Category Archives: Antibiotic Resistance

Research – Bacteria Broadly-Resistant to Last Resort Antibiotics Detected in Commercial Chicken Farms

Posted on January 16, 2021 by | Leave a comment

MDPI

Resistance to last resort antibiotics in bacteria is an emerging threat to human and animal health. It is important to identify the source of these antimicrobial resistant (AMR) bacteria that are resistant to clinically important antibiotics and evaluate their potential transfer among bacteria. The objectives of this study were to (i) detect bacteria resistant to colistin, carbapenems, and β-lactams in commercial poultry farms, (ii) characterize phylogenetic and virulence markers of E. coli isolates to potentiate virulence risk, and (iii) assess potential transfer of AMR from these isolates via conjugation. Ceca contents from laying hens from conventional cage (CC) and cage-free (CF) farms at three maturity stages were randomly sampled and screened for extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae, carbapenem-resistant Acinetobacter (CRA), and colistin resistant Escherichia coli (CRE) using CHROMagar™ selective media. We found a wide-spread abundance of CRE in both CC and CF hens across all three maturity stages. Extraintestinal pathogenic Escherichia coli phylogenetic groups B2 and D, as well as plasmidic virulence markers iss and iutA, were widely associated with AMR E. coli isolates. ESBL-producing Enterobacteriaceae were uniquely detected in the early lay period of both CC and CF, while multidrug resistant (MDR) Acinetobacter were found in peak and late lay periods of both CC and CF. CRA was detected in CF hens only. blaCMY was detected in ESBL-producing E. coli in CC and CF and MDR Acinetobacter spp. in CC. Finally, the blaCMY was shown to be transferrable via an IncK/B plasmid in CC. The presence of MDR to the last-resort antibiotics that are transferable between bacteria in food-producing animals is alarming and warrants studies to develop strategies for their mitigation in the environment. View Full-Text

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Posted in Antibacterial, Antibiotic Resistance, antimicrobial resistance, Antimicrobials, E.coli, Enterobacteriaceae, ESBL, Food Micro Blog, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, Food Technology, microbial contamination, Microbiology, Research, Technology

Research – Prevalence, Concentration, and Antimicrobial Resistance Profiles of Salmonella Isolated from Florida Poultry Litter

Posted on December 20, 2020 by | Leave a comment

Journal of Food Protection

ABSTRACT

For over a decade, Salmonella contamination has increasingly led to outbreaks of foodborne illness associated with fresh produce. The use of untreated animal manures, or biological soil amendments of animal origin, to amend agricultural soils holds a risk of contamination from foodborne pathogens, such as Salmonella. This study was conducted to determine the prevalence, concentration, serotypes, and antimicrobial resistance profiles of Salmonella in poultry litter from Florida farms. Litter pH, total Kjeldahl nitrogen, total ammonia nitrogen, total phosphorus (P2O5), total potassium (K2O), moisture content, total solids, total ash, organic matter, and aerobic plate count (APC) were also measured. Litter samples (n = 54) were collected from 18 broiler farms across three seasons (spring, summer, and winter). Salmonella concentrations were enumerated using a most-probable-number (MPN) method, and antimicrobial susceptibility testing was performed. The prevalence of Salmonella in litter samples was 61.1%, with a geometric mean of 0.21 ± 20.7 MPN/g. Across all seasons, Salmonella concentrations were not influenced by the chemical, physical, or microbial properties measured. Recovered Salmonella isolates (n = 290) were grouped into serogroups O:4 (43.1%), O:7 (26.9%), O:8 (11.0%), O:1,3,10,19 (7.9%), and O:9,46 (7.2%). Serotyping Salmonella isolates (n = 47) resulted in 12 serotypes, with the most common being Typhimurium (27.7%), Kentucky (17.0%), Enteritidis (14.9%), and Mbandaka (14.9%). Antimicrobial resistance to tetracycline (29.8%), sulfisoxazole (23.4%), and streptomycin (14.9%) was observed. No isolates were resistant to more than two antimicrobial agents. This study provides valuable information for future risk assessments for the use of poultry litter as an untreated biological soil amendment of animal origin.

HIGHLIGHTS
  • Prevalence and concentration of Salmonella in Florida poultry litter were examined.
  • Serovars Typhimurium, Kentucky, Enteritidis, and Mbandaka were most common.
  • Antimicrobial resistance to tetracycline, sulfisoxazole, and streptomycin was seen.
  • Multidrug-resistant Salmonella isolates were not observed.

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Posted in Antibacterial, Antibiotic Resistance, antimicrobial resistance, food contamination, Food Hygiene, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, Food Pathogen, Food Safety, Research, Salmonella, Salmonella in Chicken

Research – Prevalence of Antibiotic-Resistant Escherichia coli Isolates from Local and Imported Retail Chicken Carcasses

Posted on December 19, 2020 by | Leave a comment

Journal of Food Protection

ABSTRACT

The spread of antibiotic resistance among bacterial strains has been associated with consumption of food contaminated with both pathogenic and nonpathogenic bacteria. The objective of this study was to determine the prevalence of antibiotic resistant Escherichia coli isolates in local and imported retail raw chicken meat in Qatar. A total of 270 locally produced (chilled) and imported (chilled or frozen) whole chicken carcasses were obtained from three Hypermarket stores in Qatar. The 216 E. coli isolates recovered from the chicken samples were subjected to antibiotic susceptibility testing with the disk diffusion method. Extended-spectrum β-lactamase (ESBL) production was evaluated with the double disk synergy test. Isolates harboring colistin resistance were identified with a multiplex PCR assay and DNA sequencing. Nearly 89% (192) of the 216 isolates were resistant to at least one of the 18 antibiotics tested. Isolates from local and imported chicken carcasses had relatively higher resistance to sulfamethoxazole (62% of isolates), tetracycline (59.7%), ampicillin and trimethoprim (52.3% each), ciprofloxacin (47.7%), cephalothin (45.4%), and colistin (31.9%). Less resistance was found to amoxicillin–clavulanic acid (6%), ceftriaxone (5.1%), nitrofurantoin (4.2%), piperacillin-tazobactam (4.2%), cefepime (2.3%), meropenem (1.4%), ertapenem (0.9%), and amikacin (0.9%). Nine isolates (4.2%) were ESBL producers, and 137 (63.4%) were multidrug resistant. The percentages of multidrug-resistant, ESBL-producing, and colistin resistant isolates were significantly higher among isolates from local chilled than from imported chilled and frozen chicken samples. Our findings indicate the high prevalence of antibiotic-resistant E. coli in chicken meat sold at retail in Qatar.

HIGHLIGHTS
  • A high prevalence of antibiotic resistant E. coli was found in retail chicken in Qatar.
  • Multidrug resistance was observed in 63.4% of the E. coli isolates.
  • Colistin resistance was observed in 31.9% of the E. coli isolates.
  • Contamination of chicken meat with antibiotic-resistant E. coli is a public health concern.

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Posted in Antibiotic Resistance, antimicrobial resistance, E.coli, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, microbial contamination, Microbiology, Research

Research – Antibiotic Resistance and Biofilm-Forming Ability in Enterococcal Isolates from Red Meat and Poultry Preparations

Posted on December 12, 2020 by | Leave a comment

MDPI

kswfoodworld biofilm

This study investigated the resistance to antibiotics and the capacity to form a biofilm of 200 isolates of enterococci isolated from raw preparations of beef (51 strains), pork (47), chicken (50), and turkey (52) acquired in north-western Spain. Fifteen antimicrobials of clinical importance were tested by the disc diffusion method. The average number of resistances per strain was 4.48 ± 1.59. If resistant strains were taken together with those showing reduced susceptibility, the total number of resistances per strain was 6.97 ± 2.02. Two isolates (1.0% of strains) were resistant to a single antibiotic, twenty-two isolates (11.0%) presented resistance to two, one strain (0.5%) was resistant to three, and 175 isolates (87.5%) showed a multiple drug-resistant phenotype (MDR; defined as no susceptibility to at least one agent from each of three or more antimicrobial categories). The prevalence of resistance varied between 0.5% (gentamicin) and 100% (kanamycin). All strains produced biofilm on polystyrene microwell plates, determined using crystal violet assay. Isolates were classified as having a weak (51 strains; average optical density at 580 nanometers -OD580– = 0.206 ± 0.033), moderate (78 strains; average OD580 = 0.374 ± 0.068), or strong (71 strains; average OD580 = 1.167 ± 0.621) ability to produce biofilm (p < 0.05). Isolates from beef preparations produced the most substantial (p < 0.05) biofilms. The results of this study indicate that meat and poultry preparations are major reservoirs of antibiotic-resistant enterococcal strains capable of forming a biofilm. In order for food-borne infections to be prevented, the importance of careful handling of these foodstuffs during preparation, avoiding cross-contamination, and ensuring thorough cooking, is stressed.

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Posted in Antibiotic Resistance, antimicrobial resistance, Biofilm, food contamination, Food Micro Blog, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, Food Safety, Food Technology, Research, Technology

Research – Variation of antibiotic resistance in Salmonella Enteritidis, Escherichia coli O157 :H7 , and Listeria monocytogenes after exposure to acid, salt, and cold stress

Posted on August 23, 2020 by | Leave a comment

Wiley Online

Abstract

Bacteria with antibiotic‐resistant could seriously threaten to human health, increasing the treatment cost for infections and negatively affecting treatment outcomes. Stress adaptation is one possible mechanism for the acquisition or enhancement of antibiotic resistance in bacteria as a result of cross‐protection. In this study, the effects of acid, salt, and cold stress on the antibiotic resistance of Salmonella Enteritidis, Listeria monocytogenes , and Escherichia coli O157:H7 were investigated using the disc diffusion method. For S. Enteritidis, acidic growth conditions increased resistance to ciprofloxacin and erythromycin (p  < .05), and addition of 4% NaCl to growth media decreased resistance to chloramphenicol (p  < .05). Irrespective of pH and the NaCl concentration of the growth medium, refrigerated E. coli O157:H7 showed increased resistance to amoxycillin, ciprofloxacin, gentamicin, streptomycin, and erythromycin (p  < .05). Acid‐adapted L. monocytogenes showed decreased the resistance to amoxycillin, ampicillin, chloramphenicol, ciprofloxacin, erythromycin, gentamicin, streptomycin, and tetracycline (p  < .05). In conclusion, prolonged exposure of foodborne pathogens to acid, salt, and cold stress alters their antibiotic resistance. However, the effect of acid, salt, and cold stress on bacterial antibiotic resistance depend on both the bacterial species and the specific antibiotic. Therefore, multiple factors need to be considered for a foodborne antimicrobial resistant risk assessment.

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Posted in Antibiotic Resistance, antimicrobial resistance, Antimicrobials, E.coli O157, E.coli O157:H7, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, Food Technology, Listeria monocytogenes, microbial contamination, Microbiological Risk Assessment, Microbiology, Research, Salmonella, Uncategorized

Research – Optimization on antimicrobial effects of surfactin against Bacillus cereus spore

Posted on July 11, 2020 by | Leave a comment

JFP

Abstract :The purpose of this study was to establish a three-variable bactericidal model of temperature, time, and concentration to determine the optimal conditions for Bacillus cereus  spore inactivation by surfactin. In order to obtain the binary regression equation of the inactivated spore model, a total of 17 simulations were performed using response surface methodology. The experimental results showed that the three factors each had a discernible but non-equal impact on the inactivation response value. Multiple regression analysis of experimental results using Design-Expert software yielded as the following equation: Optimal inactivation of spores was achieved by treatment with surfactin at a concentration of 4 mg/ml for 40 h at 53 °C, with the response value reaching 1.8. The spores were treated with surfactin under these conditions; the microstructural changes of spores were observed by scanning electron microscopy. We found that the structures of the outer wall of the spores were damaged, while the spores in the control sample showed no visible damage.

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Posted in Antibiotic Resistance, antimicrobial resistance, Antimicrobials, Bacillus, Bacillus cereus, Food Micro Blog, Food Microbiology Blog, Food Microbiology Research, microbial contamination, Microbiology, Research, Spores, Uncategorized

Research – Foodborne Klebsiella pneumoniae: Virulence Potential, Antibiotic Resistance, and Risks to Food Safety

Posted on July 4, 2020 by | Leave a comment

JFP

CDC Klebsiella

Image CDC

ABSTRACT

Gastrointestinal carriage of Klebsiella pneumoniae is a predisposing factor for liver abscess in several Asian countries. To determine whether hypervirulent K. pneumoniae in the gut may be transmitted through food, we screened a range of raw and ready-to-eat retail food by culture and recovered K. pneumoniae in 21% (147 of 698) of samples tested. Based on PCR, no K. pneumoniae isolates carried the rmpA gene linked to community-acquired pyogenic liver abscess, providing no evidence of a link between food and liver disease. However, phenotypic resistance to multiple antibiotic classes was seen through disk diffusion tests, and carriage of genetic elements (wcaG and capsule types K1, K2, and K54) associated with increased virulence (8%, 11 of 147) was observed by PCR. Multidrug-resistant isolates were from raw vegetables, chicken or pork liver, and a ready-to-eat poultry dish; one multidrug-resistant K. pneumoniae isolate from raw bean sprouts was resistant to a third-generation cephalosporin (ceftriaxone). Although K. pneumoniae may be present in food without causing harm, we found isolates belonging to the K1 capsular serotype coexisting with the wcaG gene, one also conferring multidrug resistance. K. pneumoniae that carry antibiotic resistance genes, regardless of pathogenicity, may increase the available genetic pool of resistance along the food chain. Hygienic food handling practices are necessary to lower risks of acquiring K. pneumoniae and other opportunistic pathogens.

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Posted in Antibiotic Resistance, antimicrobial resistance, Antimicrobials, Food Micro Blog, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, Klebsiella, microbial contamination, Microbiology, Research, Uncategorized

Research – Food safety risk posed to consumers of table eggs from layer farms in Gauteng Province, South Africa: Prevalence of Salmonella species and Escherichia coli , antimicrobial residues, and antimicrobial resistant bacteria

Posted on June 21, 2020 by | Leave a comment

Wiley Online hazegg.jpg

The study conducted on 39‐layer farms in Gauteng Province, South Africa determined the prevalence and resistance of enteropathogens, and antimicrobial residues in table eggs collected from the farms. Eggs were tested for the presence of bacteria using standard methods. The resistance of bacteria to eight antimicrobial agents was determined using the disc diffusion method. Antimicrobial residues were detected in table eggs using the microbial inhibition test, enzyme‐linked immunosorbent assay (ELISA), and high performance liquid chromatography (HPLC). Risk factors for egg contamination by bacteria and antimicrobial residues were determined through a questionnaire survey of farmers. The farm prevalence of Salmonella spp. and Escherichia coli in table eggs was 7.7 and 48.7%, respectively. Nineteen (48.7%) and 2 (5.1%) of eggshells and egg contents, respectively, were positive for E . coli but only eggshells yielded Salmonella species, 2.0% (4 of 196). Overall, 71.4% of 49 E . coli isolates exhibited resistance to one or more antimicrobial agents. The farm prevalence and egg content prevalence of antimicrobial residues was 2.6 and 0.5%, respectively, with the detection of sulfonamide (79 ppb) and oxytetracycline (106 ppb). The prevalence of resistant E . coli and Salmonella spp. and the occurrence of antimicrobial residues in egg content may pose food safety and therapeutic threats to consumers.

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Posted in Antibiotic Resistance, antimicrobial resistance, Antimicrobials, E.coli, Food Microbiology Research, Research, Salmonella, Salmonella in Eggs, Uncategorized

Research – Antimicrobial Resistance in Salmonella enterica Serovar Paratyphi B Variant Java in Poultry from Europe and Latin America

Posted on May 31, 2020 by | Leave a comment

CDC

Salmonellaa

Image CDC

Salmonella enterica serovar Paratyphi B variant Java sequence type 28 is prevalent in poultry and poultry meat. We investigated the evolutionary relatedness between sequence type 28 strains from Europe and Latin America using time-resolved phylogeny and principal component analysis. We sequenced isolates from Colombia, Guatemala, Costa Rica, and the Netherlands and complemented them with publicly available genomes from Europe, Africa, and the Middle East. Phylogenetic time trees and effective population sizes (Ne) showed separate clustering of strains from Latin America and Europe. The separation is estimated to have occurred during the 1980s. Ne of strains increased sharply in Europe around 1995 and in Latin America around 2005. Principal component analysis on noncore genes showed a clear distinction between strains from Europe and Latin America, whereas the plasmid gene content was similar. Regardless of the evolutionary separation, similar features of resistance to β-lactams and quinolones/fluoroquinolones indicated parallel evolution of antimicrobial resistance in both regions.

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Posted in Antibiotic Resistance, antimicrobial resistance, Antimicrobials, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, microbial contamination, Microbiology, Research, Uncategorized

Research -ECCMID studies probe resistant pathogens in pets, pet food, and people

Posted on April 21, 2020 by | Leave a comment

CIDRAP

Two studies by Portuguese scientists presented at the European Congress of Clinical Microbiology and Infectious Diseases (ECCMID) highlight concerns about the potential for transmission of multidrug-resistant (MDR) bacteria between companion animals and humans.

In one study, researchers from the University of Porto found high levels of MDR enterococci in raw-frozen dog food sold in the European Union. In another study, a household survey and molecular screening by researchers from the University of Lisbon found the colistin-resistance gene MCR-1 in two healthy humans and one dog with a skin infection.

But in a third study, researchers in Germany reported that pet ownership does not appear to be a significant risk factor for colonization with MDR organisms (MDROs).

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Posted in Antibiotic Resistance, antimicrobial resistance, Antimicrobials, food contamination, Food Hygiene, Food Illness, Food Inspections, Food Microbiology Research, Pet Food Testing, raw pet food, Research, Uncategorized