Search Results (11)

Salmonella is a globally important pathogen and one of the World Health Organization and One Health priority organisms. Reptiles represent environmental reservoirs of Salmonella serovars that can cause reptile-associated salmonellosis (RAS) in humans. Due to distinct biochemical features and uncommon O and H antigen variants, reptile-associated isolates may be difficult to identify using standard microbiological diagnostics. This study analyzed 62 Salmonella isolates obtained from wild and kept snakes in Poland. Samples originated from Natrix natrix, N. tessellata, Coronella austriaca, Zamenis longissimus, Elaphe dione and Nerodia fasciata species. Serovar prediction using SeqSero1.2 was compared with classical slide agglutination. Seventeen serovars were confirmed, with S. enterica subsp. diarizonae (IIIb) 38:r:z being the most frequent. For seven isolates, molecular and serological results were inconsistent. Among three isolates from Coronella austriaca predicted as IIIb 38:z₁₀:z₅₀, three distinct second-phase flagellar phenotypes were detected. Slide agglutination confirmed the presence of serovar 38:z₁₀:z₆, which has not been previously listed in the White–Kauffmann–Le Minor scheme or described in the scientific literature. The findings highlight the utility of genetic serovar prediction while emphasizing the need for continuous validation, particularly for the identification of rare or atypical Salmonella serovars associated with reptiles. Full article

Background/Objectives: Salmonella enterica is a major cause of foodborne infection globally, with poultry acting as an important reservoir. However, data from Central Asia remain limited. This study provides preliminary phenotypic and genomic characterization of S. enterica isolates recovered from poultry farms in southern Kazakhstan, focusing on antimicrobial resistance (AMR), serotypes/sequence types and phylogenetic relationships. Methods: In October 2024, 335 poultry and environmental samples were collected from three regions of southern Kazakhstan using a cross-sectional, detection-focused sampling strategy. Isolation of Salmonella enterica followed enrichment and selective culturing, with confirmation by biochemical assays, slide agglutination serology and real-time PCR. Antimicrobial susceptibility testing was performed using the Kirby-Bauer disk diffusion method and interpreted according to CLSI veterinary breakpoints (VET01/VET08) and CLSI M100 where veterinary criteria were unavailable. Whole-genome sequencing (Illumina) was used for in silico serotyping, MLST, AMR gene detection, plasmid replicon typing and SNP-based phylogenetic reconstruction. Results: Nine S. enterica isolates were confirmed (overall yield 2.7%; 9/335), comprising S. Enteritidis (ST11; n = 4), S. Infantis (ST32; n = 3) and ST68 (n = 2; Choleraesuis/Paratyphi C lineage). All isolates were resistant to ciprofloxacin, and most displayed resistance to ampicillin, gentamicin and trimethoprim-sulfamethoxazole. Plasmid-associated AMR determinants, including blaTEM-116, tet(A), sul1 and dfrA14, were frequently identified on IncF-type replicons. Phylogenetic analysis revealed that the isolates clustered with previously described Eurasian poultry-associated lineages. Conclusions: In this small, exploratory sample from poultry farms in southern Kazakhstan, all recovered S. enterica isolates were multidrug-resistant, with universal fluoroquinolone resistance and frequent plasmid-borne AMR genes. These preliminary findings provide baseline genomic evidence and highlight the need for broader, harmonized AMR surveillance in the regional poultry sector. Full article

Escherichia coli is a significant cause of Neonatal Calf Diarrhoea (NCD). Its extensive antigenic diversity, coupled with the ability to acquire antimicrobial resistance determinants, hampers treatment effectiveness and compromises the control measures. This study investigated the link between the presence of multidrug-resistant (MDR) E. coli and virulence factors (VFs) in NCD from central France (Departments of Cantal, Haute-Loire, Loire, and Puy-de-Dôme), between 2016 and 2022. E. coli was identified at TERANA Laboratories, France, using API 20E (BioMérieux^®) and MALDI-TOF Mass Spectrometry. Virulence factors, namely adhesins, were assessed with the slide agglutination method, and antimicrobial susceptibility testing was conducted across various antimicrobial classes. Out of 2367 E. coli strains isolated from cases of NCD, a high percentage were resistant to aminopenicillins (88.8%), aminoglycosides (89.1%), tetracyclines (79.7%), quinolones (48.4%), and sulphonamides (42.4%). More than half (58.6%) carried VFs, and 84.9% exhibited MDR profile, of which 61.34% (1233/2010) also harboured VFs. The adhesin CS31A-producing E. coli was the most prevalent, followed by the fimbrial adhesins F5 and F17 (60.8%, 20.0%, and 8.3%, respectively), all of which were associated with a high prevalence of MDR strains (79.1–93.9%). The highest occurrence of MDR profiles was observed in E. coli strains carrying CS31A and in those lacking VFs, both groups showing co-resistance to aminopenicillins, aminoglycosides, and tetracyclines or sulphonamides. The calf production sector may act as a reservoir for MDR E. coli strains, regardless of the presence of VFs, posing a major threat to public health and safety. Full article

Avian colibacillosis caused by avian pathogenic Escherichia coli (APEC) strains is a bacterial disease responsible for enormous economic losses in the poultry industry, due to high mortality rates in farms, antibiotic therapy costs, and seizures at slaughterhouses. The aim of this study was to characterize the serogroups and molecular features of extended spectrum β-lactamase (ESBL)-producing APEC isolates recovered from 248 liver samples of 215 broilers and 33 turkeys with colibacillosis lesions in northeast Algeria. For this, microbiological tests were carried out, according to the recommended standards: E. coli isolates were recovered using standard microbiological protocols, and identification was carried out by MALDI-TOF MS. Serogrouping was performed using a rapid agglutination slide and the antisera of three O somatic groups (O1, O2, O78). Antimicrobial susceptibility was determined by the disk diffusion method. PCR assays and sequencing were used to detect antimicrobial resistance genes, integrons, phylogrouping, and MLST. Conjugation experiments were also conducted to determine the transferability of the retrieved ESBL-encoding genes. Overall, 211 (85.1%) APEC isolates were collected (one per positive sample), and 164 (77.7%) of them were typable. The O2 and O1 serogroups were the most detected (46.1% in broiler typable isolates and 61.5% in turkey typable isolates). Seventeen APEC isolates were ESBL-producers and harbored the following genes (number of isolates): bla_CTX-M-1 (14), bla_CTX-M-15 (2), and bla_SHV-12 (1). They belonged to phylogroups D (10 isolates), B1 (6 isolates), and B2 (1 isolate). The MLST of 13 ESBL producers revealed seven STs: ST23, ST38, ST48, ST117, ST131, ST1146, and ST5087. The ESBL-encoding genes were transferred by conjugation among 15 ESBL-producing isolates, and transconjugants acquired either the IncK or IncI1 plasmids. Concerted efforts from all poultry actors are needed to establish surveillance monitoring strategies to mitigate the spread of ESBL-producing isolates implicated in avian colibacillosis. Full article

The rising prevalence of pathogenic bacteria in livestock meat poses a growing public health concern in China. The determination of antimicrobial resistance (AMR) is critical for the clinical management of foodborne infections stemming from livestock meat consumption. This study aimed to assess the prevalence of pathogenic bacteria in livestock meat (pork, beef, and mutton) sampled in China in 2021 and to identify the most common AMR patterns among the isolated pathogens. A total of 2515 raw livestock meat samples were collected across 15 provinces in China during 2021. Pathogen detection, including Listeria monocytogenes, Salmonella, and diarrheagenic Escherichia coli (DEC), followed China’s national food safety standards. All Salmonella isolates underwent serotyping via slide agglutination. Antimicrobial susceptibility of Salmonella and DEC isolates was assessed using the broth dilution method. The detection rates for L. monocytogenes, Salmonella, and DEC in raw livestock meat were 9.06% (228/2, 515), 10.54% (265/2, 515), and 6.16% (155/2, 515), respectively. Pork showed the highest contamination rates for Salmonella and DEC, with prevalence rates of 17.60% (214/1, 216, χ2 = 124.62, p < 0.05) and 7.89% (96/1, 216, χ2 = 14.466, p < 0.05), respectively. L. monocytogenes contamination was notably higher in chilled (14.43%, 84/582) and frozen (12.39%, 55/444) meat than in fresh meat (χ2 = 43.510, p < 0.05). In contrast, Salmonella (12.09%, 180/1489, χ2 = 15.173, p < 0.05) and DEC (7.25%, 108/1489, χ2 = 12.275, p < 0.05) were more prevalent in fresh meat than in chilled or frozen samples. The predominant Salmonella serotypes identified were Salmonella enterica subsp. enterica serovar Typhimurium, followed by Salmonella enterica serovar Derby, Salmonella enterica serovar Rissen, Salmonella enterica serovar London, and Salmonella enterica serotype Enteritidis. Enteroaggregative E. coli was the most frequent pathotype among DEC (84.7%, 133/157), followed by enteropathogenic E. coli (8.3%, 13/157) and enterohemorrhagic E. coli (5.1%, 8/157). Among the 14 tested antimicrobial agents, Salmonella isolates demonstrated an overall resistance rate of 87.50%, while DEC exhibited a resistance rate of 84.70%. Ampicillin and tetracycline showed the highest resistance rates in both pathogens. Multi-drug resistance (MDR) was observed in 67.53% of Salmonella isolates (183 isolates) and 57.96% of DEC isolates (91 isolates). This study highlights the significant contamination of retail raw livestock meat in China by L. monocytogenes, Salmonella, and DEC. The high resistance of MDR in both pathogens poses serious public health risks. Chinese food safety and veterinary authorities should implement stricter measures to control pathogen contamination and regulate the use of antimicrobials in livestock to mitigate these risks. Full article

The development of artificial stone from the agglutination of polymeric resin using industrial wastes can be a viable alternative from a technical, economic, and sustainable point of view. The main objective of the present work was to evaluate the physical, mechanical, and structural properties of artificial stones based on quartzite waste added into a synthetic, epoxy, or biodegradable polyurethane polymer matrix. Artificial stone plates were produced through the vacuum vibration and compression method, using 85 wt% of quartzite waste. The material was manufactured under the following conditions: 3 MPa compaction pressure and 90 and 80 °C curing temperature. The samples were characterized to evaluate physical and mechanical parameters and microstructure properties. As a result, the artificial stone plates developed obtained ≤0.16% water absorption, ≤0.38% porosity, and 26.96 and 10.7 MPa flexural strength (epoxy and polyurethane resin, respectively). A wear test established both artificial quartzite stone with epoxy resin (AS-EP) and vegetable polyurethane resin (AS-PU) high traffic materials. Hard body impact resistance classified AS-EP as a low height material and AS-PU as a very high height material. The petrographic slides analysis revealed that AS-EP has the best load distribution. We concluded the feasibility of manufacturing artificial stone, which would minimize the environmental impacts that would be caused by this waste disposal. We concluded that the production of artificial rock shows the potential and that it also helps to reduce environmental impacts. Full article

Misappropriation of public lands is an ongoing government concern. In Brazil, the beach zone is public property, but many private establishments use it for economic purposes, requiring constant inspection. Among the undue targets, the individual mapping of straw beach umbrellas (SBUs) attached to the sand is a great challenge due to their small size, high presence, and agglutinated appearance. This study aims to automatically detect and count SBUs on public beaches using high-resolution images and instance segmentation, obtaining pixel-wise semantic information and individual object detection. This study is the first instance segmentation application on coastal areas and the first using WorldView-3 (WV-3) images. We used the Mask-RCNN with some modifications: (a) multispectral input for the WorldView3 imagery (eight channels), (b) improved the sliding window algorithm for large image classification, and (c) comparison of different image resizing ratios to improve small object detection since the SBUs are small objects (<32² pixels) even using high-resolution images (31 cm). The accuracy analysis used standard COCO metrics considering the original image and three scale ratios (2×, 4×, and 8× resolution increase). The average precision (AP) results increased proportionally to the image resolution: 30.49% (original image), 48.24% (2×), 53.45% (4×), and 58.11% (8×). The 8× model presented 94% AP50, classifying nearly all SBUs correctly. Moreover, the improved sliding window approach enables the classification of large areas providing automatic counting and estimating the size of the objects, proving to be effective for inspecting large coastal areas and providing insightful information for public managers. This remote sensing application impacts the inspection cost, tribute, and environmental conditions. Full article

The present study was undertaken to investigate the presence of Salmonella spp. in the faeces of client-owned cats in urban areas and to evaluate the risk that is posed to public health. Fresh faecal samples were collected directly from the rectums from 53 diarrhoeic and 32 non-diarrhoeic cats. The samples were individually screened for the presence of Salmonella spp. using standard methods and, in the case of positive findings, the resulting typical colonies were then biochemically confirmed using the VITEK^®2 automated system. Subsequently, all of the Salmonella spp. isolates were molecularly tested for the presence of the invA gene. All of the isolates were serotyped using the slide agglutination technique according to the White–Kauffmann–Le Minor scheme. The phenotypic antimicrobial susceptibility profile of the isolated strains was obtained from the VITEK^®2 system using specific cards from the Gram-negative bacteria. A total of 16 of the samples (18.82%) tested positive for Salmonella spp. according to conventional and molecular testing methods. Serotyping of the Salmonella isolates showed the presence of three serotypes, namely S. enteritidis (n = 9; 56.3%), S. typhimurium (n = 4; 25%), and S. kentucky (n = 3; 18.8%). All of the tested strains showed strong resistance towards cefazolin, cefepime, ceftazidime, and ceftriaxone. Additionally, resistance (listed in descending order of strength) was observed to trimethoprim/sulfamethoxazole (11/16; 68.8%), ampicillin (10/16; 62.5%), ampicillin/sulbactam (9/16; 56.3%), gentamicin (9/16; 56.3%), nitrofurantoin (8/16; 50.0%), and amikacin (5/16; 31.3%). No resistance was expressed against ciprofloxacin, ertapenem, imipenem, levofloxacin, piperacillin/tazobactam, and tobramycin. The results of this study highlight a substantial public health issue and medical concern, especially in vulnerable people, such as children, the elderly, and immunocompromised individuals. Full article

The monophasic variant of Salmonella Typhimurium has emerged and increased rapidly worldwide during the past two decades. The loss of genes encoding the second-phase flagella and the acquirement of the multi-drug resistance cassette are the main genomic characteristics of the S. Typhimurium monophasic variant. In this study, two Salmonella strains were isolated from the knee effusion and feces of a 4-year-old girl who presented with a case of septic arthritis and fever, respectively. Primary serovar identification did not detect the second-phase flagellar antigens of the strains using the classical slide agglutination test. Whole-genome sequencing analysis was performed to reveal that the replacement of the fljAB operon by a 4.8-kb cassette from E. coli caused the non-expression of phase-2 flagellar antigens of the strains, which were confirmed to be a novel S. Virchow monophasic variant (Salmonella 6,7,14:r:-) by core-genome multi-locus sequence typing (cgMLST). Compared to the 16 published S. Virchow genomes, the two strains shared a unique CRISPR type of VCT12, and showed a close genetic relationship to S. Virchow BCW_2814 and BCW_2815 strains, isolated from Denmark and China, respectively, based on cgMLST and CRISPR typing. Additionally, the acquisition of Salmonella genomic island 2 (SGI2) with an antimicrobial resistance gene cassette enabled the strains to be multidrug-resistant to chloramphenicol, tetracycline, trimethoprim, and sulfamethoxazole. The emergence of the multidrug-resistant S. Virchow monophasic variant revealed that whole-genome sequencing and CRISPR typing could be applied to identify the serovaraints of Salmonella enterica strains in the national Salmonella surveillance system. Full article

Background: In Ghana, a blood group and rhesus type test is one of the essential recommended screening tests for women during antenatal care since blood transfusion is a key intervention for haemorrhage. We estimated the spatial accessibility to health facilities for blood group and type point-of-care (POC) testing in the Upper East Region (UER), Ghana. Methods: We assembled the attributes and spatial data of hospitals, clinics, and medical laboratories providing blood group and rhesus type POC testing in the UER. We also obtained the spatial data of all the 131 towns, and 94 health centres and community-based health planning and services (CHPS) compounds providing maternal healthcare in the region. We further obtained the topographical data of the region, and travel time estimated using an assumed tricycle speed of 20 km/h. We employed ArcGIS 10.5 to estimate the distance and travel time and locations with poor spatial access identified for priority improvement. Findings: In all, blood group and rhesus type POC testing was available in 18 health facilities comprising eight public hospitals and six health centres, one private hospital, and three medical laboratories used as referral points by neighbouring health centres and CHPS compounds without the service. Of the 94 health centres and CHPS compounds, 51.1% (48/94) and 66.4% (87/131) of the towns were within a 10 km range to a facility providing blood group and rhesus type testing service. The estimated mean distance to a health facility for blood group and rhesus POC testing was 8.9 ± 4.1 km, whilst the mean travel time was 17.8 ± 8.3 min. Builsa South district recorded the longest mean distance (25.6 ± 7.4 km), whilst Bongo district recorded the shortest (3.1 ± 1.9 km). The spatial autocorrelation results showed the health facilities providing blood group and rhesus type POC testing were randomly distributed in the region (Moran Index = 0.29; z-score = 1.37; p = 0.17). Conclusion: This study enabled the identification of district variations in spatial accessibility to blood group and rhesus type POC testing in the region for policy decisions. We urge the health authorities in Ghana to evaluate and implement recommended POC tests such as slide agglutination tests for blood group and rhesus type testing in resource-limited settings. Full article

The aim of this study was to investigate the occurrence, antibiotic susceptibility profiles, and virulence genes determinants of S. aureus isolated from milk obtained from retail outlets of the North-West Province, South Africa. To achieve this, 200 samples of raw, bulk and pasteurised milk were obtained randomly from supermarkets, shops and some farms in the North-West Province between May 2012 and April 2013. S. aureus was isolated and positively identified using morphological (Gram staining), biochemical (DNase, catalase, haemolysis and rapid slide agglutination) tests, protein profile analysis (MALDI-TOF mass spectrometry) and molecular (nuc specific PCR) methods. The antimicrobial resistance profiles of the isolates were determined using the phenotypic agar diffusion method. Genes encoding enterotoxins, exfoliative toxins and collagen adhesins were also screened using PCR. Among all the samples examined, 30 of 40 raw milk samples (75%), 25 of 85 bulk milk samples (29%) and 10 of 75 pasteurised milk samples (13%) were positive for S. aureus. One hundred and fifty-six PCR-confirmed S. aureus isolates were obtained from 75 contaminated milk samples. A large proportion (60%–100%) of the isolates was resistant to penicillin G, ampicillin, oxacillin, vancomycin, teicoplanin and erythromycin. On the contrary, low level resistance (8.3%–40%) was observed for gentamicin, kanamycin and sulphamethoxazole. Methicillin resistance was detected in 59% of the multidrug resistant isolates and this was a cause for concern. However, only a small proportion (20.6%) of these isolates possessed PBP2a which codes for Methicillin resistance in S. aureus. In addition, 32.7% of isolates possessed the sec gene whereas the sea, seb sed, see, cna, eta, etb genes were not detected. The findings of this study showed that raw, bulk and pasteurised milk in the North-West Province is contaminated with toxigenic and multi-drug resistant S. aureus strains. There is a need to implement appropriate control measures to reduce contamination as well as the spread of virulent S. aureus strains and the burden of disease in humans. Full article