Molecular Epidemiology of Salmonella enterica in Poultry in South Africa Using the Farm-to-Fork Approach

The presence of the zoonotic pathogen Salmonella in the food supply chain poses a serious public health threat. This study describes the prevalence, susceptibility profiles, virulence patterns, and clonality of Salmonella from a poultry flock monitored over six weeks, using the farm-to-fork approach. Salmonella was isolated using selective media and confirmed to the genus and species level by real-time polymerase chain reaction (RT-PCR) of the invA and iroB genes, respectively. Antimicrobial susceptibility profiles were determined using Vitek-2 and the Kirby–Bauer disk diffusion method against a panel of 21 antibiotics recommended by the World Health Organisation Advisory Group on Integrated Surveillance of Antimicrobial Resistance (WHO-AGISAR). Selected virulence genes were identified by conventional PCR, and clonality was determined using enterobacterial repetitive intergenic consensus PCR (ERIC-PCR). Salmonella was present in 32.1% of the samples: on the farm (30.9%), at the abattoir (0.6%), and during house decontamination (0.6%). A total of 210 isolates contained the invA and iroB genes. Litter, faeces, and carcass rinsate isolates were classified as resistant to cefuroxime (45.2%), cefoxitin (1.9%), chloramphenicol (1.9%), nitrofurantoin (0.4%), pefloxacin (11.4%), and azithromycin (11%). Multidrug resistance (MDR) was observed among 3.8% of the isolates. All wastewater and 72.4% of carcass rinsate isolates were fully susceptible. All isolates harboured the misL, orfL, pipD, stn, spiC, hilA, and sopB virulence genes, while pefA, spvA, spvB, and spvC were absent. In addition, fliC was only present among the wastewater isolates. Various ERIC-PCR patterns were observed throughout the continuum with different subtypes, indicating the unrelated spread of Salmonella. This study concluded that poultry and the poultry environment serve as reservoirs for resistant and pathogenic Salmonella. However, there was no evidence of transmission along the farm-to-fork continuum.

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Virulence-Associated Genes and Antimicrobial Resistance of Aeromonas hydrophila Isolates from Animal, Food, and Human Sources in Brazil

BioMed Research International ◽

10.1155/2020/1052607 ◽

2020 ◽

Vol 2020 ◽

pp. 1-8

Author(s):

Emily Moraes Roges ◽

Verônica Dias Gonçalves ◽

Maira Duarte Cardoso ◽

Marcia Lima Festivo ◽

Salvatore Siciliano ◽

...

Keyword(s):

Antimicrobial Resistance ◽

Aeromonas Hydrophila ◽

Pathogenic Bacteria ◽

Virulence Genes ◽

Animal Health ◽

Diffusion Method ◽

Aquatic Environments ◽

Disk Diffusion Method ◽

Polymerase Chain ◽

Human Source

Aeromonads are natural inhabitants of aquatic environments and may be associated with various human or animal diseases. Its pathogenicity is complex and multifactorial and is associated with many virulence factors. In this study, 110 selected Aeromonas hydrophila isolates isolated from food, animals, and human clinical material from 2010 to 2015 were analyzed. Antimicrobial susceptibility testing was performed by the disk diffusion method, and polymerase chain reaction was conducted to investigate the virulence genes hemolysin (hlyA), cytotoxic enterotoxin (act), heat-labile cytotonic enterotoxin (alt), aerolysin (aerA), and DNase-nuclease (exu). At least 92.7% of the isolates had one of the investigated virulence genes. Twenty different virulence profiles among the isolates were recognized, and the five investigated virulence genes were observed in four isolates. Human source isolates showed greater diversity than food and animal sources. Antimicrobial resistance was observed in 46.4% of the isolates, and multidrug resistance was detected in 3.6% of the isolates. Among the 120 isolates, 45% were resistant to cefoxitin; 23.5% to nalidixic acid; 16.6% to tetracycline; 13.7% to cefotaxime and imipenem; 11.8% to ceftazidime; 5.9% to amikacin, gentamicin, and sulfamethoxazole-trimethoprim; and 3.9% to ciprofloxacin and nitrofurantoin. Overall, the findings of our study indicated the presence of virulence genes and that antimicrobial resistance in A. hydrophila isolates in this study is compatible with potentially pathogenic bacteria. This information will allow us to recognize the potential risk through circulating isolates in animal health and public health and the spread through the food chain offering subsidies for appropriate sanitary actions.

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Virulence characterization of Klebsiella pneumoniae and its relation with ESBL and AmpC beta-lactamase associated resistance

Iranian Journal of Microbiology ◽

10.18502/ijm.v12i2.2613 ◽

2020 ◽

Author(s):

Elghar Soltani ◽

Alka Hasani ◽

Mohammad Ahangarzadeh Rezaee ◽

Tahereh Pirzadeh ◽

Mahin Ahangar Oskouee ◽

...

Keyword(s):

Antibiotic Resistance ◽

Klebsiella Pneumoniae ◽

Virulence Genes ◽

Diffusion Method ◽

Beta Lactamase ◽

Disk Diffusion Method ◽

Extended Spectrum Beta Lactamase ◽

Virulence Trait ◽

Polymerase Chain

Background and Objectives: Trend analysis reveals that Klebsiella pneumoniae has witnessed a steep enhancement in the antibiotic resistance and virulence over the last few decades. The present investigation aimed at a comprehensive approach investigating antibiotic susceptibility including, extended spectrum beta-lactamase (ESBL) and AmpC β-lactamase (AmpC) resistance and the prevalence of virulence genes among the K. pneumoniae isolates. Materials and Methods: Sixty-one K. pneumoniae isolates were obtained from various clinical infections. Antimicrobial susceptibility was performed by disk diffusion method. The Mast® D68C test detected the presence of ESBLs and AmpCs phenotypically, and later presence of ESBL and AmpC genes was observed by polymerase chain reaction (PCR). Multi- plex-PCR was performed to investigate various virulence genes. CMY-2 Results: Amongst 61 K. pneumoniae isolates, 59% were observed as ESBL and 14.7% as AmpC producers. All ESBL CTX-M-15 producers were positive for bla CTX-M-15 , while bla CTX-M-14 was observed in 54.1% isolates. The frequency of AmpC genes was CMY-2 as follows: bla CMY-2 (60.7%) and bla DHA-1 (34.4%). The most frequent virulence genes were those encoding enterobactin and DHA-1 lipopolysaccharide. Presence of mrkD was associated with bla CMY-2 DHA-1 gene, while bla significantly (p≤0.05) correlated DHA-1 with the presence of iutA and rmpA virulence genes. bla positive isolates had urine as a significant source, while bla positive isolates were mainly collected from wound exudates (p≤0.05). Conclusion: Our results highlight that ESBL and AmpC production along with a plethora of virulence trait on K. pneumoni- ae should be adequately considered to assess its pathogenesis and antibiotic resistance.

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Prevalence of SHV-extended spectrum β-lactamase producing carbapenem –resistantKlebsiellapneumoniae among patients with lower respiratory tractinfections in Babylon Province-Iraq.

International Journal of Research in Pharmaceutical Sciences ◽

10.26452/ijrps.v9ispl1.1299 ◽

2018 ◽

Vol 9 (SPL1) ◽

Author(s):

Fatima Moeen Abbas

Keyword(s):

Resistance Rate ◽

Combination Method ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Carbapenem Resistant ◽

Extended Spectrum ◽

Pcr Method ◽

Polymerase Chain ◽

Tract Infections ◽

Positive Results

This study was carried out to screen the prevalence of Klebsiella pneumoniae isolated from patients with lower respiratory tract infections in Babylon province.From December,2015 to the end of March,2016,a total of 100 sputum samples were collected from patients visited or hospitalized Merjan Teaching Hospital and Al- Hashimya General Hospital. Fifteenth (65%) isolates were identified as Klebsiellapneumoniae. All bacterial isolates were evaluated for extended spectrum β-lactamase (ESBL) production phenotypically using disk combination method. Eleven (73.3%) isolates were detected as ESBL-producers. Kirby-Bauer disk diffusion method was employed to determine resistance profile of ESBLs-positive isolates. Higher rates of resistance were observed for ampicillin and piperacillin antibiotics with (81.8%) and (72.7%) resistance rate, respectively, while the lowest rate was noticed for imipenem antibiotic (14.28%). Carbapenem-resistant isolates were investigated for blaSHV gene by Polymerase Chain Reaction (PCR) method, 2 (100%) isolates gave positive results.

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Occurrence of toxigenic Escherichia coli in raw milk cheese in Brazil

Arquivo Brasileiro de Medicina Veterinária e Zootecnia ◽

10.1590/s0102-09352007000200035 ◽

2007 ◽

Vol 59 (2) ◽

pp. 508-512 ◽

Cited By ~ 27

Author(s):

B.R. Paneto ◽

R.P. Schocken-Iturrino ◽

C. Macedo ◽

E. Santo ◽

J.M. Marin

Keyword(s):

Escherichia Coli ◽

Polymerase Chain Reaction ◽

Antimicrobial Agents ◽

Raw Milk ◽

Diffusion Method ◽

Chain Reaction ◽

Disk Diffusion Method ◽

E Coli ◽

Polymerase Chain ◽

Raw Milk Cheese

The occurrence of toxigenic Escherichia coli in raw milk cheese was surveyed in Middle Western Brazil. Fifty samples of cheese from different supermarkets were analyzed for E.coli. The isolates were serotyped and screened for the presence of verotoxigenic E. coli (VTEC) and enterotoxigenic E. coli (ETEC) by Polymerase Chain Reaction (PCR). The susceptibility to thirteen antimicrobial agents was evaluated by the disk diffusion method. E.coli were recovered from 48 (96.0%) of the samples. The serogroups identified were O125 (6.0%), O111 (4.0%), O55 (2.0%) and O119 (2.0%). Three (6.0%) and 1(2.0%) of the E.coli isolates were VTEC and ETEC, respectively. Most frequent resistance was observed to the following antimicrobials: cephalothin (60.0%), nalidixic acid (40.0%), doxycyclin (33.0%), tetracycline (31.0%) and ampicillin (29.0%).

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Molecular types, virulence profiles and antimicrobial resistance of Escherichia coli causing bovine mastitis

Veterinary Record Open ◽

10.1136/vetreco-2019-000369 ◽

2019 ◽

Vol 6 (1) ◽

pp. e000369 ◽

Cited By ~ 5

Author(s):

Magdalena Nüesch-Inderbinen ◽

Nadine Käppeli ◽

Marina Morach ◽

Corinne Eicher ◽

Sabrina Corti ◽

...

Keyword(s):

Escherichia Coli ◽

Bovine Mastitis ◽

Tetracycline Resistance ◽

Diffusion Method ◽

Sample Population ◽

Disk Diffusion Method ◽

E Coli ◽

Phylogenetic Grouping ◽

Resistance Rates ◽

Susceptibility Profiles

BackgroundEscherichia coli is an important aetiological agent of bovine mastitis worldwide.MethodsIn this study, 82 E. coli from bovine mastitis milk samples from 49 farms were analysed for their genetic diversity using phylogenetic grouping and multilocus sequence typing. The isolates were examined by PCR for a selection of virulence factors (VFs). Antimicrobial susceptibility profiles were assessed using the disk diffusion method.ResultsThe most prevalent phylogroups were group B1 (41.5 per cent of the isolates) and group A (30.5 per cent). A variety of 35 different sequence types (STs) were identified, including ST1125 (11 per cent), ST58 (9.8 per cent), ST10 (8.5 per cent) and ST88 (7.3 per cent). Aggregate VF scores (the number of unique VFs detected for each isolate) ranged from 1 to 3 for 63.4 per cent of the isolates and were at least 4 for 12.2 per cent. For 24.4 per cent of the isolates, the score was 0. The three most frequent VFs were traT, fyuA and iutA. The majority (72 per cent) of the isolates harboured traT. The majority (68.3 per cent) of the isolates were fully susceptible to all antimicrobials tested, with 22 per cent resistant to ampicillin and 14.6 per cent to tetracycline. Resistance rates were low for gentamicin (3.7 per cent), amoxicillin/clavulanic acid (2.4 per cent) and ceftiofur (1.2 per cent), respectively.ConclusionAmong the study’s sample population, E. coli strains were genotypically diverse, even in cows from the same farm, although some STs occurred more frequently than others. Susceptibility to clinically relevant compounds remained high.

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“COVID 19- Two Waves & More” What Have We Learnt?

International Journal of Medical Science and Diagnosis Research ◽

10.32553/ijmsdr.v5i12.885 ◽

2021 ◽

Vol 5 (12) ◽

Author(s):

Manuj Kumar Sarkar ◽

Subhra Dey ◽

Boudhayan Das Munshi

Keyword(s):

World Health Organisation ◽

Physical Distance ◽

World Health ◽

Chain Reaction ◽

Tissue Paper ◽

Hand Sanitizer ◽

First Case ◽

The World ◽

Polymerase Chain ◽

Bat Coronavirus

The first case of SARS-CoV2 admitted on 26th December 2019 in Central Hospital, Wuhan, China. Broncho-alveolar lavage and Polymerase chain reaction of the aspirate showed high abundance of a viral RNA which has 89.1 % nucleotide identity with bat coronavirus previously isolated in China. Soon human to human transmission was observed and the outbreak started spreading. World Health Organisation on 11th March 2020 declared it as pandemic. COVID 19, caused by SARS-CoV-2, a disease we are still struggling to contain. With vaccination drive throughout the world, though the severity in re-infection has come down, but there is still threat by the various variants which are arising from time to time in various countries. The most effective way of preventing the spread of the virus is to keep physical distance from others of at least 1 meter, wearing a well fitted mask, keep hands clean and use hand sanitizer frequently, stay in well ventilated place, avoid crowded place and cough into bent elbow or tissue paper and get vaccinated when once’s turn comes. Therefore, we urge people to follow COVID appropriate behaviour properly. Keywords: COVID 19, SARS-CoV2, COVID appropriate behaviour, Social Distancing

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Prevalence of Virulence Genes and Drug Resistance Profiles of Pseudomonas aeruginosa Isolated From Clinical Specimens

Jundishapur Journal of Microbiology ◽

10.5812/jjm.118452 ◽

2021 ◽

Vol 14 (8) ◽

Author(s):

Seyed Ali Bazghandi ◽

Mohsen Arzanlou ◽

Hadi Peeridogaheh ◽

Hamid Vaez ◽

Amirhossein Sahebkar ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Drug Resistance ◽

Antibiotic Resistance ◽

Virulence Genes ◽

Virulence Gene ◽

Clinical Isolates ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Clinical Specimens ◽

Resistance Rates

Background: Drug resistance and virulence genes are two key factors for the colonization of Pseudomonas aeruginosa in settings with high antibiotic pressure, such as hospitals, and the development of hospital-acquired infections. Objectives: The objective of this study was to investigate the prevalence of drug resistance and virulence gene profiles in clinical isolates of P. aeruginosa in Ardabil, Iran. Methods: A total of 84 P. aeruginosa isolates were collected from clinical specimens of Ardabil hospitals and confirmed using laboratory standard tests. The disk diffusion method was used for antibiotic susceptibility testing and polymerase chain reaction (PCR) for the identification of P. aeruginosa virulence genes. Results: The highest and the lowest antibiotic resistance rates of P. aeruginosa strains were against ticarcillin-clavulanate (94%) and doripenem (33.3%), respectively. In addition, the frequency of multidrug-resistant (MDR) P. aeruginosa was 55.9%. The prevalence of virulence factor genes was as follows: algD 84.5%, lasB 86.9%, plcH 86.9%, plcN 86.9%, exoU 56%, exoS 51.2%, toxA 81%, nan1 13.1%, and pilB 33.3%. A significant association was observed between resistance to some antibiotics and the prevalence of virulence genes in P. aeruginosa. Conclusions: Our results revealed a high prevalence of antibiotic resistance, especially MDR, and virulence-associated genes in clinical isolates of P. aeruginosa in Ardabil hospitals. Owing to the low resistance rates against doripenem, gentamicin, and tobramycin, these antibiotics are recommended for the treatment of infections caused by highly resistant and virulent P. aeruginosa strains.

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Prevalence and Antibiograms of Salmonella in Commercially Produced Crocodile meat in Zimbabwe

Tanzania Veterinary Journal ◽

10.4314/tvj.v36i1.1 ◽

2021 ◽

Vol 36 (1) ◽

pp. 1-14

Author(s):

A.Z. Nhidza ◽

C. Gufe ◽

J. Marumure ◽

Z. Makuvara ◽

T. Chisango ◽

...

Keyword(s):

Hazard Analysis ◽

Control Point ◽

Penicillin G ◽

Diffusion Method ◽

Biochemical Tests ◽

Disk Diffusion Method ◽

Critical Control Point ◽

Meat Samples ◽

Low Prevalence ◽

Susceptibility Profiles

The presence of Salmonella in food products and emergence of antibiotic resistance are the major challenges facing public health policies. A total of 2749 crocodile meat samples obtained from the Central Veterinary Laboratories in Zimbabwe were screened for Salmonella specieswere collected from three Zimbabwean commercial farms between the year 2012 and 2019 for a retrospective observational study to determine the prevalence and magnitude of antibiotics resistant Salmonella species in crocodile meat. The isolation of Salmonella was in accordance with the ISO 6579:2002 and the antibiotic susceptibility testing was carried out based on Clinical and Laboratory Standard Institute’s recommendations by means of the Kirby-Bauer disk diffusion method. SILAB Database was used to determine the prevalence of Salmonella species. Prevalence was stratified by year and farms. Twenty Salmonella isolates were identified using biochemical tests, and 15 were confirmed by polymerase chain reaction (PCR). Antimicrobial susceptibility profiles of the confirmed Salmonella isolates were examined using 14 antibiotics. The overall prevalence of Salmonella species in crocodile meat samples was 0.5%. The prevalence of Salmonella species ranged from 0.04% to 0.44% in the crocodile meat samples and annual prevalence ranged from 0.01% to 1%. The highest prevalence of Salmonella (4.4%) was recorded in the year 2012. Salmonella isolates from one of the three tested farms were resistant to Erythromycin (73.33%), Ampicillin (80%), and Penicillin G (100%). Generally, Salmonella isolates displayed lower resistance to Cefepime, Ceftriaxone, Amikacin, Tetracycline, Ertapenem, Florfenicol, and Erythromycin (0-53.33%) whereas all Salmonella isolates showed susceptibility to Cefepime, Ceftriaxone, Ertapenem, and Florfenicol. Although the study indicates low prevalence of Salmonella species in crocodile meat, there is a need for strict implementation of Hazard Analysis Critical Control Point (HACCP) to reduce contamination rates in meat and its products

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Vancomycin and high-level aminoglycoside resistance in Enterococcus species

Microbiology Research ◽

10.4081/mr.2016.6441 ◽

2016 ◽

Vol 7 (1) ◽

Cited By ~ 1

Author(s):

Seyda Ozarslan Kurtgoz ◽

Burcin Ozer ◽

Melek Inci ◽

Nizami Duran ◽

Erkan Yula

Keyword(s):

Vancomycin Resistance ◽

Automated System ◽

Diffusion Method ◽

Beta Lactamase ◽

Aminoglycoside Resistance ◽

Disk Diffusion Method ◽

Gradient Diffusion ◽

Gentamicin Resistance ◽

Polymerase Chain ◽

High Level

The aim of the study was to investigate vancomycin and high-level aminoglycoside resistance (HLAR) in Enterococcus species by phenotypic and genotypic methods. A hundred Enterococcus strains were included in the study. Antimicrobial susceptibilities of strains were investigated by automated system, betalactamase production was investigated by nitrocefin disks, vancomycin resistance and HLAR were investigated by gradient diffusion method (GDM) and disk diffusion method, respectively. For detection of vancomycin and high-level gentamicin resistance (HLGR) genes, polymerase chain reaction was used. Teicoplanin linezolid, vancomycin, ampicillin, penicillin are the most susceptible antibiotics and strains were detected not to produce beta lactamase. Vancomycin resistance was detected in ten isolates by automated system and in only five isolates by GDM. Five isolates carrying VanA gene were determined. The ratio of HLGR and high-level streptomycin resistance was found 40 and 63% respectively. aac (6’)-1eaph (2’’)-1a gene was detected in 58% of strains. E. faecium strains were found more resistant to the antibiotics than the other species. Beta lactamase was detected in none of strains. The automated system detected vancomycin resistance in more strains than GDM. Therefore it is concluded that strains, which were detected to be resistant to vancomycin, should be confirmed by GDM. The ratio of VanA gene in strains is consistent with other studies. The HLAR ratio was found in about half of strains. The ratio of aac(6’)-1e-aph(2’’)-1a gene, which is the most reported gene in our country and other countries and one of the HLGR genes investigated in our study, was detected 58%.

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Antimicrobial Resistance Profiles of Escherichia coli from Diarrheic Weaned Piglets after the Ban on Antibiotic Growth Promoters in Feed

Antibiotics ◽

10.3390/antibiotics9110755 ◽

2020 ◽

Vol 9 (11) ◽

pp. 755 ◽

Cited By ~ 1

Author(s):

Do Kyung-Hyo ◽

Byun Jae-Won ◽

Lee Wan-Kyu

Keyword(s):

Escherichia Coli ◽

Antimicrobial Resistance ◽

Diffusion Method ◽

Growth Promoters ◽

Disk Diffusion Method ◽

Pathogenic Escherichia Coli ◽

Before And After ◽

Amoxicillin Clavulanic Acid ◽

Antibiotic Growth Promoters ◽

Polymerase Chain

This study aimed to survey the antimicrobial resistance profiles of 690 pathogenic Escherichia coli isolates obtained from Korean pigs with symptoms of enteric colibacillosis between 2007 and 2017, while assessing the change in antimicrobial resistance profiles before and after the ban on antibiotic growth promoters (AGPs). Following the Clinical and Laboratory Standards Institute guidelines, the antimicrobial resistance phenotype was analyzed through the disk diffusion method, and the genotype was analyzed by the polymerase chain reaction. After the ban on AGPs, resistance to gentamicin (from 68.8% to 39.0%), neomycin (from 84.9% to 57.8%), ciprofloxacin (from 49.5% to 39.6%), norfloxacin (from 46.8% to 37.3%), and amoxicillin/clavulanic acid (from 40.8% to 23.5%) decreased compared to before the ban. However, resistance to cephalothin (from 51.4% to 66.5%), cefepime (from 0.0% to 2.4%), and colistin (from 7.3% to 11.0%) had increased. We confirmed a high percentage of multidrug resistance before (95.0%) and after (96.6%) the ban on AGPs. The AmpC gene was the most prevalent from 2007 to 2017 (60.0%), followed by the blaTEM gene (55.5%). The blaTEM was prevalent before (2007–2011, 69.3%) and after (2012–2017, 49.2%) the ban on AGPs. These results provide data that can be used for the prevention and treatment of enteric colibacillosis.

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