Antimicrobial Resistance Index Research Articles

The prevalence, enterotoxigenic properties and antimicrobial susceptibility of Staphylococcus aureus isolated from various foods of animal origin

This study aimed to determine the prevalence, enterotoxigenic properties and antimicrobial resistance profile of Staphylococcus aureus isolated from 850 food samples, including bulk tank milk, Tulum cheese, chicken meat and beef carcasses, in Türkiye. S. aureus contamination rates and the mean contamination levels of 86 positive samples from bulk tank milk, Tulum cheese, chicken meat and beef carcasses were 10.8% (n:49) and 3.01±0.48 log cfu/ml, 17% (n:17) and 3.08±0.42 log cfu/g, 12% (n:12) and 2.89±0.27 log cfu/g, and 4% (n:8) and 1.28±0.54 log cfu/cm2 , respectively. 39 out of 86 isolates (45.3%) had one or more enterotoxin genes (sea-see, seg-selj, sep). sed was the most common classical enterotoxin gene, whereas sei was the most common new enterotoxin gene. Antimicrobial susceptibility testing against 16 antibiotics performed by VITEK 2 showed that 61 isolates (70.9%) were resistant to various antibiotics. 32.8% of the resistant isolates were multidrug resistant (MDR) and the mean multiple antimicrobial resistance (MAR) index was 0.301. The isolates were mostly resistant to penicillin (63.9%), followed by oxacillin (24.4%), clindamycin (19.7%) and erythromycin (12.7%). mecA was detected in 13 isolates (15.1%), but no mecC was found. It was concluded that most of the S. aureus isolates had enterotoxin genes which might cause foodborne intoxications. The high antibiotic resistance rates observed in these strains, including MRSA, may also result in some public health hazards.

THE CORRESPONDENCE OF THE CARBAPENEMASE GENOTYPE AND PHENOTYPIC ANTIMICROBIAL PROFILES OF PSEUDOMONAS AERUGINOSA

The aim of the study was to determine the correspondence between the carbapenemase genotype and the phenotypic antimicrobial profiles of P. aeruginosa. Materials and methods. The study included 51 clinical isolates of P. aeruginosa, isolated from the patients with post-operative complications of the respiratory organs. The final identification of the obtained isolates was performed in the Riesbeck laboratory using MALDI-ToF (Bruker), followed by the determination of their sensitivity to antimicrobial drugs at the EUCAST Development Laboratory (Växjö, Sweden). Determination of the resistance genes was carried out by using polymerase chain reaction in real time (PCR-RF). The antimicrobial resistance index (ARI) was determined according to the method of G.V. de Socio. Statistical analysis was performed using the standard IBM SPSS Statistics software version 22.0 and GraphPad Prism Software 10.1.0. (USA, 2023). Results. 39 strains of P. aeruginosa (76.5%) showed polyresistance, and 26 of them (51.0%) were resistant to all antibiotics. According to research data, P. aeruginosa isolates most often carried the blaVIM gene. Genetically determined production of oxacillinase group -lactamase class D among clinical isolates of P. aeruginosa occurred somewhat less often. Based on the obtained results, four carbapenemase genetic resistotypes of P. aeruginosa as pathogens of respiratory tract complications in critically ill patients were established. We detected the antimicrobial resistance index (ARI) based on the phenotypic characteristics of P. aeruginosa at the level of 0.690.39. The phenomenon of statistically reliable correlation of the ARI of microorganisms by phenotypic characteristics with their carbapenemase genetic resistotypes was established. Conclusions. 76.5% of strains of P. aeruginosa show polyresistance, and 51.0% of them are resistant to all antibiotics. Four different carbapenemase genetic resistotypes of P. aeruginosa as pathogens of respiratory tract complications in critically ill patients were established. There is the phenomenon of statistically reliable correlation of the ARI of microorganisms by phenotypic characteristics with their carbapenemase genetic resistotypes.

Oxidative stress, gene expression and histopathology of cultured gilthead sea bream (Sparus aurata) naturally co-infected with Ergasilus sieboldi and Vibrio alginolyticus

BackgroundParasitic and bacterial co-infections have been associated with increasing fish mortalities and severe economic losses in aquaculture through the past three decades. The aim of this study was to evaluate the oxidative stress, histopathology, and immune gene expression profile of gilthead sea bream (Sparus aurata) co-infected with Ergasilus sieboldi and Vibrio alginolyticus.ResultsVibrio alginolyticus and Ergasilus sieboldi were identified using 16 S rRNA and 28 S rRNA sequencing, respectively. The collagenase virulence gene was found in all Vibrio alginolyticus isolates, and the multiple antimicrobial resistance index ranged from 0.286 to 0.857. Oxidant-antioxidant parameters in the gills, skin, and muscles of naturally infected fish revealed increased lipid peroxidation levels and a decrease in catalase and glutathione antioxidant activities. Moreover, naturally co-infected gilthead sea bream exhibited substantial up-regulation of il-1β, tnf-α, and cyp1a1. Ergasilus sieboldi encircled gill lamellae with its second antennae, exhibited severe gill architectural deformation with extensive eosinophilic granular cell infiltration. Vibrio alginolyticus infection caused skin and muscle necrosis in gilthead sea bream.ConclusionThis study described some details about the gill, skin and muscle tissue defense mechanisms of gilthead sea bream against Ergasilus sieboldi and Vibrio alginolyticus co-infections. The prevalence of co-infections was 100%, and no resistant fish were detected. These co-infections imbalance the health status of the fish by hampering the oxidant-antioxidant mechanisms and proinflammatory/inflammatory immune genes to a more detrimental side. Our results suggest that simultaneous screening for bacterial and parasitic pathogens should be considered.

MOLECULAR IDENTIFICATION AND ANTIBIOGRAM OF METHICILLIN-RESISTANT STAPHYLOCOCCUS AUREUS FROM WOUNDS OF BOTH IN- AND OUT-PATIENTS AT UNIVERSITY OF BENIN TEACHING HOSPITAL (UBTH), BENIN CITY, NIGERIA

Methicillin-resistant Staphylococcus aureus (MRSA) stands as a prominent bacterial pathogen associated with various human infections, characterized by its remarkable ability to rapidly develop resistance to multiple antibiotics. The study aimed to characterize MRSA isolated from wounds among hospital patients. A total of eighty-seven unique S. aureus isolates were obtained from wound cultures collected from patients at the University of Benin Teaching Hospital (UBTH) in Benin City, Nigeria. These samples underwent assessment for methicillin resistance through conventional cultural methods, and detection of methicillin resistance (mecA) and S. aureus specific (nuc) genes using PCR amplification. The MRSA isolates underwent assessment for antimicrobial resistance through disc diffusion testing and for virulence factors using phenotypic testing procedures. An overall prevalence of 34/87 (39.1%) MRSA isolates was recorded. Based on the source of the isolate, the distribution of MRSA isolates from in-patients was 22/56 (39.3%) and out-patients was 12/31 (39.7%). Total Panton valentine leucocidin (PVL) screening revealed 11/34 (32.4%). All the isolates were resistant to penicillin 34/34 (100%) and cefepime 34/34 (100%). Lower level of resistance was demonstrated towards ciprofloxacin 3/34 (8.8%). Overall, every isolate displayed resistance to at least three antibiotics, resulting in a multiple antimicrobial resistance index of at least 0.33. The total virulence factors observed were beta-hemolytic activity 22/34 (64.7%), protease activity 14/34 (41.2%), and lipase activity 19/34 (55.9%). This study emphasized the significance of regularly monitoring MRSA prevalence within both the hospital and the local community. Therefore, the need for better intervention and continuous enlightenment on risks associated with the abuse...

Comparison of genotypic and phenotypic antimicrobial profile in carbapenemases producing Klebsiella pneumoniae.

Prompt administration of appropriate antibiotic therapy is crucial in improving outcomes, particularly in cases sustained by multi-drug resistant strains. Although phenotypic antimicrobial susceptibility testing (AST) represents the gold standard to address antibiotics treatment, the long time required to obtained affordable results could negatively affect the prognosis. In contrast, rapid genotypic AST provide essential information for treatment and surveillance program. In order to evaluate the potential adoption of rapid AST in clinical routine, we compared the genotypic and phenotypic antimicrobial profiles of different K.pneumoniae strains, characterized by different expression of carbapenemases-encoding genes. A set of 109 strains of Cr-Kp were tested for the antimicrobial drugs by the automatized Vitek II system and, in parallel, to the new combination of β-lactams/β-lactamases inhibitors (BL/BLI) by Etest. An antimicrobial resistance index (ARI) was calculated for each strain, assigning each 1 or 0 points based on observed resistance/susceptibility, and dividing the total by the number of antibiotics tested. Kruskal-Wallis test, followed by Dunn's post hoc test (Bonferroni correction), were used to compare quantitative variables among resistance gene subgroups. We observed a higher ARI score in KPC/OXA-48 strains, similar profile in KPC alone and KPC/CTX-M groups and a significant lower resistance in no-carbapenemases-producing group. Same trend was observed in AST for BL/BLI. These preliminary results showed a close link between genotypic and phenotypic AST, supporting the adoption of rapid AST in cases of severe infections, ensuring to saving time and providing, the surveillance of MDR strains and improving stewardship programs.

The Antimicrobial Resistance Index and Fournier Gangrene Severity Index of Patients Diagnosed with Fournier's Gangrene in a Tertiary Hospital in North Eastern Romania.

Background: Although rare, Fournier's gangrene is a major urological emergency. We aimed to learn more about the pathogenesis of Fournier's gangrene and assess the antibiotic resistance patterns in individuals with this disease. Methods: We retrospectively evaluated the patients diagnosed with and treated for Fournier's gangrene in a Neamt county hospital and "CI Parhon" Clinical Hospital in Iasi, Romania between 1 January 2016 and 1 June 2022. Results: We included a total of 40 patients, all males; of these, 12.5% died. In our study, in the patients that died, the adverse prognostic factors were a higher body temperature (38.12 ± 0.68 vs. 38.94 ± 0.85 °C; p = 0.009), an elevated WBC (17.4 ± 5.46 vs. 25.23 ± 7.48; p = 0.003), obesity (14.28% vs. 60%; p = 0.04), and a significantly higher FGSI (4.17 ± 2.80 vs. 9.4 ± 3.2; p = 0.0002) as well as MAR index (0.37 ± 0.29 vs. 0.59 ± 0.24; p = 0.036). These patients were more likely to have liver affections than those in the group who survived, but the difference was not significant. The most frequently identified microorganism in the tissue secretions culture was E. coli (40%), followed by Klebsiella pneumoniae (30%) and Enterococcus (10%). The highest MAR index was encountered in Acinetobacter (1), in a patient that did not survive, followed by Pseudomonas (0.85) and Proteus (0.75). Conclusions: Fournier's gangrene remains a fatal condition, a highly resistant causative microorganism that is not always correlated with a poor prognosis.

In Vivo Effect of a Nisin–Biogel on the Antimicrobial and Virulence Signatures of Canine Oral Enterococci

Periodontal disease is a relevant oral disease in dogs and nisin-biogel has been previously proposed to be used in its control. Enterococci, as inhabitants of the oral cavity with a high genetic versatility, are a reliable bacterial model for antimicrobial studies. Our goal was to evaluate the in vivo influence of the long-term dental application of the nisin-biogel on the virulence and antimicrobial signatures of canine oral enterococci. Twenty dogs were randomly allocated to one of two groups (treatment group-TG with nisin-biogel dental application, or control group-CG without treatment) and submitted to dental plaque sampling at day 0 and after 90 days (T90). Samples were processed for Enterococcus spp. isolation, quantification, identification, molecular typing and antimicrobial and virulence characterization. From a total of 140 enterococci, molecular typing allowed us to obtain 70 representative isolates, mostly identified as E. faecalis and E. faecium. No significant differences (p > 0.05) were observed in the virulence index of the isolates obtained from samples collected from the TG and CG at T90. At T90, a statistically significant difference (p = 0.0008) was observed in the antimicrobial resistance index between the isolates from the TC and CG. Oral enterococci were revealed to be reservoirs of high resistant and virulent phenotypes.

Prevalence of Antimicrobial Resistance and Respective Genes among Bacillus spp., a Versatile Bio-Fungicide.

The plant rhizosphere is not only a reservoir of microbes but also a hub of antimicrobial resistance genes. Rhizospheric Bacillus spp. are the potential bio-inoculants with a versatile application in agriculture as bio-fertilizer and bio-fungicide. In the current study, the potential bio-control agent that is the Bacillus species (n = 7) was screened for the antimicrobial resistance pattern to assess their risk before registering them as a bio-inoculant. All of the Bacillus spp. were categorized as multi-drug-resistant (MDR), bacteria but none of them was either pan-drug-resistant (PDR) or extensive-drug-resistant (XDR). The multiple antimicrobial resistance (MAR) index of Bacillus spp. was higher than the critical value (0.2). The Bacillus spp. showed resistance to antimicrobial classes such as β lactam, macrolides, sulfonamides, tetracycline, aminoglycosides, and lincosamide. Various antimicrobial resistance genes, namely VmiR, ImrB, tetL, mphK, ant-6, penp, and bla OXA, associated with different mechanisms of resistance, were also detected in Bacillus spp. The Bacillus spp. also showed stress-tolerance traits such as ACC deaminase and EPS activity except the strains MAZ-117 and FZV-34, respectively. A significant correlation was observed between the PGPR and antimicrobial resistance, which shows that they may have adapted drug-resistance mechanisms to tolerate the environmental stress. These findings suggest that bio-fungicidal Bacillus spp. could be used very carefully on a commercial scale.

Molecular Characterization and the Antimicrobial Resistance Profile of Salmonella spp. Isolated from Ready-to-Eat Foods in Ouagadougou, Burkina Faso.

The emergence of antimicrobial-resistantfood-borne bacteria is a great challenge to public health. This study was conducted to characterize and determine the resistance profile of Salmonella strains isolated from foods including sesames, ready-to-eat (RTE) salads, mango juices, and lettuce in Burkina Faso. One hundred and forty-eight biochemically identified Salmonella isolates were characterized by molecular amplification of Salmonella marker invA and spiC, misL, orfL, and pipD virulence genes. After that, all confirmed strains were examined for susceptibility to sixteen antimicrobials, and PCR amplifications were used to identify the following resistance genes: bla TEM, temA, temB, StrA, aadA, sul1, sul2, tet(A), and tet(B). One hundred and eight isolates were genetically confirmed as Salmonella spp. Virulence genes were observed in 57.4%, 55.6%, 49.1%, and 38% isolates for pipD, SpiC, misL, and orfL, respectively. Isolates have shown moderate resistance to gentamycin (26.8%), ampicillin (22.2%), cefoxitin (19.4%), and nalidixic acid (18.5%). All isolates were sensitive to six antibiotics, including cefotaxime, ceftazidime, aztreonam, imipenem, meropenem, and ciprofloxacin. Among the 66 isolates resistant to at least one antibiotic, 11 (16.7%) were multidrug resistant. The Multiple Antimicrobial Resistance (MAR) index of Salmonella serovars ranged from 0.06 to 0.53. PCR detected 7 resistance genes (tet(A), tet(B), bla TEM, temB, sul1, sul2, and aadA) in drug-resistant isolates. These findings raise serious concerns because ready-to-eat food in Burkina Faso could serve as a reservoir for spreading antimicrobial resistance genes worldwide.

Phenotypic and genotypic characterization of multi-drug resistant, biofilm forming, human invasive strain of Salmonella Typhimurium SMC25 isolated from poultry meat in India

Emergence of highly virulent and multi-drug resistant (MDR) strains of Salmonella in food products significantly impacts public health and demands continuous monitoring for their presence in the food chain. The ability of Salmonella to form biofilms under harsh environmental conditions accompanied by MDR serotypes underscores an important food safety threat. This study aimed to isolate, identify and characterize MDR, biofilm-forming Salmonella from local Indian dairy and meat products (n = 60). All of the 24 isolates of Salmonella produced biofilm and were categorized as strong (16.6%), moderate (58.3%), and weak (25%) biofilm producers. Multiple antimicrobial resistance (MAR) index of all the Salmonella isolates was ≥0.2. The strongest biofilm forming poultry meat isolate, Salmonella SMC25 demonstrated intermediate to complete resistance to 14 of 22 different antibiotics tested. Epifluorescence microscopy showed that biofilm formation initiated as early as 4 h, reaching zenith within 96 h and much denser and robust biofilm is formed on rough stainless steel (SS316) surface compared to smooth glass surface. The results corroborated with increased temporal production of exopolysaccharides (EPS), high cell surface hydrophobicity and upregulation of marker genes vital to biofilm-formation in Salmonella. Significantly, SMC25 was found to adhere and invade mammalian cell lines Caco2 and HepG2, thus posing a serious food safety threat. This study is important in comprehending the prevalence of multidrug resistant, biofilm-forming, invasive strains of foodborne Salmonella in Indian food products and is important for effective risk assessment besides ensuring better food safety and public health.

ISOLATION, CHARACTERIZATION AND ANTIBIOTIC SUSCEPTIBILITY PATTERN OF DIARRHEAGENIC ESCHERICHIA COLI (DEC) AMONG CHILDREN ATTENDING SOME SELECTED HOSPITALS WITHIN KADUNA METROPOLIS

Diarrhoea has been associated with significant morbidity and mortality, ranked the second cause of death in children aged 0 to 5 years. Bacteria, viruses, protozoa, and helminths have all been implicated in diarrhoea, however rotavirus and diarrhoeagenic E. coli (DEC) are the most common cause. This study aimed to determine the antibiotic susceptibility pattern of diarrheagenic Escherichia coli isolated from children 0-5 years attending selected hospitals in Kaduna metropolis. A total of 264 stool samples were collected from children attending four selected hospitals in Kaduna metropolis. Standard culture procedures and molecular techniques such as PCR and 16s rRNA were employed in isolation and characterization of diarrhoeagenic E. coli from the stool samples. The study established a prevalence of 24.2% for diarrheagenic Escherichia coli, and all the isolates demonstrated multiple antimicrobial resistance index (MARI) of 0.5 and above, and showed significant resistance against augmentin (100%), amoxacillin (100%), ampicillin-cloxacillin (ampiclox) (100%), erythromycin (100%), gentamycin (100%), cefoxitin (100%), cefuroxime (95%), ceftriazone (95%) and ceftaxidime (85%). The least (60%) resistance was observed against imipenem. The study concluded that antibiotics have not been very effective in the treatment of E. coli-related diarrhoea. The study, therefore, recommends the implementation of programmes geared towards good hygiene, good nutrition and good health

The Bacterial Profile and Antimicrobial Susceptibility Patterns of Urinary Tract Infection Patients at Pawe General Hospital, Northwest Ethiopia.

Urinary tract infection remains the most common infection widespread worldwide in both community and hospital settings. Rapidly increasing antibiotic resistance of uropathogens is resulting in limited treatment options. Thus, understanding the current uropathogens and their antimicrobial susceptibilities is essential for effective urinary tract infection treatment. The purpose of this study was to isolate, characterize, and determine the antimicrobial susceptibility patterns of bacterial pathogens associated with urinary tract infection at Pawe General Hospital in Northwest Ethiopia. A hospital-based cross-sectional study design was conducted from January to April, 2020, at Pawe General Hospital. Midstream urine specimens were collected from 141 individuals with suspected urinary tract infection for bacteriological identification and antimicrobial susceptibility testing. Among the 141 study participants, twenty-nine (20.6%) showed significant bacteriuria. Escherichia coli (42.6%) had the highest proportion of isolated uropathogen followed by Klebsiella spp. and Pseudomonas spp. each (10.7%); Proteus spp. (9.3%); coagulase negative staphylococci, Staphylococcus aureus, and Enterobacter spp. each (6.7%); Citrobacter spp. (4%); and Enterococcus faecalis and Streptococcus spp. each (1.3%). Outpatient isolates showed a resistance of 64% and 78.6% to amoxicillin-clavulanic acid and tetracycline, respectively. Inpatients showed 63.9% and 87.2% of resistance to cephalexin and tetracycline. It was also observed that all the isolates have a multiple antimicrobial resistance index greater than 0.20 except Citrobacter spp. (0.142) in inpatients. Even though in this locality, most isolates were sensitive to ceftriaxone, gentamicin, ciprofloxacin, nitrofurantoin, and norfloxacin, they are considered appropriate antimicrobials for empirical treatment of urinary tract bacterial infections. Periodic monitoring of etiology and drug susceptibility is highly recommended, along with health education on the transmission and causes of urinary tract infection.

Antimicrobial susceptibility in E. coli and Pasteurellaceae at the beginning and at the end of the fattening process in veal calves: Comparing ‘outdoor veal calf’ and conventional operations

Animal husbandry requires practical measures to limit antimicrobial resistance (AMR). Therefore, a novel management and housing concept for veal calf fattening was implemented on 19 intervention farms (IF) and evaluated regarding its effects on AMR in Escherichia (E.) coli, Pasteurella (P.) multocida and Mannheimia (M.) haemolytica in comparison with 19 conventional control farms (CF). Treatment intensity (−80%) and mortality (−50%) were significantly lower in IF than in CF, however, production parameters did not differ significantly between groups. Rectal and nasopharyngeal swabs were taken at the beginning and the end of the fattening period. Susceptibility testing by determination of the minimum inhibitory concentration was performed on 5420 isolates. The presence of AMR was described as prevalence of resistant isolates (%), by calculating the Antimicrobial Resistance Index (ARI: number of resistance of one isolate to single drugs/total number of drugs tested), by the occurrence of pansusceptible isolates (susceptible to all tested drugs, ARI=0), and by calculating the prevalence of multidrug (≥3) resistant isolates (MDR). Before slaughter, odds for carrying pansusceptible E. coli were higher in IF than in CF (+65%, p=0.022), whereas ARI was lower (−16%, p=0.003), and MDR isolates were less prevalent (−65%, p=0.001). For P. multocida, odds for carrying pansusceptible isolates were higher in IF before slaughter compared to CF (+990%, p=0.009). No differences between IF and CF were seen regarding the prevalence of pansuceptible M. haemolytica. These findings indicate that easy-to-implement measures to improve calf management can lead to a limitation of AMR in Swiss veal fattening farms.

Bovine mastitis in northeastern Brazil: Occurrence of emergent bacteria and their phenotypic and genotypic profile of antimicrobial resistance

The aim of this study was to identify emergent pathogens associated with bovine mastitis in northeastern Brazil and to characterize them for phenotypic and genotypic resistance to antimicrobials. A total of 321 milk samples from cows with subclinical mastitis were collected, and the isolates obtained in culture were identified using matrix-associated laser desorption-ionization - time of flight mass spectrometry. Phenotypic and genotypic antimicrobial resistance tests were performed. We identified 72 bacteria considered emergent in the study region: Enterococcus faecalis (26.3%; 19/72), Streptococcus agalactiae (22.2%; 16/72), Enterococcus faecium (20.0%; 15/72), Escherichia coli (6.9%; 5/72), 6.9% (5/72) Lactococcus garvieae (6.9%; 5/72), Acinetobacter baumannii (5.5%; 4/72), Bacillus subtilis (1.3%; 1/72), Kocuria marina (1.3%; 1/72), Macrococcus caseolyticus (1.3%; 1/72), Microbacterium resistens (1.3%; 1/72), Micrococcus luteus (1.3%; 1/72), Streptococcus dysgalactiae (1.3%; 1/72), Streptococcus hyovaginalis (1.3%; 1/72) and Streptococcus pluranimalium (1.3%; 1/72). The antibiogram revealed the following resistance profiles: ampicillin (77.7%; 56/72), cefoxitin (69.4%; 50/72), erythromycin (61.1%; 44/72), oxacillin (63.8%; 46/72), penicillin (79.1%; 57/72), tetracycline (63.8%; 46/72), gentamicin (25.0%; 18/72), and vancomycin (20.8%; 15/72). Of the isolates, 83.4% (60/72) showed multiple resistance to antimicrobials. The tetM gene was identified in 43.0% (31/72) of the isolates, followed by tetL (31.9%; 23/72), and blaZ (26.3%; 19/72). 83.4% (60/72) of the isolates presented a multiple antimicrobial resistance index higher than 0,2. Emergent bacteria with zoonotic and multiresistant potential occur in cows with mastitis in northeastern Brazil. It is necessary to monitor the occurrence of these and other bacteria in livestock environments and develop control strategies to prevent their spread.

High Levels of Multi Drug Resistant Escherichia coli Pathovars in Preharvest Environmental Samples: A Ticking Time Bomb for Fresh Produce Related Disease Outbreak

The preharvest environment provides a suitable platform for the emergence and dissemination of multidrug resistant pathogenic bacteria. This could be detrimental to public health and may lead to fresh produce related disease outbreaks when transferred to the food web. This study evaluated the occurrence and antibiogram fingerprints of the pathogenic strains of Escherichia coli (E. coli) recovered from irrigation water and agricultural soil samples in fresh produce farms in the Eastern Cape Province, South Africa. E. coli was isolated, pathotyped and screened for antibiogram fingerprints using standard cultural and molecular methods. An antibiogram-based K-means cluster analysis and neighbour-joining dendrogram was used to elucidate the relatedness of the isolates. Of the confirmed isolates, 37% harboured at least one of the screened virulence genes (VGs) that encode for intestinal and extraintestinal E. coli pathovars. The most prevalent pathovar/associated VG in all the samples was Enterohemorrhagic E. coli/stx2. Of all the antimicrobials tested, E. coli pathovars conferred the highest resistance against ampicillin with a median single antimicrobial resistance (AMR) index of 0.23 (IQR: 0.10–0.38, 95% CI: 0.16–0.27) for pathovars from irrigation water and 0.01 (IQR: 0.01–0.03, 95% CI: 0.01–0.03) for pathovars from agricultural soil. About 60 and 20% of the pathovars from irrigation water and agricultural soil were multi drug resistant with a median multiple AMR index of 0.41 (IQR: 0.25–0.52, 95% CI: 0.31–0.47) and 0.38 (IQR: 0.23–0.66, 95% CI: 0.19–0.69) respectively. The most prevalent resistance genes detected were sulI, catII, tetA and AmpC across all sample types. The blaTEM was the most prevalent extended-spectrum β-lactamase resistance gene detected. A positive correlation between the phenotypic and genotypic AMR profiles of the pathovars in irrigation water samples, r = 0.6, p ≤ 0.01 and agricultural soil samples, r = 0.8, p ≤ 0.01 was recorded. The antibiogram based dendrogram generated 11 and 7 clades from irrigation water and agricultural soil samples respectively, indicating that the isolates are highly diversified. The findings revealed the occurrence of highly diversified multidrug resistant E. coli pathovars in the preharvest environment, indicating potential public health threats.

Changes in resistance pattern of ESKAPE pathogens between 2010 and 2020 in the clinical center of University of Szeged, Hungary.

The acronym ESKAPE stands for six antibiotic-resistant bacterial pathogens namely, Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp. Monitoring their resistance is an important task for clinical microbiology laboratories. Our aim was to analyze the resistance patterns of these bacteria over ten years in clinical samples of our department. We examined the sample types from which these pathogens were most frequently isolated. The incidence of tests with resistant results for each pathogen in aggregate and the most important subgroups of each was also analyzed. We have also intended to predict the local priorities amongst these pathogens. The results of 1,268,126 antibiotic susceptibility tests performed on a total of 70,099 isolates over this period were examined. Most strains were derived from urine, blood culture, trachea, vagina, wounds, and abscesses. Prevalence of ESKAPE bacteria increased between 2011 and 2020 however, the steepest intensifications were seen in the cases of K. pneumoniae and P. aeruginosa. The number of antibiotic susceptibility tests with resistant results has also increased over the decade but the most notable increase was detected in E. faecium and A. baumannii. Based on the calculation of antimicrobial resistance index for each pathogen, the most serious challenges for us at present are A. baumannii, P. aeruginosa, and E. faecium and their multi-resistant forms. The theoretical prediction of proportion of resistant tests between 2020 and 2030 in our care area draws attention to a worrying trend in the cases of vancomycin-resistant E. faecium and carbapenem-resistant A. baumannii strains.

Non-diarrhoeic pigs as source of highly virulent and multidrug-resistant non-typhoidal Salmonella.

Food-producing animals act as reservoirs of non-typhoidal Salmonella (NTS) serovars with potential food safety and public health implications. The present cross-sectional study aimed at determining the prevalence of Salmonella serotypes in non-diarrhoeic pigs and characterizing the isolates using molecular tools. Salmonella isolates (n = 22) recovered from faecal samples of 194 randomly selected pigs were characterized for virulence and antimicrobial resistance and subtyped using XbaI-PFGE. The prevalence of Salmonella in apparently healthy non-diarrhoeic pigs was 11.3% (95%CI, 4.3-19.5%), with S. Weltevreden (81.8%) and S. Enteritidis (18.2%) being the serotypes detected. Salmonella isolates harboured virulence genes such as invA (100%), stn (100%), spvR/spvC (86.3%) and fimA (22.7%). Phenotypically, isolates showed sensitivity to chloramphenicol, levofloxacin and ciprofloxacin and resistance to tetracycline and ampicillin (100%), streptomycin (86.4%), amoxicillin-clavulanate (63.6%), cefotaxime (22.7%) and ceftriaxone (9.1%). Notably, 18.2% isolates were multidrug-resistant (≥ 3 antimicrobial class) with multiple antimicrobial resistance (MAR) index of 0.56-0.67 (18.2%), 0.44 (45.5%), 0.33 (31.8%) and 0.22 (4.5%). Genotypically, isolates carried various antibiotic resistance genes: ESBL (blaTEM and blaOXA), aminoglycoside (strA, strB and aadA1), sulphonamide (sul1, sul2 and dfrA1), tetracycline (tetA and tetB) and plasmid AmpC beta-lactamase (ACC, FOX, MOX, DHA, CIT and EBC). The present investigation emphasizes the epidemiological significance of PFGE typing in the detection of emerging strains of highly virulent and multidrug-resistant S. Weltevreden and S. Enteritidis in non-diarrhoeic pigs that pose serious public health implications in the pork supply chain environment. More extensive longitudinal study is warranted to provide epidemiological links between environmental reservoirs and animal and human infections in piggery settings.

High burden of multidrug resistant bacteria detected in Little Akaki River

Spread of antimicrobial-resistant bacteria between humans and animals occurs when the environment is contaminated with animal and human wastes. A total of 30 samples were collected from the Akaki river to identify antimicrobial-resistant bacteria. Bacterial enumeration and characterization was done by spreading serially diluted water samples on MacConkey agar. Sixty four bacterial isolates were identified and susceptibility tested using VITEK 2. The most frequently identified bacteria were Providencia alcalifaciens 10 (15.6%), Kluyvera cryocrescens 9 (14.1%) and Citrobacter freundii 7(10.9%), respectively. Multiple drug resistant bacteria were identified, constituting 17 (28%) of the 64 identified isolates. Multiple antimicrobial resistance (MAR) index of the six sites laid in the range 0.13–0.27, being the highest score located downstream of all the sampling sites. Species MAR index varied from 0.12 to 0.40. Out of 64 isolates, 54 (84.4%) of them were resistant to Ampicillin. On the contrary, most of the isolates were sensitive to Amikacin and meropenem. In conclusion, our findings indicated E.coli count was above the WHO permissible levels. The predominant isolates were P. alcalifaciens, and C. freundii. The MAR index of major isolates was greater than two, implying the study sites were exposed to high-risk sources of human or animal contamination.

Occurrence of Virulence and Antimicrobial Resistance Determinants in Vibrio harveyi Isolated from Marine Food Fish Cultured in Korea.

Vibrio harveyi is a significant cause of infection in both marine animals and humans. It has been reported frequently in seafood-borne infections worldwide. This study was conducted to determine the potential health impact of the V. harveyi isolated from marine food fish cultured in Korea concerning their virulence and antimicrobial resistance. A total of 49 V. harveyi samples were isolated by biochemical tests and multiplex PCR. Phenotypic detection of virulence factors resulted DNase activity (81.63%), hemolysis (α = 75.51% and β = 12.25), gelatinase activity (71.43%), protease production (71.43%), phospholipase activity (65.31%), and lipase production (34.69%). Virulence genes, including VPI, tlh, tdh, toxR, VAC, and ctxAB, were detected in 57.14%, 44.90%, 36.73%, 22.45%, 12.24%, and 8.16% of the isolates, respectively. Resistance to ampicillin (77.55%), oxacillin (69.39%), nalidixic acid (53.06%), amoxicillin (46.94%), oxytetracycline (46.94%), colistin sulfate (34.69%), fosfomycin (34.69%), chloramphenicol (32.65%), streptomycin (32.65%), cephalothin (28.57%), oxytetracycline (26.53%), ceftriaxone (20.41%), erythromycin (14.29%), and cefoxitin (12.24%) was detected in disc diffusion assay. Most of the isolates were classified as multidrug resistant as they scored multiple antimicrobial resistance index ≥0.2. Furthermore, antimicrobial resistance genes tetB, qnrA, intI1 (Class 1 integron integrase), aac(6')-Ib, blaSHV, blaCTX-M, strA-strB, tetA, aphAI-IAB, qnrC, qnrS, and blaTEM were found in 81.63%, 67.35%, 61.22%, 46.94%, 44.90%, 44.90%, 36.73%, 18.37%, 10.20%, 10.20%, 8.16% and 6.12% of the isolates, respectively. In conclusion, the development of antimicrobial resistance among V. harveyi will ultimately reduce the efficacy of antimicrobials used for treating and can favor the development of more virulent V. harveyi strains.

Antimicrobial-resistant in Escherichia coli isolated from different effluent locations within Ahmadu Bello University, Zaria, Nigeria

The safety of municipal water is increasingly becoming of concern globally. Agricultural activities, industrial and residential effluents and community waste are ways through which water sources are contaminated and resistant bacteria can be spread via effluents to municipal water. The study aimed to isolate and determine the distribution of antimicrobial drug-resistant Escherichia coli from different points of the University sewer system in April 2018. A total of 48 samples were collected twice weekly from the six randomly selected inspection chamber sites out of the 14 identified sites. The selected sites of the sewer were located in some hostels, markets and health service areas within the ABU. main campus. The samples were processed by culturing on an EMB agar plate followed by biochemical characterization using conventional biochemical tests and Microbact 12E. An antimicrobial sensitivity test was also carried out using 13 different antibiotic discs. The results obtained revealed that the Community market had an isolation rate of 4(50%), while Sickbay had 3(37.5%) and Danfodiyo hostel with 2(25%). Multiple antimicrobial resistance index (MARI) was found to be 0.31 from four isolates (36%) of E. coli of which 3(75%) were sampled from Sickbay and 1(25%) from ABU Dam. Also, five isolates (45%) had MARI of 0.23, of which 2(40%) were sampled from Danfodiyo hostel, 1(20%) from Ribadu hostel and 2(40%) from Community market. The E. coli isolates were more resistant to Ampicillin, tetracycline and cephalothin. Other bacteria isolated were Klebsiella ozaenae, Hapnea alvei and Morganella morganii all with MARI of 0.31. There is a need for public health awareness on the effect of discharging antibiotic-resistant E. coli contaminated effluent into the environment and water bodies. Hence, the public health significance of recycling such water for domestic usage and agricultural purpose.