Prudent Use Research Articles

Antimicrobial Resistance Profiles of Escherichia coli Isolated from Food Animal Carcasses During 2010-2023 in South Korea.

Antimicrobial-resistant bacterial contamination of meat poses a significant global public health risk. We aimed to determine antimicrobial resistance profiles and trends of Escherichia coli recovered from carcasses of healthy food-producing animals in South Korea during 2010-2023. In total, 4748 E. coli isolates obtained from cattle (n = 1582), pigs (n = 1572), and chickens (n = 1594) were assessed for susceptibility to 12 antimicrobials. Antimicrobial resistance was different among samples. Overall, antimicrobial resistance was high in pigs and chicken carcasses. More than about 80% of isolates from pigs and chickens exhibited resistance to one or more antimicrobials. Among the tested antimicrobials, resistance to ampicillin, chloramphenicol, streptomycin, and tetracycline was significantly higher in pigs and chickens compared with cattle (p < 0.05). Moreover, chicken isolates showed much higher resistance to nalidixic acid and ciprofloxacin than other samples. Resistance to critically important antimicrobials, colistin, remained less than about 1%, while resistance to ceftiofur showed increased trends in pig and chicken samples. Higher multidrug-resistant (MDR) isolates were identified in chickens and pigs compared with cattle (p < 0.05). Furthermore, most MDR patterns include streptomycin and tetracycline resistance. MDR E. coli contaminating meat during slaughter can be transmitted to humans via the food chain. Thus, prudent use of antimicrobials and proper hygienic practices are urgently needed to reduce the risk of transmission.

Optimizing antibiotic stewardship and reducing antimicrobial resistance in Central Asia: A study protocol for evidence-based practice and policy.

Antimicrobial resistance (AMR) poses a significant global health challenge, prompting the World Health Organization (WHO) to stress the importance of monitoring antibiotic consumption and sales to address AMR effectively. This study protocol aims to optimize antibiotic stewardship and combat AMR in Central Asia through evidence-based practices and policies. The protocol includes objectives such as conducting systematic reviews of interventions to promote judicious antibiotic use, assessing antibiotic consumption trends, and investigating antibiotic overuse practices among healthcare providers. The study aims to raise awareness among stakeholders to enhance appropriate antibiotic prescribing practices. By establishing regulatory frameworks, monitoring policies' effectiveness, and providing training programs for healthcare professionals, this study seeks to contribute to the global efforts in combating AMR and promoting prudent antibiotic use.

Prevalence of Uropathogenic E. Coli, Antimicrobial Susceptibility Profiles and Carriage of Extended-Spectrum Beta-Lactamases Genes at Mama Lucy Hospital, Kenya

Purpose: Urinary tract infection (UTI) is a common bacterial infection affecting millions worldwide. Escherichia coli (E. coli) is the most prevalent causative agent of UTIs. This study aimed to determine the prevalence, antimicrobial susceptibility profiles and carriage of ESβL resistance genes among uropathogenic E. coli recovered from adults at Mama Lucy Hospital. Methodology: A cross-sectional study was conducted. A purposive method was used to obtain 347 urine samples from patients who presented with symptoms suggestive of UTI and were cultured for E. coli using cysteine lactose electrolyte-deficient agar and eosin methylene blue agar. The collected urine samples were also subjected to dipstick analysis and microscopy. Questionnaires were used to collect sociodemographic data and possible risk factors for urinary tract infections. The recovered isolates were identified using conventional biochemical tests. Antimicrobial susceptibility profiles were determined using the Kirby diffusion disc method. The occurrence of ESβLs, including TEM, OXA, SHV, and CTX-M, was determined by polymerase chain reaction (PCR). Findings: The overall prevalence rate of UTIs was 23.7%, whereas the E. coli prevalence rate was 13.3%. The isolates presented high levels of resistance to trimethoprim-sulfamethoxazole (81.3%), amoxicillin-clavulanic acid (66.7%), ciprofloxacin (62.5%), tetracycline (60.4%), ceftriaxone (54.2%), and cefoxitin (54.2%), whereas they were more susceptible to meropenem (14.6%), chloramphenicol (12.5%), and nitrofurantoin (8.3%). A total of 25 of the 46 E. coli isolates were screened for ESβL genes. TEM was the most common gene21/25 (84%), SHV12/25 (48%), OXA 7/25 (28%), and CTX-M 18/25 (66.1%), which indicates a high frequency of β-lactamase gene production among UTIs causing E. coli. Unique Contribution to Theory, Practice and Policy: Based on these findings, current treatment guidelines should be revised to prevent increasing antimicrobial resistance through continuous surveillance, screening for extended-spectrum beta-lactamase genes, routine culture and antibiotic sensitivity testing. Additionally, the prevalence of UTIs should be continuously monitored to monitor trends that form a basis for preventive and treatment guidelines, such as policy development and prudent use of antibiotics, to reduce the increasing UTI burden in the population.

Mapping Antimicrobial Resistance in Staphylococcus epidermidis Isolates from Subclinical Mastitis in Danish Dairy Cows.

Background/Objectives: Although Staphylococcus epidermidis is a key cause of subclinical mastitis in Danish dairy cows, its sensitivity to antimicrobials remains unexplored. Here, we analyzed sixty S. epidermidis isolates derived from 42 dairy cows across six conventional dairy herds in Denmark. Methods: Phenotypic resistance was measured by antimicrobial susceptibility testing and minimum inhibitory concentration (MIC) analysis, and genotypic resistance was examined through whole-genome sequencing and identification of antimicrobial resistance genes (ARGs). Correspondence between phenotypic and genotypic resistance was then evaluated by Cohen's kappa statistics. Furthermore, the presence of plasmid replicon genes and the strain diversity among the S. epidermidis isolates was investigated to associate these findings with the observed AMR patterns. Results: Results showed that 30/60 isolates (50.0%) were resistant to penicillin phenotypically, while 35/60 (58.3%) were positive for a corresponding blaZ gene (κ = 0.83, p < 0.01). A fosB gene, encoding fosfomycin resistance, was detected in all 60/60 isolates (100.0%), but fosfomycin resistance was not analyzed phenotypically. Based on MIC analysis, 3/60 isolates (5.0%) were multi-drug resistant, showing resistance towards penicillin, erythromycin, and tetracycline. However, in 11/60 genomes (18.3%), ARGs encoding resistance towards ≥3 antimicrobial classes (e.g., beta-lactams, phosphonic acid, tetracyclines, aminoglycosides, macrolides, lincosamides, and fusidane) were detected. Eleven different ARGs were detected among the 60 isolates in total. No methicillin-resistant Staphylococcus epidermidis (MRSE) were recorded. Results further showed that each herd had one primary sequence type (ST) and resistance profile associated with it, and plasmid-mediated horizontal gene transfer of ARGs was indicated This study underscores the importance of routine resistance surveillance and species-specific diagnoses to improve treatment outcomes and ensure prudent use of antimicrobials.

Dissecting Commons as an Equalizer: Caste as a Case

ABSTRACT The debate on tragedy of commons in India attributes the decline of commons governance entwined with the system of caste and the promulgation of post-colonial land reforms as reasons for the privatization and decline of commons. The literature invigorates the caste system as a harbinger of the conservation of commons promoting the prudent use of natural resources. As against the argument that caste as a traditional method of governance ensured the conservation of resources and commons, we argue that the exclusionary practices of caste restricting the use and control of resources for a few while enabling exclusion from labouring castes were aimed not at conservation, rather functioned as an instrument of coercion and subjugation over the communities that are deprived of access. We also counterpose the perceptions of a non-privatized nature of commons in the pre-colonial mode of governance of commons by tracing the traits of the process of privatization with the pre-colonial institution of caste, further making a case for democratization of commons across castes.

The Changes in the Antibiotic Resistance of Staphylococcus aureus, Streptococcus pneumoniae, Enterococcus faecalis and Enterococcus faecium in the Clinical Isolates of a Multiprofile Hospital over 6 Years (2017-2022).

Background/Objectives: The growing resistance of bacteria to antibiotics is a serious problem in health care. The present study aims to assess the drug resistance of Staphylococcus aureus, Enterococcus faecium, Enterococcus faecalis and Streptococcus pneumoniae isolated from infections in a multispecialty hospital over a 6-year period. Methods: Identification and antimicrobial susceptibility testing were performed using the VITEK®2 automated system (Biomerieux). Results and Conclusions: Based on data from the analyzed hospital, MRSA strains were the etiological factor of 18-28% of S. aureus infections. In each year from 2017 to 2022, the percentage of MSSA strains steadily exceeded the number of MRSA strains. The MRSA strains isolated show significant sensitivity to antibiotic groups other than β-lactams, such as aminoglycosides, tetracyclines, cotrimoxazole, linezolid and vancomycin. Ciprofloxacin is the antibiotic to which S. aureus displays the second-highest resistance, after methicillin. In the case of MRSA strains, almost 100% lack of sensitivity to quinolines was found. An increase in the number of infections caused by strains of the Enterococcus genus was observed. For E. faecium strains, the percentage of vancomycin-resistant strains reached as much as 41% in 2018. Among the resistant strains in E. faecalis, VREs (Vancomycin-Resistant Enterococci) slightly predominate, while GREs (Glycopeptide-Resistant Enterococci) are much more prevalent in E. faecium. The data show that the percentage of S. pneumoniae strains insensitive to ampicillin ranged from 6% to 17%. In 2017, the percentage of strains resistant to this antibiotic reached 17%, while in 2022, their share decreased to 9%. In 2021-2022, the percentage of strains resistant to erythromycin was as high as 33%. This resistance is related to the MLS (macrolides, lincosamides, streptogramines B) mechanism. An increase in S. pneumoniae resistance to 100% was observed in 2017 and 2019. In the analyzed six-year period, from 2020 (beginning of the pandemic), in some groups of antibiotics, a significant increase in consumption in DDD/100 person-days was recorded. This is most visible in the case of fluoroquinolones. The analysis carried out will increase the effectiveness of empirical therapy in the hospital and the prudent use of antibiotics to limit the selection of multidrug-resistant strains.

The "best practices for farming" successfully contributed to decrease the antibiotic resistance gene abundances within dairy farms.

Farms are significant hotspots for the dissemination of antibiotic-resistant bacteria and genes (ARGs) into the environment and directly to humans. The prevalence of ARGs on farms underscores the need for effective strategies to reduce their spread. This study aimed to evaluate the impact of a guideline on "best practices for farming" aimed at reducing the dissemination of antibiotic resistance. A guideline focused on prudent antibiotic use, selective therapy, and hygienic and immune-prophylactic practices was developed and provided to the owners of 10 selected dairy farms and their veterinarians. Fecal samples were collected from lactating cows, dry cows, and calves both before and after the implementation of the guideline. ARGs (bla TEM, ermB, sul2, and tetA) were initially screened by end-point PCR, followed by quantification using digital droplet PCR. ARG abundance was expressed in relative terms by dividing the copy number of ARGs by the copy number of the 16S rRNA gene. The ARG abundances were higher in lactating cows compared to other categories. Despite similar levels of antibiotic administration (based on veterinary prescription data from the sampled farms) in both sampling campaigns, the total abundance of selected ARGs, particularly bla TEM and tetA, significantly decreased after the adoption of the farming guidelines. This study highlights the positive impact of prudent antibiotic use and the implementation of farming best practices in reducing the abundance of ARGs. The lactating cow category emerged as a crucial point of intervention for reducing the spread of antibiotic resistance. These findings contribute to ongoing efforts to address antibiotic resistance in farm environments and strengthen the evidence supporting the adoption of good farming practices.

Effect of capital structure on economic success of the DSE-listed firms in Bangladesh: A moderating role of COVID-19 pandemic

A firm's prudent use of debt and equity is an essential indicator of robust financial management. The study empirically evaluated the impact of capital structure (CS) on the economic performance of Bangladeshi companies from 2010 to 2022. It uses data from 1300 observations collected from 100 DSE-listed firms from 10 leading sectors of the economy. The outcome variables included ROE, ROA, EPS, and Q ratios. The explanatory variables were the capital structure proportions of short-term liabilities (STL), long-term liabilities (LTL), and the firm growth rate. The firm size was regarded as the control variable. The regression results revealed that STL negatively impacted ROA, ROE, and, most remarkably, EPS, while STL failed to impact Tobin's Q. LTL, on the other hand, had a positive impact on EPS and a negative impact on Tobin's Q, indicating that Bangladeshi firms do not exhibit overvaluation. STL and LTL positively impacted corporate financial performance during the pandemic compared to the pre-pandemic period. The implications of these findings are crucial for policymakers and corporate leaders. Organizations must demonstrate caution when employing short-term liabilities, especially during stable periods. This study underscores the imperative for industry-specific strategies concerning capital structure, as sectoral differences affect leverage outcomes.

Pain Medication Frequency and Fall Risk Among Community-Dwelling Older Adults With Arthritis.

Pain medication is commonly used among older adults with arthritis, elevating the risk of falling. We examined fall risks related to the frequency of taking pain medication among community-dwelling older adults with arthritis by analyzing a nationally representative sample of community-dwelling Medicare beneficiaries aged >65 with self-reported arthritis (n = 4,225) in the 2015 National Health and Aging Trends Study. The survey-weighted logistic regression revealed that after controlling for confounding factors, recent falls were associated with taking pain medication daily compared to never (OR = 1.45, 95% CI: 1.06, 1.96). The other categories of medication frequency, compared to never, were not associated with fall risk. Findings suggest that more prudent use of pain medication should be stressed by health care providers for older adults with arthritis to help reduce the risk of falls and fall injuries. Nonpharmacological pain management is encouraged to support active living among older adults with arthritis.

Pharmacokinetics and Pharmacodynamics Evaluation of Amoxicillin Against Staphylococcus pseudintermedius in Dogs.

Antibiotic resistance in bacteria from companion animals poses significant public health risks. Prudent antibiotic use, particularly through pharmacokinetics/pharmacodynamics modeling, is crucial for minimizing resistance. We investigated the pharmacokinetics/pharmacodynamics of amoxicillin (AMX) against Staphylococcus pseudintermedius. A pharmacokinetic study was conducted on healthy dogs subcutaneously injected with a dose of 15 mg/kg AMX. The antibacterial efficacy of AMX was evaluated against a standard strain from animals (KCTC 3344) and clinical isolates from dogs (B-2, B-7, and B-8), with minimum inhibitory concentrations (MICs) of 0.25, 0.5, 64, and 16 μg/mL, respectively. The half-life of AMX was 7 h, allowing for extended drug efficacy. The time above MIC (%T > MIC) values indicated that the AMX concentrations were maintained above MICs of the two susceptible strains (KCTC 3344 and B-2) for more than 80% of the time when dosed at a one-day interval, suggesting an effective treatment. The area under the curve over 24 h/MIC ratios confirmed the bacteriostatic, bactericidal, and bacterial eradication effects of AMX against S. pseudintermedius strains, except for B-7 (the most resistant strain). These results support improved clinical dosing strategies for AMX against S. pseudintermedius infections in dogs.

Economic Evaluation of Prudent Antibiotic Usage Campaigns: Enhancing Healthcare Quality and Reducing Costs

Background and Objective: Irrational use of antibiotics is a major cause of antibiotic resistance and increases healthcare costs. Promoting the prudent use of antibiotics in hospitals is an essential effort to improve the quality of antibiotic use among healthcare workers. This study aims to evaluate the quality and cost analysis of antibiotic use in surgical cases at RSND Semarang before and after the campaign for prudent antibiotic use. Methods: This study uses a quasi-experimental design with a one-group pre-test and post-test. The sample consisted of 86 patient medical records of surgical cases that met the inclusion and exclusion criteria at RSND. Data on the quality of antibiotic use were obtained from the medical records and analyzed by the RSND PPRA team using the Van Meer and Gyssens criteria. Data analysis was performed using the Chi-square test, and a cost analysis was conducted before and after the campaign for prudent antibiotic use. Results: The study found a significant difference in the quality and cost of antibiotic use in surgical cases at RSND Semarang before and after the campaign. Out of 44 medical records and 76 antibiotic prescriptions, the most frequently prescribed antibiotics were Ceftriaxone, Cefazolin, and Cefadroxil. The majority of antibiotics were categorized under Category V (no indication), accounting for 47.3%. The cost of antibiotic use in inappropriate categories (I-IV) was 1,003,630 IDR, while for Category V it was 497,606 IDR. The cost of appropriate antibiotic use (Category 0) was the lowest, at 332,653 IDR. Conclusion: The use of antibiotics without proper indication and inappropriately contributes the highest costs, with the most expensive being the inappropriate use of antibiotics. This highlights the importance of prudent antibiotic management to reduce unnecessary healthcare expenses and combat antibiotic resistance.

Quantification of Antimicrobial Use on Commercial Broiler Farms in Pakistan.

Pakistan has a large, intensive broiler production industry, where antimicrobials are extensively used for both therapeutic and prophylactic purposes. Monitoring antimicrobial use (AMU) at the farm level is crucial to guide interventions for antimicrobial stewardship. The objective of this study was to comprehensively quantify AMU on commercial broiler farms in Pakistan using different metrics. Data on on-farm AMU (both therapeutic and prophylactic) were collected from intensive commercial broiler farms in Punjab, Pakistan. AMU was quantified using four different metrics: treatment incidence (TI) based on defined daily dose (TIDDDvetPK), TI based on defined course dose (TIDCDvetPK), TI based on used daily dose (TIUDDvetPK), and mg/kg biomass. The median TIDDDvetPK, TIDCDvetPK, TIUDDvetPK, and mg/kg biomass values were 57.7 (7.5-257.9), 13.3 (1.8-52.5), 75.3 (21.1-182.9), and 301 (46.8-1009.6), respectively, based on 741 group treatments given at 100 participating farms with 225 flocks. About 34% treatments were administered for therapeutic purposes, with 66% administered as prophylaxis. A total of 41 active substances, distributed across 17 antimicrobial classes, were identified from 139 commercial antimicrobial products used. The most commonly used active substances (AS), out of total 741 group treatments, were colistin (polymyxins) at 17%, enrofloxacin (quinolones) at 8%, neomycin (aminoglycosides) and amoxicillin (aminopenicillins) at 7% each, and procaine penicillin (NS penicillins) and streptomycin (aminoglycosides) at 6% each. According to the WHO categorization, 57% of the used AS were found to be critically important antimicrobials (CIAs) for human medicine. As many as 30% of treatments were administered in the first week (13% on the first day of production), and the main indication was prophylaxis for early chick mortality, followed by 21% in week 5, with main indication being feed supplements for necrotic enteritis. The average weight at slaughtering was 2.25 kg, gained after an average of 44 days of the production cycle. The alarmingly high AMU in Pakistani broiler production emphasizes the urgent need to reduce AMU, particularly involving CIAs and the prophylactic use of antimicrobials. This can be achieved by improving farm management practices and strengthening regulatory oversight to enable prudent antimicrobial use, eventually reducing the risk of AMR.

Future Challenge: Assessing the Antibiotic Susceptibility Patterns of Staphylococcus Species Isolated from Canine Otitis Externa Cases in Western Romania.

Antimicrobial resistance (AMR) has surfaced as a critical challenge to public health on a global scale. The precise and swift identification of resistance to antimicrobial agents, along with timely and suitable antimicrobial therapy paired with effective stewardship practices, is crucial for managing the rise and dissemination of antimicrobial resistance. The objective of our investigation was to outline the antimicrobial resistance profile of Staphylococcus spp., a significant contributor to canine otitis, a prevalent condition in dogs, isolated in Western Romania. All data were collected from clinical cases of canine otitis externa which presented at the University Clinic of the Faculty of Veterinary Medicine in Timișoara/Romania. A clinical evaluation was conducted, from which era swabs are usually collected and sent for analysis at the laboratory. Laboratory analysis included the microbiological examination for identifying Staphylococcus spp. and determining antibiotic susceptibility phenotypes. Statistical analysis was implemented on all data that were collected. The ear swabs were processed with standard procedures for cultivating and identifying bacteria. The resulting subcultures were processed to determine the staphylococcal species on the GP ID Cards of the Vitek® 2 automatic system. The antimicrobial susceptibility profiles were detected by the Vitek® 2 system using an AST-GP80 card. These isolated Staphylococcus spp. strains were further processed by real-time PCR and PCR-RFLP. Of all the auricular exudate samples analyzed, 76 were positive for Staphylococcus spp. (59.38%). Within these, in 82% of auricular samples, six distinct Staphylococcus spp. were identified (Staphylococcus (S.) pseudintermedius, S. intermedius, S. hyicus, S. delphiny, S. shleiferi, and S. aureus). Our data indicate that the PCR-RFLP assay is a practical approach to S. pseudintermedius identification, allowing for discrimination from the other Staphylococcus Intermedius Group (SIG) species and important staphylococcal pathogens of dogs. The highest frequency of resistant S. pseudintermedius isolates was detected against tetracycline (21/34; 61.76%; p-value 0.003), gentamicin (20/34; 58.82%), and kanamycin (20/34; 58.82%). These results are essential to guide the prudent use of antibiotics in veterinary medicine. They will also help design efficient control strategies and measure their effectiveness.

Does Frequent Use of Advanced Energy Devices Improve Hysterectomy Outcomes?

Background and Objectives: The objective of this study was to assess the efficient use of advanced energy devices by examining the impact of their usage frequency on surgical outcomes of total laparoscopic hysterectomies. Materials and Methods: A retrospective study was conducted between 2020 and 2023 by a single surgeon. The patients' medical records and surgical videos were reviewed. Cases were categorized into three groups based on the frequency of usage of advanced energy devices: Group 1 (≤10 uses), Group 2 (11-20 uses), and Group 3 (≥21 uses). The differences in blood loss, surgery time, and surgical outcomes among these groups were analyzed. This study was conducted as a single-center retrospective analysis. It included 126 patients who underwent total laparoscopic hysterectomy and provided informed consent for video recording. To evaluate the usage of advanced energy devices, anonymized surgical videos were reviewed, and outcomes were analyzed based on the frequency of usage of advanced energy devices. Results: The time required for surgery differed significantly among the three groups (p = 0.006). However, no significant differences were observed in the changes in hemoglobin levels or estimated blood loss (p = 0.255 and 0.053, respectively). Additionally, the application of hemostatic agents, the need for intraoperative or postoperative transfusions, and the use of intravenous hemostatic agents postoperatively showed no notable variation. Complication rates, including rates of hematoma, urinary tract injury, gastrointestinal injury, and infections necessitating reoperation, were also comparable. Conclusions: The findings suggest that the prudent and strategic use of advanced energy devices, rather than their frequent application, may improve surgical efficiency without increasing the risk of complications.

Co-selection of antibiotic and disinfectant resistance in environmental bacteria: Health implications and mitigation strategies.

The rapid emergence of co-selection between antimicrobials, including antibiotics and disinfectants, presents a significant challenge to healthcare systems. This phenomenon exacerbates contamination risks and limits the effectiveness of strategies to combat antibiotic resistance in clinical settings. This study aimed to investigate the prevalence and characteristics of bacteria in hospital environments that exhibit co-selection mechanisms and their potential implications for patient health, framed within the One Health perspective. Air and surface samples were collected from seven large hospitals and analyzed to detect antibiotic-resistant bacteria (ARB). The resistance profiles of isolated ARB to various disinfectants were determined. Bacterial species were identified using 16S rRNA gene sequencing, and the presence of antibiotic resistance genes (ARGs) and class 1 integrons (intI1) was investigated. A high percentage (85%) of samples contained ARB, with β-lactam resistance being the most frequently observed. Alarmingly, 94% of isolated ARB exhibited resistance to at least one disinfectant, and 91% demonstrated resistance to three or more disinfectants. Staphylococcus and Bacillus emerged as the dominant genera displaying co-selection. The presence of ARGs, including mecA (associated with methicillin resistance) and qacB (associated with disinfectant resistance), along with intI1, provided further evidence supporting co-selection mechanisms. These findings underscore the critical need for robust antimicrobial resistance surveillance and the prudent use of disinfectants in healthcare settings. Further research into co-selection mechanisms is essential to inform the development of effective infection control strategies and minimize the spread of resistant bacteria.

One hundred years of success in antimicrobials: but what will the next 100 years bring?

In the past 100 years, thanks to the discovery and development of antimicrobial therapies, human and veterinary medicine have made a leap forward in treating infectious diseases. However, resistance mechanisms quickly appeared and spread in all sectors - human, animal and environmental - throughout the world, thus jeopardising the progress made. Awareness has been raised only gradually but is now prominent at the global level, due in large part to the action of international organisations such as the World Organisation for Animal Health (WOAH), the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO), and antimicrobials are considered a global public health good to be preserved. Under the leadership of WOAH in particular, the actions undertaken in research, surveillance, information, training, awareness and communication are moving in the right direction towards responsible and prudent use of antimicrobials. In the next 100 years, the fight against antimicrobial resistance will undeniably remain a crucial challenge for public health, veterinary public health and agriculture. Concerted efforts and scientific innovations, such as in functional genomics and artificial intelligence, could offer solutions to mitigate the impact of this growing threat. A multidisciplinary and comprehensive One Health approach is necessary to successfully address antimicrobial resistance. International collaboration remains crucial, and international organisations such as WOAH, WHO, FAO and the United Nations Environment Programme must continue their essential role in coordinating these efforts.

INVITED REVIEW: Antimicrobial Resistance Genes in Milk: a 10-year-systematic review and critical comment.

The occurrence of antimicrobial resistance genes in milk is eagerly discussed as a public health risk, and frequently investigated. Here, we perform a systematic review on the abundance of antimicrobial resistance genes in milk from primary production over a 10-year-period. We aimed to provide a comprehensive data set on known and emerging antimicrobial resistance genes in major mastitis pathogens, occurring worldwide in milk at primary production, and to critically discuss the relevance and constraints of these findings. We searched Pubmed for peer-reviewed studies published between 2012 and 2022 that fit fixed combinations of keywords and did not meet exclusion criteria such as "mixed with other sources." For synthesis, data on occurrence was extracted from studies and supplements. To address plausibility issues, we performed an NCBI BLAST search. Results & limitations. Our search revealed 2222 publications in total. Of them, 500 studies were eligible for full-text reads and 306 publications were included in data compilation. An overwhelming majority of studies dealt with mecA in Staphylococcus aureus, followed by extended-spectrum β-lactamase-encoding genes such as blaCTXM in Escherichia coli, while other mastitis pathogens such as Streptococcus spp. were scarcely investigated. In most cases, < 5% of milk samples were positive for major pathogens bearing the antimicrobial resistance gene of interest. However, huge study-to-study differences were found between regions, but also on a national level. For instance, the estimate prevalence of Escherichia coli-borne blaCTXM in mastitis milk samples ranged from 0.0% to 55%, with a median value of 8.02%, while in healthy individuals and bulk milk, the prevalence ranged from 0.0% to 20.0%, with a median value of 0.8%. Several studies reported antimicrobial resistance genes for the very first time in a species, but did not stand up to scrutiny. As an example, frequent detection of TEM-genes in streptococci is most likely attributed to contamination of molecular reagents, as reported elsewhere. Despite the huge amount of data, there is a need for more quality control, more representative sampling of milk, more quantitative research, and deeper insights into bacterial genomics, to identify relevant and/or emerging antimicrobial resistance genes in milk. Considering a low percentage of contaminated milk samples, unknown ARG-concentrations and an unproven role in human disease, the risk attributed to ARGs in milk seems to be exaggerated by far. However, the risk of ARG-selection on farm, resulting in low treatment success in cattle, is a real one and should be met by prudent use of antibiotics.

Prudent use and antimicrobial prescription practices in Ethiopian veterinary clinics located in different agroecological areas

BackgroundUnderstanding antimicrobial prescribing (AMP) practices and their prudent use in livestock can support the implementation of stewardship programs in veterinary medicine. Empiric therapy using antimicrobials is widely practiced in resource-poor settings, including Ethiopia. This could significantly contribute to the global burden of antimicrobial resistance (AMR) and the potential accumulation of residues in food. This study assessed AMP practices in Ethiopian veterinary clinics located in different agroecological zones (AEZs) as well as adherence to antimicrobial stewardship principles (ASPs).MethodsData were collected from case book records from four district veterinary clinics located in different AEZs in Ethiopia from 2015 to 2019. To identify factors associated with non-prudent AMP practices (i.e., the use of antimicrobials without therapeutic effects or benefits to the animal), data from registered clinical veterinary cases were selected using a systematic random sampling method. This led to the inclusion of approximately one-third of all records, including animal characteristics, disease symptoms and diagnosis, and details about the prescribed drugs. Descriptive statistics were used to report the proportions of drugs prescribed and adherence to the ASPs. The Chi-square test was used to establish an association between the drugs prescribed and the disease diagnoses and the districts. The factors associated with cases receiving antimicrobials and non-prudent AMP practices were also assessed using a multivariable logistic regression analysis.ResultsIn total, 12,438 clinical case records were considered. Approximately 97% of these cases received treatment without laboratory confirmation, and 15,243 drugs were prescribed. Among these prescriptions, 75% were for antimicrobials, with oxytetracycline (29%) and a combined formulation of penicillin-dihydrostreptomycin (19%) being the most often prescribed drugs. Overall, 19% of the cases were treated non-prudently with antimicrobials, with high incidences at Holeta (32%) and Sekoru (19%) (p < 0.001). Most cases, including viruses and other non-pathogens (100%), toxicants (97%), unknown causes (94%), fungi (70%), nutritional (64%), risk of bacterial infection (42%), and endo-ectoparasites (24%), were treated non-prudently. Cases receiving antimicrobials and non-prudent AMP were associated with Holeta and Sekoru study clinics, major clinical signs of bloat and loss of body condition, and illness due to viral infections (p < 0.05). Conversely, species of animals and cases diagnosed with multiple etiologic agents and respiratory diseases were negatively associated with prudent AMP practices (p < 0.05).ConclusionsMuch of the prescription practice observed in this study did not adhere to the ASPs; there were significant discrepancies between the prescribed drugs and disease diagnoses. Prescribing antimicrobials for unrelated diagnoses may contribute to an increase in AMR. The study thus underlines the need for mechanisms to improve accurate disease diagnosis and prescriber adherence to prudent AMP in countries with limited resources.

Epidemiology and Molecular Characterisation of Multidrug-Resistant Escherichia coli Isolated from Cow Milk.

Antimicrobial resistance (AMR) is a growing global concern and poses a significant threat to public health. The emergence of multidrug-resistant organisms, including Escherichia coli, also presents a risk of transmission to humans through the food chain, including milk. This study aimed to investigate the prevalence of E. coli in raw milk in the Chattogram metropolitan area (CMA) of Bangladesh and their phenotypic and genotypic antimicrobial resistance patterns. A total of 450 raw cow milk samples were collected from 18 farms within the CMA. The isolation and identification of E. coli were performed following standard bacteriological methods. Antimicrobial susceptibility testing (AST) was conducted using the Kirby-Bauer disc diffusion method. Molecular detection of E. coli and antimicrobial resistance genes was performed using the Polymerase Chain Reaction (PCR). This study found 134 (29.77%) milk samples that tested positive for E. coli. Antimicrobial susceptibility testing (AST) revealed the highest resistance rates (69.40%) to be for ampicillin, amoxicillin-clavulanic acid, cephalothin, and cephalexin, with the lowest resistance (21.64%) being for norfloxacin. A significant correlation (r = 1) was observed between ciprofloxacin and ceftazidime resistance among the antimicrobials tested. All E. coli isolates were classified as multidrug-resistant (MDR), being resistant to three or more antimicrobial classes, with a multiple resistance index >0.2. PCR amplification showed that the blaTEM gene had the highest prevalence (74.19%) among the ESBL and antimicrobial resistance genes tested. In contrast, the blaCMY-1 gene had a lower prevalence (6.45%) among the ESBL genes, while the tetD gene had the lowest prevalence (2.9%) among the resistance genes tested. Positive correlations were observed between antimicrobial resistance and the presence of these resistance genes. This study emphasises the high prevalence of MDR E. coli in raw cow milk and its significant potential impact on public health. It underscores the urgent need for strategic interventions to effectively manage and mitigate AMR in the Bangladeshi dairy sector, focusing on the prudent use of antimicrobials and implementing enhanced AMR surveillance.

Serovars, virulence factors, and antimicrobial resistance profile of non-typhoidal Salmonella in the human-dairy interface in Northwest Ethiopia: A one health approach.

Non-typhoidal Salmonella (NTS) is a zoonotic pathogen that exerts huge public health and economic impacts in the world. The severity of illness is mainly related to the serovars involved, the presence of virulence genes, and antimicrobial resistance (AMR) patterns. However, data are scarce on serovars, virulence genes, and AMR among NTS identified from the human-dairy interface in Northwest Ethiopia. Thus, this study investigated the serovars, common virulence genes, and AMR patterns of NTS isolates in the area. The study was conducted from June 2022 to August 2023 among randomly selected 58 dairy farms. A total of 362 samples were processed to detect NTS using standard bacteriological methods. The presumptive positive colonies were confirmed by Matrix-Assisted Laser Desorption Ionization-Time-of-Flight (MALDi-ToF). Polymerase chain reaction (PCR) was used to detect virulence genes, including invA and spvC. A slide agglutination test according to the White-Kauffmann-Le Minor scheme was employed to identify the serovars of the NTS isolates. The Kirby-Bauer disk diffusion method was used to assess the antimicrobial susceptibility patterns. Of the processed samples (362), 28 (7.7%) NTS isolates were detected. When distributed among samples, the proportions were 11.9%, 10.5%, 10.3%, 5.2%, 4.3%, and 1.7% among cows' feces, dairy farm sewage, pooled raw milk, milk container swabs, milkers' stool, and milkers' hand swab samples, respectively. Six serovars were detected with the dominancy of S. Uganda (39.3%), followed by S. enterica subsp. diarizonae (25.0%) and S. Typhimurium (21.4%). Among the 28 NTS isolates, 100% and 21.4% had the virulence genes invA and spvC, respectively. The susceptibility profile showed that 89.3% of the NTS isolates were resistant to at least one antimicrobial agent and 46.4% were resistant to three or more classes of antimicrobials (multidrug-resistant). Among antimicrobials, isolates were highly resistant to ampicillin (57.1%), followed by tetracycline (42.9%) and chloramphenicol (35.7%). On the other hand, the NTS isolates were 100%, 96.4%, and 96.4% susceptible to ceftriaxone, azithromycin, and norfloxacin, respectively. In conclusion, we detected NTS from humans, dairy cows, raw milk, dairy utensils, and the environment (sewage), showing the potential of the human-dairy farm-environment nexus in the NTS circulation. These further highlight that the interface is a good point of intervention in the control and prevention of NTS infection. The susceptibility profiles of the isolate necessitate interventions including the prudent use of the antimicrobials.