Contamination of post-harvest poultry products with multidrug resistant Staphylococcus aureus in Maryland-Washington DC metro area

Detection of clinically relevant antibiotic-resistant bacteria in shared fomites, waste water and municipal solid wastes disposed near residential areas of a Nigerian city

Studies investigating environmental hotspots of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) in Nigeria are limited. This study was designed to assess various environmental sources and commonly touched surfaces as potential carriers of ARB and ARGs with implications for public health. A total of 392 samples, including sewage (36), sludge (36), diapers (20), plastics (20), water sachet polythene bags (20), food wastes (20), soil beneath dump sites (20), and frequently touched surfaces such as restroom floors (80), corridors (24), door handles (56), and room floors and walls (60), were collected and screened for the presence of resistant bacteria carrying genes such as bla KPC, bla NDM-1, bla CMY-2, bla IMP, bla OXA66 and MecA. Additionally, we employed standard techniques to detect methicillin-resistant Staphylococcus aureus (MRSA) and extended-spectrum β-lactamase (ESBL)-producing Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Acinetobacter baumannii . We also evaluated the effectiveness of routine disinfection procedures in eliminating ARB from restroom floors. Our findings revealed that sewage, sludge, diapers, food wastes and restroom floors are frequently contaminated with highly and moderately resistant strains of E. coli, K. pneumoniae, P. aeruginosa and MRSA. Notably, we identified two variants of the bla OXA51-like gene (bla OXA-66 and bla OXA-180) in A. baumannii isolated from these environmental sources. Furthermore, we detected seven ESBL- K. pneumoniae , five ESBL- A. baumannii , two ESBL- E. coli and one ESBL- P. aeruginosa , all carrying one or more ARGs (bla KPC, bla NDM-1, bla CMY-2), in isolates recovered from sewage, sludge, restroom floors and plastics. It is of note that ARB persisted on restroom floors even after disinfection procedures. In conclusion, this study highlights that environmental wastes indiscriminately discarded in residential areas and shared surfaces among individuals are heavily colonized by ARB carrying ARGs of significant public health importance.

Prevalence of antimicrobial resistance genes and its association with restricted antimicrobial use in food-producing animals: a systematic review and meta-analysis

BACKGROUND

There is ongoing debate regarding potential associations between restrictions of antimicrobial use and prevalence of antimicrobial resistance (AMR) in bacteria.

OBJECTIVES

To summarize the effects of interventions reducing antimicrobial use in food-producing animals on the prevalence of AMR genes (ARGs) in bacteria from animals and humans.

METHODS

We published a full systematic review of restrictions of antimicrobials in food-producing animals and their associations with AMR in bacteria. Herein, we focus on studies reporting on the association between restricted antimicrobial use and prevalence of ARGs. We used multilevel mixed-effects models and a semi-quantitative approach based on forest plots to summarize findings from studies.

RESULTS

A positive effect of intervention [reduction in prevalence or number of ARGs in group(s) with restricted antimicrobial use] was reported from 29 studies for at least one ARG. We detected significant associations between a ban on avoparcin and diminished presence of the vanA gene in samples from animals and humans, whereas for the mecA gene, studies agreed on a positive effect of intervention in samples only from animals. Comparisons involving mcr-1, blaCTX-M, aadA2, vat(E), sul2, dfrA5, dfrA13, tet(E) and tet(P) indicated a reduced prevalence of genes in intervention groups. Conversely, no effects were detected for β-lactamases other than blaCTX-M and the remaining tet genes.

CONCLUSIONS

The available body of scientific evidence supported that restricted use of antimicrobials in food animals was associated with an either lower or equal presence of ARGs in bacteria, with effects dependent on ARG, host species and restricted drug.

[Methicillin-resistant Staphylococcus aureus in the Americas: systematic review and metanalysis of prevalence in food-producing animalsStaphylococcus aureus resistente a la meticilina en la Región de las Américas: revisión sistemática y metanálisis de la prevalencia en la actividad agropecuaria]

OBJECTIVE

To determine the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in animals used to produce foods in the Americas.

METHOD

A systematic literature review was performed in the following databases: Scopus, Web of Science, MEDLINE, EMBASE, and Virtual Health Library. Articles published in the past 10 years, without language limits, were selected. The outcome of interest was the prevalence of MRSA in food-producing animals. Prevalence rates were meta-analyzed in grouped random effects models using the DerSimonian and Laird method. The geographic distribution of MRSA and the time trend of resistance were also analyzed.

RESULTS

Of 19 studies included, 11 were performed in the United States and 11 analyzed pig samples. Five studies were performed in South America. The samples analyzed in the studies were collected in farming, processing, and retail sites. MRSA prevalence in the Americas was 7.6% (95%CI: 5.6-9.5%), and was higher in pigs [12.6% (95%CI: 7.0-18.2%)] followed by bovine cattle [2.4% (95%CI: 1.2-3.7%)] and poultry [1.8% (95CI%: 0.3-3.4%)]. MRSA prevalence was higher in pigs in North America and bovine cattle in Latin America. There was no significant variation in MRSH prevalence along the 10-year period analyzed.

CONCLUSIONS

MRSA prevalence in food-producing animals in the Americas was higher in pigs, without significant changes across time.

The Remarkable Effect of Potassium Iodide in Eosin and Rose Bengal Photodynamic Action against Salmonella Typhimurium and Staphylococcus aureus

Antimicrobial photodynamic therapy (aPDT) has been shown as a promising technique to inactivate foodborne bacteria, without inducing the development of bacterial resistance. Knowing that addition of inorganic salts, such as potassium iodide (KI), can modulate the photodynamic action of the photosensitizer (PS), we report in this study the antimicrobial effect of eosin (EOS) and rose bengal (RB) combined with KI against Salmonella enterica serovar Typhimurium and Staphylococcus aureus. Additionally, the possible development of bacterial resistance after this combined aPDT protocol was evaluated. The combination of EOS or RB, at all tested concentrations, with KI at 100 mM, was able to efficiently inactivate S. Typhimurium and S. aureus. This combined approach allows a reduction in the PS concentration up to 1000 times, even against one of the most common foodborne pathogenics, S. Typhimurium, a gram-negative bacterium which is not so prone to inactivation with xanthene dyes when used alone. The photoinactivation of S. Typhimurium and S. aureus by both xanthenes with KI did not induce the development of resistance. The low price of the xanthene dyes, the non-toxic nature of KI, and the possibility of reducing the PS concentration show that this technology has potential to be easily transposed to the food industry.

Comparison of different approaches to antibiotic restriction in food-producing animals: stratified results from a systematic review and meta-analysis

BACKGROUND

We have previously reported, in a systematic review of 181 studies, that restriction of antibiotic use in food-producing animals is associated with a reduction in antibiotic-resistant bacterial isolates. While informative, that report did not concretely specify whether different types of restriction are associated with differential effectiveness in reducing resistance. We undertook a sub-analysis of the systematic review to address this question.

METHODS

We created a classification scheme of different approaches to antibiotic restriction: (1) complete restriction; (2) single antibiotic-class restriction; (3) single antibiotic restriction; (4) all non-therapeutic use restriction; (5) growth promoter and prophylaxis restriction; (6) growth promoter restriction and (7) other/undetermined. All studies in the original systematic review that were amenable to meta-analysis were included into this substudy and coded by intervention type. Meta-analyses were conducted using random effects models, stratified by intervention type.

RESULTS

A total of 127 studies were included. The most frequently studied intervention type was complete restriction (n=51), followed by restriction of non-therapeutic (n=33) and growth promoter (n=19) indications. None examined growth promoter and prophylaxis restrictions together. Three and seven studies examined single antibiotic-class and single antibiotic restrictions, respectively; these two intervention types were not significantly associated with reductions in antibiotic resistance. Though complete restrictions were associated with a 15% reduction in antibiotic resistance, less prohibitive approaches also demonstrated reduction in antibiotic resistance of 9%-30%.

CONCLUSION

Broad interventions that restrict global antibiotic use appear to be more effective in reducing antibiotic resistance compared with restrictions that narrowly target one specific antibiotic or antibiotic class. Importantly, interventions that allow for therapeutic antibiotic use appear similarly effective compared with those that restrict all uses of antibiotics, suggesting that complete bans are not necessary. These findings directly inform the creation of specific policies to restrict antibiotic use in food-producing animals.

Examination of unintended consequences of antibiotic use restrictions in food-producing animals: Sub-analysis of a systematic review

Antimicrobial resistance is considered one of the greatest threats to global and public health today. The World Health Organization, the Food and Agriculture Organization, and the World Organisation for Animal Health, known as the Tripartite Collaboration, have called for urgent action. We have previously published a systematic review of 181 studies, demonstrating that interventions that restrict antibiotic use in food-producing animals are associated with a reduction in antibiotic resistant bacterial isolates in both animals and humans. What remains unknown, however, are whether (and what) unintended consequences may arise from such interventions. We therefore undertook a sub-analysis of the original review to address this research question. A total of 47 studies described potential consequences of antibiotic restrictions. There were no consistent trends to suggest clear harm. There may be increased bacterial contamination of food products, the clinical significance of which remains unclear. There is a need for rigorous evaluation of the unintended consequences of antibiotic restrictions in human health, food availability, and economics, given their possible widespread implications.

Characterization of bacteriophages and their carriage in Staphylococcus aureus isolated from broilers in Poland

1. The objective of this study was the isolation and morphological characterization of temperate bacteriophages induced from Staphylococcus aureus strains isolated from clinical samples from broiler chickens and turkeys. 2. Eighty-five S. aureus strains were tested for susceptibility to oxacillin in order to determine which were methicillin resistant (MRSA). A total of 24 strains showed resistance to methicillin. 3. Thirty-one bacteriophages that were lytic against S. aureus strains were isolated and the host range of the bacteriophages was evaluated. Based on the presence of a specific nucleotide sequence, molecular identification of bacteriophages was performed and the presence of genes responsible for the production of classical enterotoxins (A-E) was also analysed. 4. All the isolated bacteriophages had an icosahedral head and a long, thin, non-contractile flexible tail, characteristic of the family Siphoviridae of the order Caudovirales. Based on multiplex PCR results, the phages were found to belong to serogroups A, B and F (Fa, Fb subgroup), which include mostly temperate phages infecting S. aureus. 5. The titre of the phages ranged from 10^-4 to 10^-9 PFU/ml. The bacteriophages exhibited strong lytic properties against some of the strains of Staphylococcus. The broadest spectrum of activity against the strains was observed in the case of phages sa2, sa3, sa6, sa12, sa15 and sa21. 6. The PCR results showed that of the 31 bacteriophage DNA samples, 4 (12.9%) appeared to have enterotoxigenic genes.

Food Safety at Farmers' Markets: A Knowledge Synthesis of Published Research

Farmers' markets are increasingly popular venues in North America for the sale of fresh produce and other foods. However, the nature of their operation can present possible food safety issues, challenges, and risks to consumers. A knowledge synthesis was conducted to identify, characterize, and summarize published research on the microbial food safety issues and implications associated with farmers' markets. A scoping review was conducted using the following steps: comprehensive search strategy, relevance screening of abstracts, and characterization of relevant articles. Two subsets of data were prioritized for more detailed systematic review (data extraction and risk-of-bias assessment) and meta-analysis: (i) studies comparing the microbial safety of foods from farmers' markets versus other sources and (ii) studies evaluating the use of food safety practices at farmers' markets. Overall, 83 relevant studies were identified. The majority of studies were published as journal articles (64%), used a cross-sectional design (81%), and were conducted in the United States (78%). Most studies (39%; n = 32) investigated stakeholder, mostly consumer (n = 22), attitudes toward food safety at farmers' markets. Limited but heterogeneous evidence indicated a higher prevalence of Campylobacter and Salmonella in chicken meat from farmers' markets versus other retail sources, but there was no difference in the microbial contamination of fresh produce. Studies evaluating the use of food safety practices at farmers' markets identified some gaps; for example, the average prevalence of vendor hand washing was 4% (95% confidence interval: 0 to 11%; I² = 27%; n = 5 studies). Twelve foodborne outbreaks and case reports were identified, resulting in a total of 411 illnesses, 38 hospitalizations, and two deaths from 1994 to 2016. Only five intervention studies were identified. Key knowledge gaps and areas warranting future research, training, and education are highlighted and discussed.

Antimicrobial-resistant Staphylococcus aureus and MRSA prevalence among Korean families and household items

One-hundred-and-seventy-nine Staphylococcus aureus strains, collected from a total of 825 resident and household item samples in Korean homes nationwide, were tested, to survey the spread of antimicrobial-resistant S. aureus including the methicillin-resistant S. aureus (MRSA) strain. Antimicrobial resistance to sulfamethoxazole-trimethoprim (0.0%), teicoplanin (0.0%), tetracycline, vancomycin (0.0%,) chloramphenicol (0.0%), ciprofloxacin (1.1%), clindamycin (1.1%), amikacin (2.2%), gentamicin (8.4%), oxacillin (17.9%), erythromycin (21.8%), ampicillin (96.6%) and penicillin (96.6%), was detected by disk diffusion method and 7.3% (13/179) of the antimicrobial-resistant isolates, were multi-drug resistant (resistant to ≥3 antimicrobial classes). Nine of 32 oxacillin-resistant strains, were positive for the mecA gene and identified as MRSA, in 4 residents and 4 loofah samples, by polymerase chain reaction. These findings provide public health information and contribute to preventing circulation of antimicrobial-resistant strains in community settings including healthy homes.

Polymerase chain reaction detection of genes responsible for multiple antibiotic resistance Staphylococcus aureus isolated from food of animal origin in Egypt

Aim:

The aim of our study was polymerase chain reaction (PCR) detection of the genes responsible for the multiple antibiotic resistance S. aureus isolated from food of animal origin in Egypt.

Materials and Methods:

A total of 125 samples were randomly collected from milk, meat, and their products from Giza and Beni-Suef Governorates markets. The S. aureus isolates were subjected to antimicrobial sensitivity tests using four antibacterial disks (Oxoid), and then the polymerase chain reaction (PCR) was performed for detection of antibiotic resistance genes.

Results:

Out of 125 samples, 19 S. aureus isolates were detected. All detected isolates were multiple drug resistance (MDR). The penicillin-, erythromycin-, kanamycin-, and tetracycline-resistant isolates were examined by PCR for resistance genes blaZ, (msrA, ermB, and ermC), aac(6’)aph (2”), and tetK. The isolates harbored these resistance genes with percentage of 100% (100%, 0%, and 100%), 62.5%, and 100%, respectively.

Conclusion:

Contaminated foods of animal origin may represent a source of MDR S. aureus that can be a major threat to public health.

Prevalence of the Antibiotic Resistance Genes in Coagulase-Positive-and Negative-Staphylococcus in Chicken Meat Retailed to Consumers

The use of antibiotics in farm management (growing crops and raising animals) has become a major area of concern. Its implications is the consequent emergence of antibiotic resistant bacteria (ARB) and accordingly their access into the human food chain with passage of antibiotic resistance genes (ARG) to the normal human intestinal microbiota and hence to other pathogenic bacteria causative human disease. Therefore, we pursued in this study to unravel the frequency and the quinolone resistance determining region, mecA and cfr genes of methicillin-susceptible Staphylococcus aureus (MSSA), methicillin-resistant S. aureus (MRSA), methicillin-resistant coagulase-negative staphylococci (MRCNS) and methicillin-susceptible coagulase-negative staphylococci (MSCNS) isolated from the retail trade of ready-to-eat raw chicken meat samples collected during 1 year and sold across the Great Cairo area. The 50 Staphylococcus isolated from retail raw chicken meat were analyzed for their antibiotic resistance phenotypic profile on 12 antibiotics (penicillin, oxacillin, methicillin, ampicillin-sulbactam, erythromycin, tetracycline, clindamycin, gentamicin, ciprofloxacin, chloramphenicol, sulfamethoxazole-trimethoprim, and vancomycin) and their endorsement of the quinolone resistance determining region, mecA and cfr genes. The isolation results revealed 50 isolates, CPS (14) and CNS (36), representing ten species (S. aureus, S. hyicus, S. epidermedius, S. lugdunensis, S. haemolyticus, S. hominus, S. schleiferi, S. cohnii, S. intermedius, and S. lentus). Twenty seven isolates were methicillin-resistant. Out of the characterized 50 staphylococcal isolates, three were MRSA but only 2/3 carried the mecA gene. The ARG that bestows resistance to quinolones, β-lactams, macrolides, lincosamides, and streptogramin B [MLS(_B)] in MRSA and MR-CNS were perceived. According to the available literature, the present investigation was a unique endeavor into the identification of the quinolone-resistance-determining-regions, the identification of MRSA and MR-CNS from retail chicken meat in Egypt. In addition, these isolates might indicate the promulgation of methicillin, oxacillin and vancomycin resistance in the community and imply food safety hazards.