database and evaluated by blind-test identification. Subsequently, egg-free human stool was spiked with purified S. mansoni eggs and analyzed by MALDI-TOF MS. Log score values (LSVs) were employed to assess the reliability of identification. A total of 62/90 (68.9%, 95% confidence interval (CI): 58.3–78.2%) adult samples were correctly identified. After database expansion, 90/90 (100%, 95% CI: 96.0–100%) and 59/60 (98.3%, 95% CI: 91.1–100%) were correctly identified for adult worms and purified eggs, respectively. In contrast, the analysis of 35 human stool samples spiked with S. mansoni as eggs did not yield identifiable spectra. MALDI-TOF MS can be applied for the identification of isolated adult S. mansoni worms and eggs. Further investigations and optimization are necessary before potential application to clinical samples (e.g., for egg detection in stool). Full article

The occurrence of the European brown hare (Lepus europaeus Pallas 1778) has declined throughout Europe in recent years. However, it remains economically valuable as an important game species. To date, information on the individual microbiota of the European hare has been limited. The phylum Firmicutes (Bacillota) was dominant, and enterococci belong to this phylum. However, they can carry virulence factor genes. Therefore, this study aimed to address two aspects: the health of hares due to their recent decline, and, as a game animal, the protection of consumers’ health. Based on MALDI-TOF mass spectrometry, five strains were identified as Enterococcus faecium and two as E. faecalis; these findings were confirmed by genotyping using PCR and phenotypic analysis. The average value of lactic acid production was 0.680 ± 0.005 mmol/L. The strains lacked the virulence factor genes esp, agg, and gelE. However, they showed susceptibility to antibiotics and to postbiotic substances, even to 13 of 14 tested. PS/Ent M appears to be the most active PS against tested strains, with inhibitory activity of 25,600 AU/mL. Postbiotic substances represent a new tool for preventing unwanted microbiota in game animals. Full article

Background/Objectives: Pet birds are increasingly recognized as potential reservoirs of zoonotic and antimicrobial-resistant bacteria, raising concerns within the One Health framework. However, data on bacterial diversity and resistance profiles in clinically affected ornamental birds remain limited. Methods: This study, conducted over three years (November 2022–March 2026), included 198 pet birds presenting with digestive and respiratory disorders. From these birds, clinical samples were analyzed bacteriologically; resulting isolates were identified by MALDI-TOF mass spectrometry, and antimicrobial susceptibility assessed using the Kirby-Bauer disk diffusion method according to EUCAST and CLSI guidelines. Results: Bacterial growth was detected in 87.9% of cases, yielding 249 distinct isolates. Gram-positive cocci predominated (62.3%), led by Staphylococcus spp. (33.3%) and Enterococcus spp. (9.6%), while Escherichia coli (9.2%) was the primary Gram-negative species. At the genus level, Staphylococcus spp. demonstrated high susceptibility to amikacin (88.5%) but significant resistance to gentamicin (75.6%) and oxytetracycline (63.6%). In contrast, Escherichia spp. isolates were largely resistant, showing only 50% susceptibility to enrofloxacin and 40% to doxycycline, with resistance to tylosin reaching 90%. Overall, 57% of isolates were multidrug-resistant, with Staphylococcus spp. contributing most to this burden. Conclusions: These findings characterize clinically ill pet birds as significant carriers of multidrug-resistant bacteria, highlighting the need for routine diagnostics and improved antimicrobial stewardship in avian medicine. Full article

Staphylococcus aureus is a common opportunistic pathogen in rabbits and may cause localized or systemic infections that affect animal health and farm productivity. The present study aimed to investigate the clinical evolution, pathological lesions, and antimicrobial susceptibility profile of S. aureus infections in rabbits raised under traditional extensive systems in Western Romania. A total of 251 rabbits from 11 holdings located in Arad, Timiș, and Caraș-Severin counties were evaluated through epidemiological investigation, clinical examination, necropsy, and bacteriological analysis. Samples were cultured on Brain Heart Infusion medium and 5% sheep blood agar, and isolates were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Antimicrobial susceptibility testing was performed using an automated system (VITEK 2, bioMérieux) and interpreted according to EUCAST guidelines. Among the examined animals, 68 rabbits (27.1%) showed clinical lesions compatible with S. aureus infection. The most common manifestations included subcutaneous abscesses, otitis externa, rhinitis, mammary abscesses, pyometra, and dental abscesses. Necropsy revealed suppurative and septicemic lesions affecting multiple organs. Antimicrobial susceptibility testing indicated high resistance to penicillin (100%), tetracycline (76.5%), doxycycline (67.6%), and amoxicillin (63.2%). In contrast, florfenicol (69.1% susceptible), ciprofloxacin (61.8%), gentamicin (54.4%), and enrofloxacin (52.9%) showed better antimicrobial activity. The results confirm the clinical and microbiological relevance of S. aureus infections in rabbits raised under traditional conditions and highlight the need for improved biosecurity measures and rational antimicrobial use. Full article

Southeast Asia (SEA) faces persistent gaps in regional understanding and control of ticks and tick-borne diseases (TBDs) despite recent advances (2023–2025). The second international symposium on ticks and TBDs in SEA (Singapore, August 2025), following the inaugural 2023 meeting in Cambodia, served as a catalyst for regional exchange that informed this perspective. SEA’s ecological and host diversity supports complex tick–host–pathogen networks, yet evidence remains fragmented due to uneven sampling that has largely focused on livestock and peri-urban environments. Key constraints include limited taxonomic resolution driven by outdated or incomplete identification keys, under-sampling of soft ticks (Argasidae), and the absence of harmonized, open-access regional reference resources (including DNA barcodes and MALDI-TOF MS spectral databases). While MALDI-TOF MS, proteomics, AI-assisted identification, and next-generation sequencing/metagenomics are increasingly applied, their broader regional uptake is limited by the absence of harmonized, open-access reference resources (including DNA barcodes and MALDI-TOF MS spectral databases). Broad ecological surveys and integrated animal and human surveillance remain limited, and vector competence studies are constrained by the scarcity of SEA-derived tick colonies and cell lines. Regional data and recent findings (2024–2026) confirm circulation of multiple TBPs (including Anaplasma, Babesia, Borrelia, Coxiella, Ehrlichia, Rickettsia, and Theileria) and highlight emerging viral findings, including southward reports of Bandavirus dabieense. Human infestations and non-communicable tick bite outcomes (e.g., tick paralysis and alpha-gal syndrome) are recognized but remain under-reported due to low clinical awareness and limited diagnostics. Importantly, the diagnostic chain is further disrupted by missed/insufficient specimen collection at the point of care, and by constrained capacity to identify (especially immature) ticks to species level—limitations compounded by the absence of harmonized, open-access regional reference resources. The symposium identified six priorities: (1) full completion and regional validation of tick identification keys for adults (in progress) and immatures (to be initiated), plus an open-access DNA barcode library anchored by curated, voucher-based collections from all SEA countries; (2) harmonization of molecular and proteomic diagnostic platforms, including expansion of regional MALDI-TOF MS and NGS protocols and reference databases; (3) development of tick colonies and cell lines from locally prevalent species to support vector competence, vaccine, and acaricide testing; (4) expansion of One Health surveillance with enhanced ecological sampling at wildlife–livestock–human interfaces; (5) establishment of open-access, region-wide data platforms for integrated tick, TBP, and ecological metadata sharing; and (6) sustained investment in human resources, training, and policy advocacy to raise research and public health visibility of ticks and TBDs. Full article

Bacteria associated with unhatched sea turtle eggs remain poorly characterized at the genomic level. This study provides genome-scale characterization of bacterial isolates recovered from unhatched green sea turtle (Chelonia mydas) eggs at Akyatan Beach—a critical nesting site in the Eastern Mediterranean. Sampling 30 nests during the nesting season, we isolated bacteria from infected eggshells and dead embryos. Following Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry(MALDI-TOF MS) identification and 16S rRNA validation, we performed whole-genome sequencing (WGS) on Citrobacter farmeri and Enterobacter cloacae, two opportunistic pathogens of significant clinical and ecological concern. High-quality draft genomes revealed remarkable metabolic versatility, particularly within carbon and nitrogen pathways. Most notably, we identified extensive resistomes including resistance to $\beta$-lactams, fluoroquinolones, and aminoglycosides, alongside virulence factors for adhesion and iron acquisition. ANI analysis confirmed high genomic similarity to clinical reference strains, comparative genomic analysis revealed a substantial accessory gene pool, suggesting potential genomic flexibility between the two isolates. These findings provide the first genome-scale insight into these pathogens in C. mydas nests, and highlighting their genomic potential for opportunistic pathogenicity. Our results advocate for integrating genomic microbial surveillance into nesting beach management through a ‘One Health’ lens. Full article

Background: Staphylococcus pseudintermedius is a major opportunistic pathogen of dogs and the primary cause of canine pyoderma and other infections. The global emergence of methicillin-resistant S. pseudintermedius (MRSP) represents a significant challenge in veterinary medicine due to its frequent multidrug-resistant phenotype and limited therapeutic options. Methods: We describe the phenotypic and genomic characterization of an MRSP isolate recovered from a vaginal swab of an 11-year-old dog diagnosed with vulvovaginitis in southern Italy. Antimicrobial susceptibility testing was performed using broth microdilution according to CLSI VET01S guidelines. Whole-genome sequencing was conducted to determine sequence type and antimicrobial resistance determinants. Results: The isolate was identified as S. pseudintermedius by MALDI-TOF MS and confirmed by genomic analysis. Multilocus sequence typing assigned the strain to sequence type ST2333. Phenotypically, the isolate exhibited multidrug resistance, including resistance to β-lactams, macrolides, lincosamides, tetracyclines, aminoglycosides, fluoroquinolones, and trimethoprim–sulfamethoxazole, while remaining susceptible to amikacin, rifampicin, florfenicol, and vancomycin. Whole-genome sequencing confirmed the presence of mecA and additional resistance determinants consistent with the observed phenotype. Conclusions: This report suggests the possible occurrence of an MDR MRSP ST2333 lineage in southern Italy and highlights the importance of combined phenotypic and genomic surveillance to support antimicrobial stewardship in veterinary medicine within a One Health framework. Full article

V. alginolyticus (VAlg) is one of the three Vibrio species causing human vibriosis. Its presence in shellfish constitutes a potential health risk. Thus, this investigation aimed to determine the prevalence and distribution of VAlg in 18,544 shellfish across geographies using standard protocols and random intercepts/mixed-effects regressions. The global VAlg prevalence in shellfish was 19.70% (95% CI: 13.54–27.75). VAlg pooled prevalence was significantly different (p < 0.0001) by shellfish type (${\chi }_{20}^2$ = 238.48), species (${\chi }_{74}^2$ = 440.34), genus (${\chi }_{51}^2$ = 414.37), VAlg detection methods (${\chi }_{10}^2$ = 150.43), nation (${\chi }_{30}^2$ = 632.27), and continent (${\chi }_4^2$ = 33.81). Europe and South America showed the highest pooled VAlg contaminated rates in shellfish (27% and 32%, respectively) but Asia had a low rate (~4%). By shellfish type, gastropods (snails) topped the list with 50%, followed by bivalves (29%). Among shellfish species, the VAlg rate declined from 67% to 5% (k ≤ 6), but with a more stable prevalence in Litopenaeus vannamei (19.02%, k = 11) and Crassostrea gigas (15.18%, k = 9). Edible oysters and clams had lower VAlg pooled rates (4–15%). Targeted culture with MALDI-TOF or species-specific qPCR detected VAlg in 100% of tested shellfish samples. By contrast, conventional phenotypic tests detected less VAlg in shellfish yielding 20% by general biochemical/API tests, 8.8% by generic PCR, and near-zero (0.3–3%) by multiplex PCR or MALDI-TOF/PCR. Both the multiplicative (${\beta }_0=-3.28\pm 3.76, F_{54;125}$ = 3.01, p = 0.001) and additive (${\beta }_0=-1.89\pm 1.47, F_{31;148}$ = 3.83, p = 0.001) interactions of nation and sample size explained 73.14% and 58.04% of the true variance in VAlg prevalence in shellfish. Other factors include detection techniques ($R^2$ = 46.59%, ${\beta }_0=-1.63\pm 0.83, F_{10;169}=11.16$, p = 0.001), nation ($R^2=37.72$ = 1.89, p = 0.006), medium $R^2$ = 19.42%, ${\beta }_0=2.24\pm 1.85, F_{15;164}$ = 1.69, p = 0.03), shellfish type ($R^2$ = 16.99%, ${\beta }_0=-3.90\pm 1.32, F_{20;159}$ = 1.34, p = 0.12), and continent ($R^2$ = 15.29%, ${\beta }_0=-1.81\pm 0.41, F_{4;175}$ = 5.90, p = 0.001). In conclusion, the study reveals substantial occurrence of VAlg in shellfish worldwide, with notable regional and species-specific hotspots. Harmonized and molecular-based surveillance of VAlg in shellfish linked to food safety criteria will be essential to manage its emerging threat. Full article

Despite its clinical importance, Staphylococcus aureus colonization in community populations remains insufficiently understood. This study aimed to determine the prevalence, anatomical distribution (nasal versus throat), and antimicrobial resistance patterns of Staphylococcus aureus colonization in healthy community-dwelling adults and to identify demographic and clinical factors associated with carriage. A cross-sectional study was conducted among 100 community-dwelling adults in Germany, yielding 200 nasal/throat samples. Staphylococcal isolates were identified using MALDI-TOF MS, and antimicrobial susceptibility was determined according to EUCAST guidelines. MRSA and PVL genes were assessed using molecular assays, and genetic relatedness was evaluated by rep-PCR. Associations with demographic and clinical variables were analyzed using multivariable logistic regression in R. Staphylococcus aureus carriage prevalence was 39%, higher in the nose (33%) than the throat (19%), with rare MRSA (3%) and no PVL detection. Significant nasal–throat discordance was observed (p < 0.01), with a fair agreement between sites (κ = 0.34). Resistance patterns among Staphylococcus aureus isolates were dominated by penicillin G resistance (47%), while 35% remained fully susceptible, and multidrug resistance was rare (6%). Multivariable analyses indicated no strong associations between overall, nasal, or throat carriage and age, sex, recent antibiotic use, or other clinical exposures (p > 0.05), with wide confidence intervals, potentially reflecting limited statistical power and only modest model discrimination (AUC 0.65–0.68). These findings indicate that community Staphylococcus aureus colonization is potentially marked by modest prevalence, substantial anatomical discordance, and a low-risk resistance profile, while common demographic and clinical factors contributed little to explaining carriage patterns. Full article

Lactic acid bacteria are important components of the early gut microbiota in piglets and may contribute to gastrointestinal stability and control of enteric pathogens, particularly under increasing restrictions on antibiotic use in livestock production. This study aimed to perform in vitro phenotypic screening and characterization of lactic acid bacteria isolated from feces of suckling piglets aged 7–28 days. A total of 42 fecal samples were collected and cultured on selective media, yielding 318 colonies, of which 135 Gram-positive, rod-shaped, catalase-negative isolates were selected for further evaluation. These isolates were assessed for tolerance to acidic conditions (pH 2.0–3.1), bile salts (0.3–0.5%), cell surface hydrophobicity, hemolytic activity, and antibacterial activity against Escherichia coli and Staphylococcus aureus. Among the tested isolates, only two (PMvet212 and PMvet318) demonstrated limited tolerance to acidic and bile conditions and exhibited moderate antibacterial activity, with inhibition zones of approximately 10–12 mm. Identification using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry indicated that PMvet212 was closely related to Lactobacillus brevis, whereas PMvet318 was identified at the genus level as Lactobacillus sp. However, both isolates exhibited α-hemolytic activity and therefore did not meet the safety criteria required for probiotic application. In conclusion, although piglet-derived lactic acid bacteria may exhibit certain functional properties, the present findings highlight that probiotic potential is strain-specific and that rigorous multi-step screening, together with further in vivo validation, is essential before practical application can be considered. Full article

Background: Acinetobacter baumannii is a non-fermenting Gram-negative bacillus responsible for severe nosocomial infections, particularly in intensive care units (ICUs). The increasing prevalence of multidrug-resistant (MDR) and carbapenem-resistant A. baumannii (CRAB) strains has become a significant challenge for infection control and antimicrobial therapy worldwide. Objectives: This study aimed to analyze the antimicrobial susceptibility patterns of clinical A. baumannii isolates recovered from a multi-profile hospital in years 2020–2024 in Lodz, Poland. Methods: Clinical isolates from various specimen types (blood, urine, wound swabs, biopsies, sputum, and bronchoalveolar lavage fluid) were obtained during routine microbiological diagnostics. Identification was performed using MALDI-TOF MS. Antimicrobial susceptibility testing (AST) was conducted using the automated VITEK^®2 system with EUCAST/CLSI interpretive criteria. Minimum inhibitory concentrations (MICs) for colistin were determined by broth microdilution. Carbapenemase production was assessed using the Carbapenem Inactivation Method (CIM) and immunochromatographic assays for OXA-23, OXA-40/58, and NDM detection. Results: A total of 244 A. baumannii isolates were recovered over the study period. Susceptibility to carbapenems (meropenem, imipenem) declined markedly, with resistance exceeding 90% by 2023–2024. Aminoglycosides exhibited variable activity, with gentamicin demonstrating the highest susceptibility rates (up to 88% in 2022). Resistance to ceftazidime and cefepime remained consistently high (>90% in 2023–2024). No fully susceptible isolates were identified for ciprofloxacin. Conclusions: The high prevalence of CRAB strains highlights the urgent need for effective infection control measures, optimized antimicrobial stewardship, and consideration of novel treatment options in the clinical setting. Full article

C. difficile is a major cause of antibiotic-associated diarrhea and hospital-acquired infections, although increasing community-acquired cases suggest alternative transmission routes. Livestock, particularly pigs, have been proposed as potential reservoirs. This study aimed to investigate the presence of zoonotic ribotypes in piglets from Tenerife (Spain) and to assess their pathogenic potential by detecting toxin genes. A total of 140 samples were analyzed, including 58 fecal samples from slaughtered piglets (4–8 weeks old) and 82 rectal swabs from piglets aged 2–25 days. Samples were cultured, identified by MALDI-TOF MS, and characterized by PCR ribotyping and toxin gene detection. No isolates were obtained from fecal samples collected at slaughter, whereas 14 (17%) rectal swabs were positive. Colonization was strongly age-dependent, with the highest prevalence at 2 days of age (100%), decreasing by day 9 (10.7%), and absent after 21 days (p < 0.05). All isolates were ribotype RT033 with a tcdA⁺/tcdB⁻/cdtA⁺/cdtB⁺ profile. The exclusive detection of RT033, a clade V lineage linked to animal reservoirs and occasional human infections, suggests a potential zoonotic risk, especially for farm workers. These findings reinforce the need for integrated C. difficile surveillance under a One Health framework to monitor emerging ribotypes and their role in community-acquired infections. Full article

Polluted mangroves are ecologically sensitive habitats that provide ecosystem services. In a selected polluted forest of Simaisma, viable aerobic, halophilic, and heterotrophic hydrocarbon-degrading bacterial strains were isolated from both rhizosphere and non-rhizosphere regions. The chemical composition of sediment showed a clear distinction between the rhizosphere and non-rhizosphere sites, as well as coastal and non-coastal sediments, as per Principal Component Analysis (PCA) clustering. Anthracene, an indicator of oil pollution, was present along with vanadium, another marker of oil pollution. Through selective enrichment cultures, a total of 25 hydrocarbon-degrading bacterial strains were isolated, including Lysinibacillus xylanilyticus, Bacillus cereus, Lysinibacillus sphaericus, Pseudomonas stutzeri, Acinetobacter calcoaceticus, and Staphylococcus warneri. To link the adaptation of bacteria to sediment chemistry, nine B. cereus strains were investigated using their MALDI-TOF MS protein profiles combined with their dendrogram. The relationship between protein profiles of B. cereus strains with their biosurfactant production capabilities was explained by a tanglogram. The tanglegram suggests that biosurfactant production is an important functional trait in B. cereus, but it is not consistently reflected in the overall protein profile. This suggests that bacterial adaptation in the polluted mangrove sediments may involve changes at multiple cellular levels, including metabolic activity and variation in protein expression profiles. These findings confirm the involvement of mangrove-associated bacteria in the sustainability of mangrove forests by promoting bioremediation of oil pollution, thereby protecting coastal ecosystems and their environmental and socio-economic aspects. Full article

Tropodithietic acid (TDA) is a sulfur-containing secondary metabolite with pronounced antimicrobial activity that has been primarily described in marine Alphaproteobacteria of the Roseobacter clade. Despite extensive studies of these bacteria, the occurrence and genetic organization of the TDA biosynthetic pathway in other bacterial groups remain poorly understood. In this study, we report the production of TDA by the freshwater bacterium Janthinobacterium sp. PLB04 isolated from diseased cell cultures of the primmorphs from the Baikal sponge Lubomirskia baikalensis. The presence of a TDA biosynthetic gene cluster homologous to the canonical tda operon previously described in the marine Roseobacter clade was found in Janthinobacterium sp. PLB04 by genome mining with bioinformatic analysis. However, comparative analysis of the cluster architecture demonstrated the absence of the gene tdaC in the Janthinobacterium sp. PLB04 genome. Despite this difference, the strain retained the ability to synthesize TDA. TDA was extracted from the culture medium and identified using chromatographic and MALDI-TOF mass spectrometric analysis. These results suggest that tdaC may not be strictly required for TDA biosynthesis in this strain and may be functionally replaced with alternative enzymatic steps or functional redundancy within the pathway. The discovery of TDA production in a freshwater Janthinobacterium strain expands the known phylogenetic and ecological diversity of TDA-producing bacteria and provides new insights into the plasticity of the TDA biosynthetic gene cluster. Full article

Protein profiling generated by MALDI-TOF (matrix-assisted laser desorption ionization-time-of-flight) was used to distinguish meat from different livestock species and identify meat species. Meat proteins from fresh beef (n = 12), pork (n = 7), chicken (n = 5) and tilapia fish (n = 3) were extracted and analyzed in a MALDI Biotyper mass spectrometer (Bruker Daltonics, Bremen, Germany) with alpha-cyano-4-hydroxycinnamic acid as the matrix. Mass spectra allowed the distinction of meat species, including between Nellore and Angus bovine breeds, and PCA classification revealed possible biomarkers for meat types. Our results corroborate MALDI-TOF mass spectrometry as an interesting tool for meat identification, which is useful for quality control and the certification of meat products. Full article