Humans, Animals, Food and Environment: One Health Approach against Global Antimicrobial Resistance

Screening canine sources for novel antimicrobials reveals the circular broad-spectrum bacteriocin, caledonicin, produced by Staphylococcus caledonicus

Introduction

Antimicrobial-resistant pathogens present an ongoing threat to human and animal health, with deaths linked to antimicrobial resistance (AMR) predicted to increase annually. While the misuse and overuse of antibiotics in humans undoubtedly contribute to this escalation, antibiotic use in the veterinary field, including companion animals, also plays a contributing role. Pet owners' desire to improve the quality of life of their pets is likely to support antibiotic use in this field. Consequently, there is a need for antibiotic alternatives to treat bacterial infections. This study set out to screen for antimicrobial peptides known as bacteriocins from bacterial isolates of aerobic/microaerophilic environments of canine sources and determine their potential as antibiotic alternatives against clinically relevant pathogens.

Methods

Following a laboratory-based protocol, 22 bacterial isolates were subjected to whole-genome sequencing (WGS), and a total of 14 putative novel bacteriocins were identified from both class I and II bacteriocin classes. One particular bacteriocin, herein named caledonicin, was identified via in silico analysis from a Staphylococcus caledonicus strain and partially purified for further in vitro evaluation.

Results

Caledonicin is a 64-amino acid (IAANLGVSSGTAYS MANALNNISNVATA LTIIGTFTGVGTIGSGIA ATILAILKKKGVAAAAAF) novel circular bacteriocin most closely related to enterocin_NKR-5-3B based on core peptide alignment (39.1%), with a molecular weight of 6077.1 Da. Caledonicin exhibits a broad-spectrum of activity against a range of pathogenic bacteria, including methicillin-resistant Staphylococcus aureus (MRSA), methicillin-resistant Staphylococcus pseudintermedius (MRSP), and Listeria monocytogenes; and the gut-related bacterium associated with Crohn's disease, Mediterraneibacter gnavus ATCC 29149 (previously Ruminococcus gnavus ATCC 29149).

Discussion

This represents the first bacteriocin screening study involving bacteria from canine sources and confirms this is a rich environment for bacteriocin-producing strains. This study also identifies and characterises the first novel bacteriocin from the staphylococcal species, Staphylococcus caledonicus.

Farmers' knowledge in the Swiss canton Valais: cultural heritage with future significance for European veterinary medicine?

BACKGROUND

The demand for natural product-based treatment options for livestock is increasing by animals' owners, veterinarians and policy makers. But at the same time, the traditional knowledge about it is at risk of falling into oblivion in Europe. The present study recorded this knowledge for the linguistically and geographically interesting Swiss canton of Valais.

METHOD

Open, semi-structured interviews were used to collect detailed information on formulations and applications, including plant species and natural substances, origin of material, extraction and preparation of herbal products, indication and type of application, dosage, sources of knowledge, frequency of usage and self-assessment of the treatment.

RESULTS AND DISCUSSION

In the course of 43 interviews, 173 homemade single species herbal remedy report (HSHR) were recorded. They included 53 plant species from 30 botanical families. Plant species from the botanical families of Asteraceae, Rubiaceae and Cupressaceae were mentioned the most, while the most frequently documented plant species were Coffea arabica L., Juniperus sabina L., Arnica montana L. and Matricaria chamomilla L. For the 173 HSHR, a total of 215 uses were mentioned, most of which were for the treatment of gastrointestinal and metabolic disorders, followed by skin lesions and genito-urinary tract problems. Regional peculiarities emerged, such as the use of Leontopodium alpinum Cass. for diarrhea in the French-speaking Valais, while Matricaria chamomilla and Camellia sinensis L. were used in the German-speaking part instead. In comparison with other regions of Switzerland, 10 plants were reported for the first time, including Juniperus sabina with 18 use reports.

CONCLUSION

The daily use on farms and the high satisfaction of farmers with homemade herbal remedies demonstrate their high practical relevance. In conclusion, the traditional regional knowledge about the use of medicinal plants is not only a cultural heritage worth protecting, but also an essential resource for the further development of European veterinary medicine.

Addressing antimicrobial resistance in low and middle-income countries: overcoming challenges and implementing effective strategies

Antimicrobial resistance (AMR) has become a critical worldwide health crisis. It poses major challenges for healthcare systems across the globe, demanding immediate attention and action. Low and middle-income countries (LMICs), in particular, encounter unique obstacles in addressing AMR due to various factors. This article aims to examine specific challenges and propose effective strategies to combat this issue. Through a comprehensive review of existing literature, this article identifies common barriers and successful interventions in tackling AMR. The research highlights several challenges faced by LMICs in addressing AMR, including limited access to quality healthcare services, socioeconomic disparities, limited awareness, inadequate surveillance systems and data collection, limited regulatory frameworks and quality control, as well as weak healthcare infrastructure and infection prevention practices. The research suggests strategies like improving healthcare access, promoting responsible antimicrobial use, enhancing surveillance, ensuring quality antimicrobial drugs, and fostering global collaboration to address these challenges. By understanding the challenges encountered by LMICs, it is possible to mitigate the impact of AMR and contribute to global efforts in combating this growing threat.

Antibiotics as Adjunctive Therapy in the Non-Surgical Treatment of Peri-Implantitis: A Systematic Review and Meta-Analysis

The role of antibiotics as adjunctive therapy in the non-surgical treatment of peri-implantitis is uncertain. The aim of this systematic review of randomized controlled trials was to assess the efficacy of antibiotic therapy, local or systemic, as an adjunctive to the non-surgical therapy of peri-implantitis. Primary outcomes were: implant success rate and complications, changes in radiographic bone level, probing pocket depth (PPD), probing attachment level (PAL), bleeding on probing (BOP) and peri-implantitis resolution. Six studies were included: two using topical and four systemic antibiotics. Adjunctive local antibiotics improved PPD (mean difference (MD) = 0.6 mm; 95% CI 0.42-0.78), BOP (MD = 0.15% (95% CI 0.10, 0.19)) and the success rate (risk ratio = 9.89; 95% CI 2.39-40.84). No significant difference in bone level and success rate were found with the use of systemic antibiotics, although they appeared to improve PPD (MD = 1.15 mm; 95% CI 0.31-1.99) and PAL (MD = 1.10 mm; 95% CI 0.13-2.08). Within the limitations of this review, the adjunctive local antibiotics showed improved outcomes in terms of success rate, PPD and BOP, while adjunctive systemic antibiotics improved PPD and PAL only. Peri-implantitis resolution was about 20-30% using adjunctive local antibiotics, whilst it ranged from 2% to 65% with adjunctive systemic antibiotics. Findings are still controversial, since they are based on few studies with high heterogeneity, at the uncertain or high risk of bias and involve few patients. Non-surgical debridement and maintenance periodontal support therapy remain pivotal and the adjunctive use of antibiotics for peri-implantitis cannot be routinely recommended, even considering the increasing concern on antibiotic resistance.

Essential Oil-Based Nanoparticles as Antimicrobial Agents in the Food Industry

The use of essential oils (EO) loaded with nanoparticles is the most promising alternative to increase food quality and safety. Interesting works describe the antimicrobial properties of EO for pathogen control in natural and processed foods for human health and animal production, also contributing to sustainability. Their association with different nanosystems allows novel developments in the micronutrition, health promotion, and pathogen control fields, preventing the aggravation of bacterial microevolution and combating antibiotic resistance. Benefits to the environment are also provided, as they are biodegradable and biocompatible. However, such compounds have some physicochemical properties that prevent commercial use. This review focuses on recent developments in antimicrobial EO-based nanoparticles and their application in different food matrices.

Detection of Antimicrobial Resistance, Pathogenicity, and Virulence Potentials of Non-Typhoidal Salmonella Isolates at the Yaounde Abattoir Using Whole-Genome Sequencing Technique

One of the crucial public health problems today is the emerging and re-emerging of multidrug-resistant (MDR) bacteria coupled with a decline in the development of new antimicrobials. Non-typhoidal Salmonella (NTS) is classified among the MDR pathogens of international concern. To predict their MDR potentials, 23 assembled genomes of NTS from live cattle (n = 1), beef carcass (n = 19), butchers’ hands (n = 1) and beef processing environments (n = 2) isolated from 830 wet swabs at the Yaounde abattoir between December 2014 and November 2015 were explored using whole-genome sequencing. Phenotypically, while 22% (n = 5) of Salmonella isolates were streptomycin-resistant, 13% (n = 3) were MDR. Genotypically, all the Salmonella isolates possessed high MDR potentials against several classes of antibiotics including critically important drugs (carbapenems, third-generation cephalosporin and fluoroquinolone). Moreover, >31% of NTS exhibited resistance potentials to polymyxin, considered as the last resort drug. Additionally, ≤80% of isolates harbored “silent resistant genes” as a potential reservoir of drug resistance. Our isolates showed a high degree of pathogenicity and possessed key virulence factors to establish infection even in humans. Whole-genome sequencing unveiled both broader antimicrobial resistance (AMR) profiles and inference of pathogen characteristics. This study calls for the prudent use of antibiotics and constant monitoring of AMR of NTS.

Monitoring antibiotic resistance genes in wastewater environments: The challenges of filling a gap in the One-Health cycle

Antibiotic resistance (AR) is a global problem requiring international cooperation and coordinated action. Global monitoring must rely on methods available and comparable across nations to quantify AR occurrence and identify sources and reservoirs, as well as paths of AR dissemination. Numerous analytical tools that are gaining relevance in microbiology, have the potential to be applied to AR research. This review summarizes the state of the art of AR monitoring methods, considering distinct needs, objectives and available resources. Based on the overview of distinct approaches that are used or can be adapted to monitor AR, it is discussed the potential to establish reliable and useful monitoring schemes that can be implemented in distinct contexts. This discussion places the environmental monitoring within the One-Health approach, where two types of risk, dissemination across distinct environmental compartments, and transmission to humans, must be considered. The plethora of methodological approaches to monitor AR and the variable features of the monitored sites challenge the capacity of the scientific community and policy makers to reach a common understanding. However, the dialogue between different methods and the production of action-oriented data is a priority. The review aims to warm up this discussion.

Multi-Drug and β-Lactam Resistance in Escherichia coli and Food-Borne Pathogens from Animals and Food in Portugal, 2014–2019

Animal and food sources are seen as a potential transmission pathway of antimicrobial resistance (AMR) to humans. The aim of this study is to describe Campylobacter, Salmonella, and commensal Escherichia coli multi-drug resistance (MDR) in the food chain between 2014 and 2019 in Portugal. AMR surveillance data from food-producing animals and food were assessed. MDR relative frequencies were estimated by bacterial genus and year. AMR profiles were created using observations of resistance to antimicrobial classes from each isolate. Antimicrobial susceptibility testing results were clustered using k-modes. Clusters were described by population, AMR classification, β-lactamases, sample stage, sample type, season, and year. Overall, MDR was more prevalent for E. coli, ranging from 74–90% in animal and 94–100% in food samples. MDR was found to be more widespread in resistance profiles that were common among E. coli and Salmonella isolates and in those exclusively observed for E. coli, frequently including (fluoro)quinolones and cephalosporins resistance. β-lactam resistance was observed around 75% to 3rd/4th-generation cephalosporins in E. coli. Clusters suggest an escalating MDR behaviour from farm to post-farm stages in all bacteria and that Salmonella (fluoro)quinolones resistance may be associated with broilers. These findings support policy and decision making to tackle MDR in farm and post-farm stages.