A Model to Investigate the Impact of Farm Practice on Antimicrobial Resistance in UK Dairy Farms

AbstractThe ecological and human health impact of antibiotic use and the related antimicrobial resistance (AMR) in animal husbandry is poorly understood. In many countries, there has been considerable pressure to reduce overall antibiotic use in agriculture or to cease or minimise use of human critical antibiotics. However, a more nuanced approach would consider the differential impact of use of different antibiotic classes; for example, it is not known whether reduced use of bacteriostatic or bacteriolytic classes of antibiotics would be of greater value. We have developed an ordinary differential equation model to investigate the effects of farm practice on the spread and persistence of AMR in the dairy slurry tank environment. We model the chemical fate of bacteriolytic and bacteriostatic antibiotics within the slurry and their effect on a population of bacteria, which are capable of resistance to both types of antibiotic. Through our analysis, we find that changing the rate at which a slurry tank is emptied may delay the proliferation of multidrug-resistant bacteria by up to five years depending on conditions. This finding has implications for farming practice and the policies that influence waste management practices. We also find that, within our model, the development of multidrug resistance is particularly sensitive to the use of bacteriolytic antibiotics, rather than bacteriostatic antibiotics, and this may be cause for controlling the usage of bacteriolytic antibiotics in agriculture.

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De-escalation of antimicrobial therapy in ICU settings with high prevalence of multidrug-resistant bacteria: a multicentre prospective observational cohort study in patients with sepsis or septic shock

Journal of Antimicrobial Chemotherapy ◽

10.1093/jac/dkaa375 ◽

2020 ◽

Vol 75 (12) ◽

pp. 3665-3674 ◽

Cited By ~ 3

Author(s):

Christina Routsi ◽

Aikaterini Gkoufa ◽

Kostoula Arvaniti ◽

Stelios Kokkoris ◽

Alexandros Tourtoglou ◽

...

Keyword(s):

Antimicrobial Resistance ◽

Antimicrobial Therapy ◽

Sofa Score ◽

Multivariate Regression Analysis ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

Antibiotic Resistant ◽

Number Of Patients ◽

Observational Cohort ◽

The Impact

Abstract Background De-escalation of empirical antimicrobial therapy, a key component of antibiotic stewardship, is considered difficult in ICUs with high rates of antimicrobial resistance. Objectives To assess the feasibility and the impact of antimicrobial de-escalation in ICUs with high rates of antimicrobial resistance. Methods Multicentre, prospective, observational study in septic patients with documented infections. Patients in whom de-escalation was applied were compared with patients without de-escalation by the use of a propensity score matching by SOFA score on the day of de-escalation initiation. Results A total of 262 patients (mean age 62.2 ± 15.1 years) were included. Antibiotic-resistant pathogens comprised 62.9%, classified as MDR (12.5%), extensively drug-resistant (49%) and pandrug-resistant (1.2%). In 97 (37%) patients de-escalation was judged not feasible in view of the antibiotic susceptibility results. Of the remaining 165 patients, judged as patients with de-escalation possibility, de-escalation was applied in 60 (22.9%). These were matched to an equal number of patients without de-escalation. In this subset of 120 patients, de-escalation compared with no de-escalation was associated with lower all-cause 28 day mortality (13.3% versus 36.7%, OR 0.27, 95% CI 0.11–0.66, P = 0.006); ICU and hospital mortality were also lower. De-escalation was associated with a subsequent collateral decrease in the SOFA score. Cox multivariate regression analysis revealed de-escalation as a significant factor for 28 day survival (HR 0.31, 95% CI 0.14–0.70, P = 0.005). Conclusions In ICUs with high levels of antimicrobial resistance, feasibility of antimicrobial de-escalation was limited because of the multi-resistant pathogens isolated. However, when de-escalation was feasible and applied, it was associated with lower mortality.

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Resistance determinants and their genetic context in enterobacteria from a longitudinal study of pigs reared under various husbandry conditions

Applied and Environmental Microbiology ◽

10.1128/aem.02612-20 ◽

2021 ◽

Author(s):

Dominic Poulin-Laprade ◽

Jean-Simon Brouard ◽

Nathalie Gagnon ◽

Annie Turcotte ◽

Alexandra Langlois ◽

...

Keyword(s):

Antimicrobial Resistance ◽

Efflux Pump ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

Production Cycle ◽

Antimicrobial Use ◽

Resistance Determinants ◽

Extended Spectrum ◽

Antimicrobial Resistance Genes ◽

The Impact

Pigs are major reservoirs of resistant Enterobacteriaceae that can reach humans through consumption of contaminated meat or vegetables grown in manure-fertilized soil. Samples were collected from sows during lactation and their piglets at five time points spanning the production cycle. Cefotaxime-resistant bacteria were quantified and isolated from feed, feces, manures and carcasses of pigs reared with penicillin-using or antibiotic-free husbandries. The isolates were characterized by antibiotic susceptibility testing, whole genome sequencing and conjugation assays. The extended spectrum β-lactamase (ESBL) phenotype was more frequent in isolates originating from antibiotic-free animals, while the bacteria isolated from penicillin-using animals were on average resistant to a greater number of antibiotics. The ESBL-encoding genes identified were blaCTX-M-1, blaCTX-M-15 and blaCMY-2 and they co-localised on plasmids with various genes encoding resistance to ß-lactams, co-trimoxazole, phenicols and tetracycline, all antibiotics used in pig production. Groups of genes conferring the observed resistance and the mobile elements disseminating multidrug resistance were determined. The observed resistance to ß-lactams was mainly due to the complementary actions of penicillin-binding proteins, an efflux pump and ß-lactamases. Most resistance determinants were shared by animals raised with or without antimicrobials. This suggests a key contribution of indigenous enterobacteria maternally transmitted along the sow lineage, regardless of antimicrobial use. It is unclear if the antimicrobial resistance observed in the enterobacteria populations of the commercial pig herds studied were present before the use of antibiotics, or the extent to which historical antimicrobial use exerted a selective pressure defining the resistant bacterial populations in farms using penicillin prophylaxis. Importance: Antimicrobial resistance is a global threat that needs to be fought on numerous fronts along the One Health continuum. Vast quantities of antimicrobials are used in agriculture to ensure animal welfare and productivity, and are arguably a driving force for the persistence of environmental and food-borne resistant bacteria. This study evaluated the impact of conventional, organic and other antibiotic-free husbandry practices on the frequency and nature of antimicrobial resistance genes and multidrug resistant enterobacteria. It provides knowledge about the relative contribution of specific resistance determinants to observed antibiotic resistance. It also showed the clear co-selection of genes coding for extended-spectrum beta-lactamases and genes coding for the resistance to antibiotics commonly used for prophylaxis or in curative treatments in pig operations.

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Impact of Medicated Feed on the Development of Antimicrobial Resistance in Bacteria at Integrated Pig-Fish Farms in Vietnam

Applied and Environmental Microbiology ◽

10.1128/aem.02975-10 ◽

2011 ◽

Vol 77 (13) ◽

pp. 4494-4498 ◽

Cited By ~ 35

Author(s):

Son Thi Thanh Dang ◽

Andreas Petersen ◽

Dung Van Truong ◽

Huong Thi Thanh Chu ◽

Anders Dalsgaard

Keyword(s):

Antimicrobial Resistance ◽

Animal Feed ◽

Animal Husbandry ◽

Pig Manure ◽

Resistant Bacteria ◽

Fish Farms ◽

Content Type ◽

E Coli ◽

Animal Excreta ◽

The Impact

ABSTRACTIntegrated livestock-fish aquaculture utilizes animal excreta, urine, and feed leftovers as pond fertilizers to enhance the growth of plankton and other microorganisms eaten by the fish. However, antimicrobial-resistant bacteria may be transferred and develop in the pond due to selective pressure from antimicrobials present in animal feed, urine, and feces. In an experimental pig-fish farm located in periurban Hanoi, Vietnam, nine piglets were provided feed containing 5 μg of tetracycline (TET)/kg pig weight/day and 0.45 μg of enrofloxacin (ENR)/kg pig weight/day during the second and fourth (last) months of the experiment. The aim of this study was to determine the association between the provision of pig feed with antimicrobials and the development of antimicrobial resistance, as measured in a total of 520Escherichia coliand 634Enterococcusstrains isolated from pig manure and water-sediment pond samples. MIC values for nalidixic acid (NAL) and ENR showed thatE. coliandEnterococcusspp. overall exhibited significant higher frequencies of resistance toward NAL and ENR during the 2 months when pigs were administered feed with antimicrobials, with frequencies reaching 60 to 80% in both water-sediment and manure samples. TET resistance for both indicators was high (>80%) throughout the study period, which indicates that TET-resistantE. coliandEnterococcusspp. were present in the piglets before the initiation of the experiment. PCR-based identification showed similar relative occurrences ofEnterococcus faecium,Enterococcus faecalis, and otherEnterococcusspp. in the water-sediment and manure samples, suggesting thatEnterococcusspp. isolated in the ponds originated mainly from the pig manure. The development of antimicrobial resistance in integrated animal husbandry-fish farms and possible transfers and the impact of such resistance on food safety and human health should be further assessed.

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Prevention and Control of Multidrug-Resistant Bacteria in The Netherlands and Germany—The Impact of Healthcare Structures

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17072337 ◽

2020 ◽

Vol 17 (7) ◽

pp. 2337

Author(s):

Robin Köck ◽

Karsten Becker ◽

Evgeny A. Idelevich ◽

Annette Jurke ◽

Corinna Glasner ◽

...

Keyword(s):

The Netherlands ◽

Antibiotic Use ◽

Multidrug Resistant ◽

Point Of View ◽

Resistant Bacteria ◽

The European Union ◽

Staffing Ratios ◽

Healthcare Associated ◽

And Control ◽

The Impact

The Netherlands and Germany are neighbouring countries within the European Union but are differently affected by multidrug-resistant microorganisms (MDRO). In this narrative review, we summarize data about antibiotic use, the occurrence of MDRO and healthcare-associated infections in these two countries, as well as data about organizational and structural differences between the Dutch and German healthcare systems. These results are discussed with a focus on whether or how the organization of healthcare influences MDRO prevention. We found that from the point of view of MDRO prevention, a higher density of inpatient care, a higher number of hospitals, a longer length of stay and lower staffing ratios might facilitate MDRO dissemination in German hospitals.

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Screening for Third-Generation Cephalosporin-Resistant Bacteria Reduces the Incidence on Late-Onset Sepsis and Antibiotic use in Neonates

Klinische Pädiatrie ◽

10.1055/a-1128-0524 ◽

2020 ◽

Vol 232 (04) ◽

pp. 203-209 ◽

Cited By ~ 1

Author(s):

Ann Carolin Longardt ◽

Brar Piening ◽

Katharina von Weizsäcker ◽

Christof Dame ◽

Christoph Bührer ◽

...

Keyword(s):

Late Onset ◽

Antibiotic Use ◽

Generation Cephalosporin ◽

Multidrug Resistant ◽

Matched Pair ◽

Resistant Bacteria ◽

Third Generation ◽

Contact Precautions ◽

Late Onset Sepsis ◽

The Impact

Abstract Background The extensive use of antibiotics is reflected by an increasing prevalence of infections with multidrug-resistant bacteria, including third-generation cephalosporin-resistant bacteria (3GCRB). For neonatal intensive care units screening and enhanced barrier precautions are recommended to control the spread of multidrug-resistant Gram-negative bacteria, while evidence for efficacy of barrier precautions remains scarce in a non-outbreak setting. Objective To determine the impact of a screening program for maternal 3GCRB colonization and the effects of contact precautions and cohort nursing, concerning the risk of neonatal late-onset sepsis (LOS) and antibiotic use rates (AURs). Study Design In a retrospective matched-pair cohort study, data of neonates exposed to maternal 3GCRB colonization were compared with findings in non-exposed neonates. Results Of 3,144 neonates admitted, 184 neonates born to 3GCRB-positive mothers were eligible. Among them, 37 (20%) became 3GCRB positive during hospital stay. 3GCRB-exposed infants had a lower rate of LOS (6.5 vs. 14.1%, p=0.03) and lower AURs in that time period compared to controls (mean 0.009 vs. 0.025, p=0.006). When started within the first 72h after birth, days of therapy with meropenem were significantly lower in non-exposed vs. 3GCRB-exposed infants (mean 0.13 vs. 0.42; p=0.002). No invasive infections with 3GCRB occurred. Conclusions Neonates of 3GCRB-positive mothers do not have an increased a priori risk for invasive 3GCRB infection and may benefit from enhanced contact precautions measures.

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Evaluation of Antibiotic Resistance in Bacterial Strains Isolated from Sewage of Slaughterhouses Located in Sicily (Italy)

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18189611 ◽

2021 ◽

Vol 18 (18) ◽

pp. 9611

Author(s):

Alessio Facciolà ◽

Antonino Virga ◽

Maria Eufemia Gioffrè ◽

Pasqualina Laganà

Keyword(s):

Antimicrobial Resistance ◽

Animal Husbandry ◽

Multidrug Resistant ◽

Resistance Rate ◽

Resistant Bacteria ◽

Bacterial Strains ◽

Antibiotic Resistant ◽

The Difference ◽

Wastewater Samples ◽

Almost All

Antimicrobial resistance is presently one of the most public health critical concerns. The frequent and often incorrect use of antibiotics in animal husbandry has led to the spread of antimicrobial resistance in this setting. Wastewater from slaughterhouses can be contaminated with multidrug-resistant bacteria, representing a possible cross-contamination route. We evaluated the presence of antibiotic-resistant bacteria in wastewater samples from slaughterhouses located in an Italian region. Specifically, 18 slaughterhouses were included in the study. Of the tested samples, 40 bacterial strains were chosen, identified, and tested for antibiotic susceptibility. Pseudomonas spp., Proteus spp., Enterobacter spp., Aeromonas spp., and Citrobacter spp. were the most detected genera. The most resistant strains were on average those belonging to Enterobacter spp. The highest resistance rate was recorded for macrolides. Among β-lactams, penicillins and cephalosporins were by far the molecules towards which the highest resistance was detected. A very interesting finding is the difference found in strains detected in wastewater from poultry slaughterhouses, in which higher levels for almost all the considered drugs were detected compared to those from ungulates slaughterhouses. Our results indicate wastewater from slaughterhouses as a potential vehicle of resistant bacteria and highlight the importance of correct management of these kinds of waters.

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Multiresistant Bacteria Isolated from Intestinal Faeces of Farm Animals in Austria

Antibiotics ◽

10.3390/antibiotics10040466 ◽

2021 ◽

Vol 10 (4) ◽

pp. 466

Author(s):

Herbert Galler ◽

Josefa Luxner ◽

Christian Petternel ◽

Franz F. Reinthaler ◽

Juliana Habib ◽

...

Keyword(s):

Meat Products ◽

Animal Husbandry ◽

Multidrug Resistant ◽

Farm Animals ◽

Resistant Bacteria ◽

Antibiotic Resistant Bacteria ◽

Antibiotic Resistant ◽

E Coli ◽

Multiresistant Bacteria ◽

Vancomycin Resistant

In recent years, antibiotic-resistant bacteria with an impact on human health, such as extended spectrum β-lactamase (ESBL)-containing Enterobacteriaceae, methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE), have become more common in food. This is due to the use of antibiotics in animal husbandry, which leads to the promotion of antibiotic resistance and thus also makes food a source of such resistant bacteria. Most studies dealing with this issue usually focus on the animals or processed food products to examine the antibiotic resistant bacteria. This study investigated the intestine as another main habitat besides the skin for multiresistant bacteria. For this purpose, faeces samples were taken directly from the intestines of swine (n = 71) and broiler (n = 100) during the slaughter process and analysed. All samples were from animals fed in Austria and slaughtered in Austrian slaughterhouses for food production. The samples were examined for the presence of ESBL-producing Enterobacteriaceae, MRSA, MRCoNS and VRE. The resistance genes of the isolated bacteria were detected and sequenced by PCR. Phenotypic ESBL-producing Escherichia coli could be isolated in 10% of broiler casings (10 out of 100) and 43.6% of swine casings (31 out of 71). In line with previous studies, the results of this study showed that CTX-M-1 was the dominant ESBL produced by E. coli from swine (n = 25, 83.3%) and SHV-12 from broilers (n = 13, 81.3%). Overall, the frequency of positive samples with multidrug-resistant bacteria was lower than in most comparable studies focusing on meat products.

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Rethinking Manure Application: Increase in Multidrug-Resistant Enterococcus spp. in Agricultural Soil Following Chicken Litter Application

Microorganisms ◽

10.3390/microorganisms9050885 ◽

2021 ◽

Vol 9 (5) ◽

pp. 885

Author(s):

Dorcas Oladayo Fatoba ◽

Akebe Luther King Abia ◽

Daniel G. Amoako ◽

Sabiha Y. Essack

Keyword(s):

Antimicrobial Resistance ◽

Agricultural Soil ◽

Multidrug Resistant ◽

Diffusion Method ◽

Resistant Bacteria ◽

Manure Application ◽

Unamended Soil ◽

Enterococcus Spp ◽

Chicken Litter ◽

Amended Soil

The current study investigated the impact of chicken litter application on the abundance of multidrug-resistant Enterococcus spp. in agricultural soil. Soil samples were collected from five different strategic places on a sugarcane farm before and after manure application for four months. Chicken litter samples were also collected. Enterococci were enumerated using the Enterolert®/Quanti-Tray 2000® system and confirm and differentiated into species using real-time PCR. The antibiotic susceptibility profile of the isolates was determined using the disk diffusion method following the European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines. The overall mean bacterial count was significantly higher (p < 0.05) in manure-amended soil (3.87 × 107 MPN/g) than unamended soil (2.89 × 107 MPN/g). Eight hundred and thirty-five enterococci (680 from soil and 155 from litter) were isolated, with E. casseliflavus being the most prevalent species (469; 56.2%) and E. gallinarum being the least (16; 1.2%). Approximately 56% of all the isolates were resistant to at least one antibiotic tested, with the highest resistance observed against tetracycline (33%) and the lowest against chloramphenicol (0.1%); 17% of E. faecium were resistant to quinupristin-dalfopristin. Additionally, 27.9% (130/466) of the isolates were multidrug-resistant, with litter-amended soil harbouring more multidrug-resistant (MDR) isolates (67.7%; 88/130) than unamended soil (10.0%; 13/130). All isolates were susceptible to tigecycline, linezolid and gentamicin. About 7% of the isolates had a multiple antimicrobial resistance index > 0.2, indicative of high antibiotic exposure. Although organic fertilizers are regarded as eco-friendly compared to chemical fertilizers for improving soil fertility, the application of untreated animal manure could promote the accumulation of antibiotics and their residues and antibiotic-resistant bacteria in the soil, creating an environmental reservoir of antimicrobial resistance, with potential human and environmental health risks.

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Liposomes as Antibiotic Delivery Systems: A Promising Nanotechnological Strategy against Antimicrobial Resistance

Molecules ◽

10.3390/molecules26072047 ◽

2021 ◽

Vol 26 (7) ◽

pp. 2047

Author(s):

Magda Ferreira ◽

Maria Ogren ◽

Joana N. R. Dias ◽

Marta Silva ◽

Solange Gil ◽

...

Keyword(s):

Antimicrobial Resistance ◽

Bacterial Infections ◽

Private Investment ◽

Therapeutic Index ◽

Multidrug Resistant ◽

Current Treatment ◽

Delivery Systems ◽

Resistant Bacteria ◽

Bacterial Cells ◽

Antimicrobial Drugs

Antimicrobial drugs are key tools to prevent and treat bacterial infections. Despite the early success of antibiotics, the current treatment of bacterial infections faces serious challenges due to the emergence and spread of resistant bacteria. Moreover, the decline of research and private investment in new antibiotics further aggravates this antibiotic crisis era. Overcoming the complexity of antimicrobial resistance must go beyond the search of new classes of antibiotics and include the development of alternative solutions. The evolution of nanomedicine has allowed the design of new drug delivery systems with improved therapeutic index for the incorporated compounds. One of the most promising strategies is their association to lipid-based delivery (nano)systems. A drug’s encapsulation in liposomes has been demonstrated to increase its accumulation at the infection site, minimizing drug toxicity and protecting the antibiotic from peripheral degradation. In addition, liposomes may be designed to fuse with bacterial cells, holding the potential to overcome antimicrobial resistance and biofilm formation and constituting a promising solution for the treatment of potential fatal multidrug-resistant bacterial infections, such as methicillin resistant Staphylococcus aureus. In this review, we aim to address the applicability of antibiotic encapsulated liposomes as an effective therapeutic strategy for bacterial infections.

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Management of superficial and deep surgical site infection: an international multidisciplinary consensus

Updates in Surgery ◽

10.1007/s13304-021-01029-z ◽

2021 ◽

Author(s):

Gabriele Sganga ◽

Mohamed Baguneid ◽

Pascal Dohmen ◽

Evangelos J. Giamarellos-Bourboulis ◽

Emilio Romanini ◽

...

Keyword(s):

Length Of Hospital Stay ◽

Surgical Site Infections ◽

Early Discharge ◽

Multidrug Resistant ◽

Steering Committee ◽

Resistant Bacteria ◽

Modified Delphi ◽

Hospital Stays ◽

New Treatment ◽

The Impact

AbstractSurgical site infections represent a considerable burden for healthcare systems. To obtain a consensus on the impact and future clinical and economic needs regarding SSI management in an era of multidrug resistance. A modified Delphi method was used to obtain consensus among experts from five European countries. The Delphi questionnaire was assembled by a steering committee, verified by a panel of experts and administered to 90 experts in 8 different surgical specialities (Abdominal, Cancer, Cardiac, General surgery, Orthopaedic, Thoracic, Transplant and Vascular and three other specialities (infectious disease, internal medicine microbiology). Respondents (n = 52) reached consensus on 62/73 items including that resistant pathogens are an increasing matter of concern and increase both treatment complexity and the length of hospital stay. There was strong positive consensus on the cost-effectiveness of early discharge (ED) programs, improvement of quality of life with ED and association between increased length of stay and economic burden to the hospital. However, established ED protocols were not widely available in their hospitals. Respondents expressed a positive consensus on the usefulness of antibiotics that allow ED. Surgeons are aware of their responsibility in an interdisciplinary team for the treatment of SSI, and of the impact of multidrug-resistant bacteria in the context of SSI. Reducing the length of hospital stays by applying ED protocols and implementing new treatment alternatives is crucial to reduce harm to patients and costs for the hospital.

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