Antimicrobial resistance: one world, one fight!

Toxicological assessment of citral and geraniol: Efflux pump inhibition in Staphylococcus aureus and invertebrate toxicity

This study aimed to evaluate the antibacterial activity against multi-drug-resistant strains carrying efflux pumps and assess their toxicity on Drosophila melanogaster and Aedes aegypti models. Microdilution tests in broth were performed to determine the Minimum Inhibitory Concentration (MIC). The efflux pump inhibition was evaluated by analyzing the reduction in antibiotic MIC and Ethidium Bromide (EtBr) MIC when combined with the products. Mortality assay and negative geotaxis were conducted on D. melanogaster specimens, and insecticidal activity assays were performed on A. aegypti larvae. Only geraniol reduced the antibiotic MIC when combined, reducing from 64 µg/mL to 16 µg/mL in the 1199B strain of S. aureus. When combined with EtBr, both geraniol and citral reduced EtBr MIC, with geraniol decreasing from 64 µg/mL to 16 µg/mL and citral decreasing from 64 µg/mL to 32 µg/mL. Regarding the S. aureus K2068 strain, geraniol reduced the antibiotic MIC from 16 µg/mL to 8 µg/mL, and citral reduced it from 16 µg/mL to 4 µg/mL. In combination with EtBr, all monoterpenes reduced MIC from 64 µg/mL to 32 µg/mL. Both products exhibited toxicity in D. melanogaster; however, citral showed higher toxicity with a precisely determined LC50 of 2.478 μL. As for the insecticidal action on A. aegypti, both products demonstrated toxicity with cumulative effects and dose-dependent mortality.

Genomic characterization of antimicrobial-resistance and virulence factors in Salmonella isolates obtained from pig farms in Antioquia, Colombia

BACKGROUND

Occurrence of antimicrobial-resistant Salmonella strains has been reported worldwide, because of inappropriate use of antimicrobial products in either humans or animals. The presence of multidrug resistant Salmonella in pig production systems had been reported in Antioquia, Colombia.

AIM

To identify antimicrobial resistance genes (ARG) in different Salmonella spp. strains isolated from pig productions in Antioquia, Colombia. Methods: Samples were received at the Diagnostic Unit of the Faculty of Agrarian Sciences at the University of Antioquia, from January 1, 2019, to January 2021. A total of 28 isolates of Salmonella spp. were included, which presented phenotypic resistance to more than one antibiotic used in pig farms. Whole genome sequencing (WGS) was performed in the Unit of Genomic of Agrosavia using an automated pipeline from the GHRU- Sanger Institute, employing the Illumina MiSeq platform.

RESULTS

WGS revealed 34 ARGs among these isolates. In 25 isolates (89%) more than two ARGs were found. Genes encoding resistance were found for 10 different groups of antibiotics (beta-lactam, aminoglycosides, chloramphenicol, rifampicins, lincosamides, fluoroquinolones, tetracyclines, sulfonamides and trimethoprim). The most frequently observed MDR profile in Typhimurium isolates was AMP-CEX-CEP-CEF-EFT-CEQ-FLU-ENR-TE-FFC-SXT.

CONCLUSION

The presence of multi-drug resistant Salmonella strains in pigs destined for human consumption in Antioquia, Colombia was determined. This research emphasizes the utmost importance of epidemiological tools to understand the presence and spreading of antimicrobial resistance genes in pig farms. Additionally, it highlights the critical need for developing educational programs and public policies to help reduce the spread of antimicrobial resistance in production systems.

Effect of Exogenous Glucose on Molecular Transport through Bacterial Membranes Studied by Second Harmonic Light Scattering

Recent studies revealed that exogenous glucose increases the efficacy of aminoglycosides in eliminating bacterial persister cells. It was speculated that this increased antimicrobial efficacy is induced by glucose-facilitated uptake of the antibiotics. Here, we examine this hypothesis by using second-harmonic light scattering to time-resolve the transport of an antimicrobial quaternary ammonium compound (QAC), malachite green, across the membranes of living Escherichia coli (E. coli) in the presence of glucose. The results show that when the glucose concentration increased from 0 to 100 μM, the QAC transport rate constant across the cytoplasmic membrane of E. coli increased by 3.6 times. Further increase of glucose concentration into the millimolar range, however, does not further enhance the transport rate constant. Conversely, a study of QAC transport across the protein-free membrane of liposomes (constructed from the polar lipid extract of E. coli) indicates that the glucose-induced enhancement in membrane transport in E. coli is mediated by protein transporters. Cell viability experiments show that low concentration of exogenous glucose enhances the QAC efficacy in eliminating E. coli. The loss of viability of the bacterial cells in the presence of the QAC at minimum inhibitory concentration increased dramatically when glucose concentration increased from 0 to 100 μM but increasing the glucose concentration up to 1 mM did not further enhance the antimicrobial efficacy. This behavior coincides with the observed increase in QAC transport rate constant as a function of glucose concentration. These observations reveal a novel antimicrobial strategy in which low concentration glucose enhances the uptake of antimicrobials into the bacteria, thereby improving antimicrobial efficacy.

Antimicrobial Resistance in the Context of Animal Production and Meat Products in Poland-A Critical Review and Future Perspective

The prevalence of antimicrobial-resistant bacteria in meat and meat products is a significant public health challenge, largely driven by the excessive and inappropriate use of antimicrobials in animal husbandry. In Poland, a key meat producer in Europe, antibiotic-resistant pathogens such as Campylobacter spp., Staphylococcus spp., Enterococcus spp., Listeria monocytogenes, and Enterobacterales have been detected in meat, posing serious risks to consumers. This review examines the use of antimicrobial agents in meat production and the resulting antimicrobial resistance (AMR) in microorganisms isolated from meat products in Poland. The mechanisms of AMR, genetic factors, and prevalence in Poland are presented. It highlights key factors contributing to AMR, such as antibiotic misuse in livestock farming, and discusses the legal regulations governing veterinary drug residues in food. This review emphasizes the importance of monitoring and enforcement to safeguard public health and calls for further research on AMR in the meat industry. Antimicrobial resistance in meat and meat products in Poland is a huge challenge, requiring stricter antibiotic controls in animal husbandry and improved surveillance systems. Additionally, the impact of husbandry practices on the environment and food requires further research. Future efforts should focus on nationwide monitoring, alternative strategies to reduce antibiotic use, and stronger enforcement to combat antimicrobial resistance and protect public health.

The Synergy between Antibiotics and the Nanoparticle-Based Photodynamic Effect

Antimicrobial resistance (AMR) is a growing global health concern, necessitating innovative strategies beyond the development of new antibiotics. Here, we employed NdYVO4:Eu3+ nanoparticles, which can persistently produce reactive oxygen species (ROS) after stopping the light, as a model of photodynamic nanoparticles and demonstrated that the photodynamic effect can serve as an adjuvant with antibiotics to effectively reduce their minimum inhibitory concentration. These preirradiated nanoparticles could penetrate the bacterial cell membrane, significantly enhancing the potency of antibiotics. We showed that the synergy effect could be attributed to disrupting crucial cellular processes by ROS, including damaging cell membrane proteins, interfering with energy supply, and inhibiting antibiotic metabolism. Our findings suggested that complementing the photodynamic effect might be a robust strategy to enhance antibiotic potency, providing an alternative antibacterial treatment paradigm.

Antibiotic use and adherence to the WHO AWaRe guidelines across 16 hospitals in Zambia: a point prevalence survey

Background

The inappropriate use of antibiotics in hospitals contributes to the development and spread of antimicrobial resistance (AMR). This study evaluated the prevalence of antibiotic use and adherence to the World Health Organization (WHO) Access, Watch and Reserve (AWaRe) classification of antibiotics across 16 hospitals in Zambia.

Methods

A descriptive, cross-sectional study employing the WHO Point Prevalence Survey (PPS) methodology and WHO AWaRe classification of antibiotics was conducted among inpatients across 16 hospitals in December 2023, Zambia. Data analysis was performed using STATA version 17.0.

Results

Of the 1296 inpatients surveyed in the 16 hospitals, 56% were female, and 54% were aged between 16 and 50 years. The overall prevalence of antibiotic use was 70%. Additionally, 52% of the inpatients received Watch group antibiotics, with ceftriaxone being the most prescribed antibiotic. Slightly below half (48%) of the inpatients received Access group antibiotics. Compliance with the local treatment guidelines was 53%.

Conclusions

This study found a high prevalence of prescribing and use of antibiotics in hospitalized patients across the surveyed hospitals in Zambia. The high use of Watch group antibiotics was above the recommended threshold indicating non-adherence to the WHO AWaRe guidelines for antibiotic use. Hence, there is a need to establish and strengthen antimicrobial stewardship programmes that promote the rational use of antibiotics in hospitals in Zambia.

Comprehensive Metagenomic Analysis of Veterinary Probiotics in Broiler Chickens

Probiotics are widely used in broiler chickens to support the gut microbiome, gut health, and to reduce the amount of antibiotics used. Despite their benefits, there is concern over their ability to carry and spread antimicrobial resistance genes (ARGs), posing a significant public health risk. This study utilized next-generation sequencing to investigate ARGs in probiotics approved for poultry, focusing on their potential to be transferred via mobile genetic elements such as plasmids and phages. We examined the gut microbiome and resistome changes in 60 broiler chickens over their rearing period, correlating these changes with different probiotic treatments. Specific resistance mechanisms against critically important antibiotics were identified, including genes related to fluoroquinolone resistance and peptide antibiotic resistance. We also found genes with significant relevance to public health (aadK, AAC(6')-Ii) and multiple drug-resistance genes (vmlR, ykkC, ykkD, msrC, clbA, eatAv). Only one phage-encoded gene (dfrA43) was detected, with no evidence of plasmid or mobile genetic element transmission. Additionally, metagenomic analysis of fecal samples showed no significant changes corresponding to time or diet across groups. Our findings highlight the potential risks associated with the use of probiotics in poultry, particularly regarding the carriage of ARGs. It is crucial to conduct further research into the molecular genetics of probiotics to develop strategies that mitigate the risk of resistance gene transfer in agriculture, ensuring the safe and effective use of probiotics in animal husbandry.

Antibacterial activity of gallic acid and methyl gallate against emerging non-fermenting bacilli

Stenotrophomonas maltophilia, Achromobacter xylosoxidans, and Burkholderia cenocepacia are considered emerging pathogens classified as a public health problem due to extensive antimicrobial resistance. Therefore, the discovery of new therapeutic strategies has become crucial. This study aimed to evaluate the antimicrobial activity of gallic acid and methyl gallate against non-fermenting bacteria. The study included five clinical isolates of Stenotrophomonas maltophilia, Achromobacter xylosoxidans, and Burkholderia cenocepacia. The minimum inhibitory concentrations of gallic acid and methyl gallate were determined by the broth microdilution method. Growth curves, metabolic activity, and biofilm formation of each bacterial strain in the presence or absence of phenolic compounds were performed. Finally, the therapeutic efficacy of the compounds was evaluated using an in vivo model. Gallic acid and methyl gallate showed antibacterial activity against bacterial strains in a concentration range of 64 to 256 µg/mL, both compounds reduced bacterial growth and metabolic activity of the strains, even at subinhibitory concentrations. Only, methyl gallate exhibited activity to inhibit the formation of bacterial biofilms. Moreover, gallic acid and methyl gallate increased larval survival by up to 60% compared to 30% survival of untreated larvae in a bacterial infection model in Galleria mellonella. Our results highlight the potential of gallic acid and methyl gallate as therapeutic alternatives for infections by emerging non-fermentative bacteria.

Developing a logic model for communication-based interventions on antimicrobial resistance (AMR)

The importance of communication in enhancing people's awareness and understanding of antimicrobial resistance (AMR) is consistently recognised in global and national action plans (NAPs). Despite this, there have been relatively few national AMR communication campaigns which use a structured approach to take account of the local context, encompass co-design with the target audience and use a logic model to help inform its design, implementation and evaluation. Designing a logic model for communication-based interventions can help map out the planning, resources, messaging, assumptions and intended outcomes of the campaign to maximise its impact, ensure it is fit for context and minimise any unintended consequences on individuals and society. Building on an AMR research project in Tanzania, Supporting the National Action Plan for AMR (SNAP-AMR), we co-designed the SNAP-AMR Logic Model with key stakeholders to implement AMR communication campaigns and related legacy materials to be employed in support of the Tanzanian NAP, but with broader relevance to a range of contexts. In developing the SNAP-AMR Logic Model, we reviewed relevant communication theories to create and target messages, and we considered behavioural change theories. We defined all key elements of the SNAP-AMR Logic Model as follows: (1) resources (inputs) required to enable the design and implementation of campaigns, e.g. funding, expertise and facilities; (2) activities, e.g. co-design of workshops (to define audience, content, messages and means of delivery), developing and testing of materials and data collection for evaluation purposes; (3) immediate deliverables (outputs) such as the production of legacy materials and toolkits; and (4) changes (outcomes) the campaigns aim to deliver, e.g. in social cognition and behaviours. The SNAP-AMR Logic Model efficiently captures all the elements required to design, deliver and evaluate AMR communication-based interventions, hence providing government and advocacy stakeholders with a valuable tool to implement their own campaigns. The model has potential to be rolled out to other countries with similar AMR socio-cultural, epidemiological and economic contexts.

In Silico Detection of Integrons and Their Relationship with Resistance Phenotype of Salmonella Isolates from a Brazilian Pork Production Chain

The pork production chain is an important reservoir of antimicrobial resistant bacteria. This study identified and characterized integrons in Salmonella isolates from a Brazilian pork production chain and associate them with their antibiotic resistance pattern. A total of 41 whole-genome sequencing data of nontyphoidal Salmonella were analyzed using PlasmidSPAdes and IntegronFinder software. Nine isolates (21.9%) had some integrons identified (complete and/or incomplete). Six complete class 1 integrons were found, with streptomycin resistance genes (aadA1, aadA2) alone or downstream of a trimethoprim resistance gene (dfrA1, dfrA12), and some also containing resistance genes for sulfonamides (sul1, sul3) and chloramphenicol (cmlA1). Class 2 integron was detected in only one isolate, containing dfrA1-sat2-aadA1 gene cassettes. Five isolates harbored CALINs-clusters attC but lacking integrases-with antimicrobial resistance genes typically found in integron structures. In all, integrons were observed among four serotypes: Derby, Bredeney, Panama, and monophasic var. Typhimurium I 4,[5],12:i:-. The association of integrons with antibiotic resistance phenotype showed that these elements were predominantly identified in multidrug resistance isolates, and six of the seven gentamicin-resistant isolates had integrons. So, surveillance of integrons in Salmonella should be performed to identify the potential for the spread of antimicrobial resistance genes among bacteria.

Assessment of antimicrobial resistance laboratory-based surveillance capacity of hospitals in Zambia: findings and implications for system strengthening

BACKGROUND

A well-established antimicrobial resistance (AMR) laboratory-based surveillance (LBS) is of utmost importance in a country like Zambia which bears a significant proportion of the world's communicable disease burden. This study assessed the capacity of laboratories in selected hospitals to conduct AMR surveillance in Zambia.

METHODS

This cross-sectional exploratory study was conducted among eight purposively selected hospitals in Zambia between August 2023 and December 2023. Data were collected using the self-scoring Laboratory Assessment of Antibiotic Resistance Testing Capacity (LAARC) tool.

FINDINGS

Of the assessed facilities, none had full capacity to conduct AMR surveillance with varying capacities ranging from moderate (63% (5/8)) to low (38% (3/8)). Some of the barriers of AMR-LBS were the lack of an electronic laboratory information system (63% (5/8)) and the lack of locally generated antibiograms (75% (6/8)). Quality control for antimicrobial susceptibility testing (AST), pathogen identification and media preparation had the lowest overall score among all of the facilities with a score of 14%, 20% and 44%, respectively. The highest overall scores were in specimen processing (79%), data management (78%), specimen collection, transport and management (71%), and safety (70%). Most facilities had standard operating procedures in place but lacked specimen-specific standard operating procedures.

CONCLUSION

The absence of laboratories with full capacity to conduct AMR surveillance hinders efforts to combat AMR and further complicates the treatment outcomes of infectious diseases. Establishing and strengthening LBS systems are essential in quantifying the burden of AMR and supporting the development of local antibiograms and treatment guidelines.

Disrupting quorum sensing as a strategy to inhibit bacterial virulence in human, animal, and plant pathogens

The development of sustainable alternatives to conventional antimicrobials is needed to address bacterial virulence while avoiding selecting resistant strains in a variety of fields, including human, animal, and plant health. Quorum sensing (QS), a bacterial communication system involved in noxious bacterial phenotypes such as virulence, motility, and biofilm formation, is of utmost interest. In this study, we harnessed the potential of the lactonase SsoPox to disrupt QS of human, fish, and plant pathogens. Lactonase treatment significantly alters phenotypes including biofilm formation, motility, and infection capacity. In plant pathogens, SsoPox decreased the production of plant cell wall degrading enzymes in Pectobacterium carotovorum and reduced the maceration of onions infected by Burkholderia glumae. In human pathogens, lactonase treatment significantly reduced biofilm formation in Acinetobacter baumannii, Burkholderia cepacia, and Pseudomonas aeruginosa, with the cytotoxicity of the latter being reduced by SsoPox treatment. In fish pathogens, lactonase treatment inhibited biofilm formation and bioluminescence in Vibrio harveyi and affected QS regulation in Aeromonas salmonicida. QS inhibition can thus be used to largely impact the virulence of bacterial pathogens and would constitute a global and sustainable approach for public, crop, and livestock health in line with the expectations of the One Health initiative.

Impact of a pharmacist-led educational intervention on knowledge, attitude, and practice toward the rational use of antibiotics among healthcare workers in a secondary care hospital in Punjab, Pakistan

Introduction: Growing antimicrobial resistance (AMR) and decreasing efficacy of the available antimicrobials have become a significant public health concern. The antimicrobial stewardship program (ASP) ensures the appropriate use of antimicrobials and mitigates resistance prevalence through various interventions. One of the core components of the ASP is to educate healthcare workers (HWs). Therefore, this study aims to identify the impact of a pharmacist-led educational intervention targeting knowledge, attitude, and practices regarding rational antibiotic use among healthcare professionals in a secondary care hospital in Punjab. Methods: This is a single-center, questionnaire-based, pre-post interventional study conducted over a six-month time period. Data analysis was conducted using SPSS version 26. Results: Regarding the pre-interventional knowledge, attitude, and practice (KAP) score of the respondents, 90.3% had a good knowledge score, 81.5% had a positive attitude, and 72.3% of HWs (excluding doctors) had a good practice score. Additionally, 74.6% of the doctors had a good practice score. After educational intervention, there was a significant improvement in the knowledge, attitude, and practice of the respondent HWs (p-value <0.001). Furthermore, males have higher knowledge scores compared to females in the pre- and post-intervention stages (p-value <0.05), and doctors differ from nurses regarding knowledge scores in both pre- and post-intervention stages. Conclusion: Considering educational programs as the backbone of the ASP, it is imperative to sustain efforts in the ongoing educational programs of HWs to foster high awareness and adherence to the ASP among HWs.

Public Patterns and Determinants of Antibiotic Self-Medication and Antibiotic Knowledge in Southern Jordan

Antibiotic self-medication, which refers to acquisition and using antibiotics to treat infections based on personal experience and/or without a doctor's advice or prescription, is a significant public health issue jeopardizing patient health outcomes. The purpose of the present cross-sectional online survey was to assess the frequency of self-medication among the general public in various geographical locations in southern Jordan, as well as to examine the determinants to self-medication. The survey was distributed through several social media networks over the period November-December 2022, and included demographic information as well as items related to the use and abuse of antibiotics, information sources about antibiotics, the duration of use of antibiotics, and assessment of the public knowledge about appropriate antibiotic use. Inferential analysis, such as the Chi-Square test and logistic regression, were adopted to assess the associations between the different variables with self-medication. A total of 984 respondents were enrolled in the study. Of these, 752 had been using antibiotics during the last year. However, the self-medicating cases were 413 of the 752. The main source of information about the utilization of antibiotics among participants in the survey was pharmacists. The participants commonly (36.0%) tended to use antibiotics until the symptoms disappeared. Nearly half of the respondents reported usually taking antibiotics for treating a runny nose (rhinorrhea). The logistic regression analysis indicated that self-medication with antibiotics was significantly associated with female gender (p-value < 0.001), low educational level (p-value = 0.014), rural living location (p-value 0.003), no health insurance (p-value = 0.001) and occupation (p-value = 0.005). Meanwhile age had no significant relationship to self-medication. Finally, the results revealed poor understanding of key appropriate antibiotic usage, which inevitably influences self-medication practice. It is crucial to come up with several programs and governmental policies to suppress widespread antibiotic self-medication as it will affect the health of future generations of Jordanian citizens.

Streptococcus suis Research Update: Serotype Prevalence and Antimicrobial Resistance Distribution in Swine Isolates Recovered in Spain from 2020 to 2022

This study aimed to update the Streptococcus suis serotype distribution in Spain by analysing 302 clinical isolates recovered from diseased pigs between 2020 and 2022. The main objectives were to identify prevalent serotypes, differentiate specific serotypes 1, 14, 2, and 1/2, investigate specific genotypic and phenotypic antimicrobial resistance features, and explore associations between resistance genes and phenotypic resistances. Serotypes 9 (21.2%), 1 (16.2%), 2 (15.6%), 3 (6%), and 7 (5.6%) were the most prevalent, whereas serotypes 14 and 1/2 corresponded with 4.3% and 0.7% of all isolates. Antimicrobial resistance genes, including tet(O), erm(B), lnu(B), lsa(E), tet(M), and mef(A/E), were analysed, which were present in 85.8%, 65.2%, 7%, 7%, 6.3%, and 1% of the samples, respectively. Susceptibility testing for 18 antimicrobials revealed high resistance levels, particularly for clindamycin (88.4%), chlortetracycline (89.4%), and sulfadimethoxine (94.4%). Notably, seven significant associations (p < 0.0001) were detected, correlating specific antimicrobial resistance genes to the observed phenotypic resistance. These findings contribute to understanding the S. suis serotype distribution and its antibiotic resistance profiles in Spain, offering valuable insights for veterinary and public health efforts in managing S. suis-associated infections.

Update of antimicrobial resistance in level III and IV health institutions in Colombia between January 2018 and December 2021

Introduction

Antimicrobial resistance surveillance is a fundamental tool for the development, improvement, and adjustment of antimicrobial stewardship programs, therapeutic guidelines, and universal precautions to limit the cross-transmission of resistant bacteria between patients. Since the beginning of 2020, the SARS-CoV-2 pandemic profoundly challenged the health system and, according to some reports, increased the rates of antimicrobial resistance.

Objective

To describe the behavior of antimicrobial resistance of the most frequent bacterial pathogens in twenty Colombian hospitals from January 2018 to December 2021.

Materials and methods

We conducted a descriptive study based on the microbiological information recorded from January 2018 to December 2021 in twenty levels III and IV health institutions in twelve Colombian cities. We identified the species of the ten most frequent bacteria along with their resistance profile to the antibiotic markers after analyzing the data through WHONET.

Results

We found no statistically significant changes in most pathogens’ resistance profiles from January 2018 to December 2021. Only Pseudomonas aeruginosa had a statistically significant increase in its resistance profile, particularly to piperacillin/tazobactam and carbapenems.

Conclusions

The changes in antimicrobial resistance in these four years were not statistically significant except for P. aeruginosa to piperacillin/tazobactam and carbapenems.

Assessment of antibiotic use patterns in bovine mastitis treatment in the dairy sector in Serbia

The dairy sector is essential for the world's food systems, playing a vital role in agricultural production. Yet, mastitis, an inflammation of the mammary gland, affects a considerable portion of the dairy cow population annually, leading to reduced productivity and sustainability. Insight into therapeutic protocols is essential for a better understanding of the situation on farms with the aim of developing new or harmonizing existing protocols in the mastitis treatment. This study conducted on dairy farm in Serbia aimed to explore the most commonly used antibiotics during bovine mastitis treatment and their association with daily milk yield. Data from 100 lactating cows, including therapeutic protocols, lactation numbers, mastitis episodes, milk yield, and antibiotic usage, were obtained from a computerized database and statistically analysed. The results demonstrated a high prevalence of narrow-spectrum antibiotics usage, with the majority of cows treated with combination therapy. The route of antibiotic application did not significantly impact daily milk yield, while treatment duration had no discernible effect. Nonetheless, specific antibiotics were associated with milk yield variations, suggesting the need for careful antibiotic selection and management in mastitis therapy. These findings emphasize the importance of prudent antibiotic use to safeguard animal health and long-term milk production sustainability.

Monitoring progress on Antimicrobial Resistance (AMR) response in the World Health Organization African region: Insights from the Tracking AMR Country Self-Assessment Survey (TrACSS) 2021 results for the human health sector

Antimicrobial resistance (AMR) is a major 21st century global health challenge. The WHO African Region Member States committed to develop and implement multisectoral national action plans (NAPs) that address AMR, in line with the Global Action Plan on AMR (GAP). The aim of this paper is to present the progress of AMR response in the WHO African Region based on the annual Tracking AMR Country Self-Assessment Survey (TrACSS), with a focus on human health indicators. This was a secondary data analysis of responses from forty-one countries that participated in the 2021 TrACSS. Of the 41 countries that responded to the 2021 TrACSS, 35(85%) have developed NAPs. Fifteen 15(37%) of countries have functional AMR multisector working groups. 55% (21/41) of countries are collating data nationally on AMR surveillance. Forty nine percent of countries conducted small-scale AMR awareness campaigns and 53% (21/41) covered AMR in some pre- and in-service training for human health workers. While 83% of countries reported having laws and regulations on the prescription and sale of antimicrobials, only 32% (13/41) have national systems for monitoring antimicrobial use. Twenty-three (58%, 23/41) reported having Infection Prevention and Control (IPC) programs at select health facilities. Countries have developed and are implementing AMR NAPs. Gaps still exist across key indicators monitored through TrACSS. Effective AMR response requires established functional multisectoral governance mechanisms in the One Health approach; political commitment, sustainable funding, and clear monitoring and reporting is critical.

The Prevalence of Alert Pathogens and Microbial Resistance Mechanisms: A Three-Year Retrospective Study in a General Hospital in Poland

The development of antibiotic resistance mechanisms hinders the treatment process. So far, there is limited data on the problem of bacterial resistance in hospitals in Central and Eastern Europe. Therefore, this study aimed to assess the prevalence of resistance mechanisms and alert pathogens based on reports regarding cultures of samples collected from general hospital patients in Poland in the period 2019-2021. This study examined the prevalence of resistance mechanisms and alert pathogens and the structure of microorganisms, including the type of diagnostic material in the hospital department. The frequency of occurrence and the trends were analysed based on Cochran's Q-test, relative change and the average annual rate of change (AARC). Of all 14,471 cultures, 3875 were positive for bacteria, and 737 were characterised by resistance mechanisms (19.0%). Alert pathogens were identified in 983 cases (24.6%), including pathogens isolated from blood samples. The most commonlyisolated bacteria were Escherichia coli (>20% of positive cultures), Enterococcus faecalis (7%), and Klebsiella pneumoniae (6%) increasing over time; Staphylococcus aureus (13%) was also found, but its proportion was decreasing over time. Extended-spectrum β-lactamase (ESBL) was the most frequent resistance mechanism in Internal Medicine (IM) (p < 0.001) and the Intensive Care Unit (ICU) (p < 0.01), as well as in ICU-COVID; this increased over the study period (AARC ↑34.9%). Methicillin-resistant Staphylococcus aureus (MRSA) (AARC ↓50.82%) and AmpC beta-lactamase (AARC ↓24.77%) prevalence fell over time. Also, the number of alert pathogens was dominant in the IM (p < 0.01) and ICU (p < 0.001). The most common alert pathogen was ESBL-positive E. coli. Gram-negative rods constitute a significant epidemiological problem in hospitals, especially the growing trend of ESBL in IM and ICU, which calls for increased control of sanitary procedures.

Point prevalence survey of antibiotic use and healthcare-associated infections in acute care hospitals: a comprehensive report from the Marche Region of Italy

BACKGROUND

Healthcare-associated infections (HAIs) and antimicrobial resistance (AMR) are serious health challenges. Point prevalence surveys (PPSs) are valuable tools for monitoring HAIs and AMR.

AIM

To describe results of the ECDC PPS 2022 dealing with the prevalence of HAIs, antimicrobial consumption, and associated factors, in acute care hospitals.

METHODS

The survey was performed in November 2022 in 14 hospitals according to the protocol proposed by the European Centre for Disease Prevention and Control. Multilevel logistic regression was performed using geographical area/hospital type as cluster variable to evaluate the factors independently associated with HAIs and antibiotics.

FINDINGS

The point prevalence of HAIs was 7.43%. Patients hospitalized for longer periods were more likely to have an HAI as well as those aged 15-44 years, with a rapidly fatal disease, intubated, and with one or two devices. Antibiotics prevalence was 47.30%. Males, unknown McCabe scores, minimally invasive/non-National Healthcare Safety Network (NHSN) surgery, patients with HAIs, hospitals with a higher alcohol hand-rub consumption, hospitals with a greater number of IPC personnel, geriatric wards, and hospitals with 300-600 beds were more likely to be under antimicrobial therapy.

CONCLUSION

This PPS provided valuable information on the prevalence of HAIs and antimicrobial consumption and variables associated. The high prevalence of HAIs highlights the need for improved infection control measures.

Migrants' living conditions, perceived health needs and implications for the use of antibiotics and antimicrobial resistance in the United Kingdom: A qualitative study

Background and Aims

Antimicrobial resistance (AMR) is among the top public health concerns around the globe. Migrants, especially forced migrants, could be at higher risk of acquiring and transmitting AMR during their journeys or in host countries. There is limited understanding regarding migrants' living conditions and the wider factors contributing to their risk of acquiring infections, and behaviors around antimicrobial use, and AMR development. In this study, we aimed to explore transit experiences, living conditions, and antibiotic use of migrants living in the United Kingdom.

Methods

We conducted semistructured qualitative interviews with 27 participants and identified five themes regarding migrants' journey and their living conditions during transit and after arriving in the United Kingdom, their access to water, sanitation and hygiene (WASH), and their use of antibiotics.

Results

Migrants, particularly forced migrants, experienced unfavorable living conditions, poor access to WASH, and challenges in accessing healthcare, which further contributed to health conditions like urinary and skin problems. Isolation and difficulty in accessing healthcare played significant roles in migrants' perceived need for storing and using antibiotics as a safety net.

Conclusion

The findings highlight the need for coordinated and multilevel interventions to address these challenges and contribute toward tackling AMR and improving the health of this population group.

Dendritic systems for bacterial outer membrane disruption as a method of overcoming bacterial multidrug resistance

The alarming rise of multi-drug resistant microorganisms has increased the need for new approaches through the development of innovative agents that are capable of attaching to the outer layers of bacteria and causing permanent damage by penetrating the bacterial outer membrane. The permeability (disruption) of the outer membrane of Gram-negative bacteria is now considered to be one of the main ways to overcome multidrug resistance in bacteria. Natural and synthetic permeabilizers such as AMPs and dendritic systems seem promising. However, due to their advantages in terms of biocompatibility, antimicrobial capacity, and wide possibilities for modification and synthesis, highly branched polymers and dendritic systems have gained much more interest in recent years. Various forms of arrangement, and structure of the skeleton, give dendritic systems versatile applications, especially the possibility of attaching other ligands to their surface. This review will focus on the mechanisms used by different types of dendritic polymers, and their complexes with macromolecules to enhance their antimicrobial effect, and to permeabilize the bacterial outer membrane. In addition, future challenges and potential prospects are illustrated in the hope of accelerating the advancement of nanomedicine in the fight against resistant pathogens.

Drivers of antimicrobial resistance in layer poultry farming: Evidence from high prevalence of multidrug-resistant Escherichia coli and enterococci in Zambia

Background and Aim

Inappropriate use of antimicrobials exacerbates antimicrobial resistance (AMR) in the poultry sector. Information on factors driving AMR in the layer poultry sector is scarce in Zambia. This study examined the drivers of AMR in the layer poultry sector in the Lusaka and Copperbelt Provinces of Zambia.

Materials and Methods

This cross-sectional study employed a structured questionnaire in 77 layer poultry farms in the provinces of Lusaka and Copperbelt, Zambia, from September 2020 to April 2021. Data analysis was conducted using Stata version 16.1. Antimicrobial resistance was defined as the presence of multidrug resistance (MDR) isolates. Multivariable regression analysis was used to identify drivers of AMR.

Results

In total, 365 samples were collected, from which 339 (92.9%) Escherichia coli and 308 (84.4%) Enterococcus spp. were isolated. Multidrug resistance was identified in 39% of the E. coli and 86% of the Enterococcus spp. The overall prevalence of AMR in layer poultry farms was 51.7% (95% confidence interval [CI]: 40.3%-63.5%). Large-scale farmers (Adjusted odds ratio [AOR] = 0.20, 95% CI: 0.04%-0.99%) than small-scale and farmers who were aware of AMR than those who were unaware (AOR = 0.26, 95% CI: 0.08%-0.86%) were less likely to experience AMR problems.

Conclusion

This study found a high prevalence of AMR in layer poultry farming linked to the type of farm management practices and lack of AMR awareness. Evidence of high MDR in our study is of public health concern and requires urgent attention. Educational interventions must increase AMR awareness, especially among small- and medium-scale poultry farmers.

Antimicrobial Resistance in Escherichia coli and Its Correlation with Antimicrobial Use on Commercial Poultry Farms in Bangladesh

Antimicrobial resistance is a global concern, posing risks to human and animal health. This research quantified antimicrobial resistance (AMR) in E. coli isolates from poultry fecal and environmental samples in Bangladesh and explored their association with antimicrobial use (AMU). We screened 725 fecal and 250 environmental samples from 94 conventional broilers and 51 Sonali farms for E. coli presence using MALDI-TOF mass spectrometry. AMU data were collected at flock levels, expressed as treatment incidence (TI), while minimum inhibitory concentrations (MIC) for 14 antibiotics were determined on five fecal E. coli isolates per farm and on all environmental isolates. MIC results were interpreted using human clinical breakpoints and EUCAST epidemiological cut-off values (ECOFFs). Acquired resistance against commonly used antimicrobial agents such as ciprofloxacin, tetracycline and ampicillin, was extremely high and predominantly clinically relevant. There was a moderate correlation between fecal and environmental antibiotic resistance index (ARI), but there was no significant correlation between AMU and AMR, suggesting that the observed AMR prevalence is unrelated to current AMU in poultry, but may be due to high historical AMU. A high level of multidrug resistance, including against critically important antimicrobials, was found in both farm types. Therefore, an AMR/AMU surveillance program is urgently needed in the poultry production sector of Bangladesh.

Scope and applicability of social-ecological resilience to antimicrobial resistance

Social-ecological systems conceptualise how social human systems and ecological natural systems are intertwined. In this Personal View, we define the scope and applicability of social-ecological resilience to antimicrobial resistance. Resilience to antimicrobial resistance corresponds to the capacity to maintain the societal benefits of antimicrobial use and One Health systems' performance in the face of the evolutionary behaviour of microorganisms in response to antimicrobial use. Social-ecological resilience provides an appropriate framework to make sense of the disruptive impacts resulting from the emergence and spread of antimicrobial resistance; capture the diversity of strategies needed to tackle antimicrobial resistance and to live with it; understand the conditions that underpin the success or failure of interventions; and appreciate the need for adaptive and coevolutionary governance. Overall, resilience thinking is essential to improve understanding of how human societies dynamically can cope with, adapt, and transform to the growing global challenge of antimicrobial resistance.

In Silico Studies of Indole Derivatives as Antibacterial Agents

Objectives

Molecular docking and QSAR studies of indole derivatives as antibacterial agents.

Methods

In this study, we used a multiple linear regressions (MLR) approach to construct a 2D quantitative structure activity relationship of 14 reported indole derivatives. It was performed on the reported antibacterial activity data of 14 compounds based on theoretical chemical descriptors to construct statistical models that link structural properties of indole derivatives to antibacterial activity. We have also performed molecular docking studies of same compounds by using Maestro module of Schrodinger. A set the molecular descriptors like hydrophobic, geometric, electronic and topological characters were calculated to represent the structural features of compounds. The conventional antibiotics sultamicillin and ampicillin were not used in the model development since their structures are different from those of the created compounds. Biological activity data was first translated into pMIC values (i.e. -log MIC) and used as a dependent variable in QSAR investigation.

Results

Compounds with high electronic energy and dipole moment were effective antibacterial agents against S. aureus, indole derivatives with lower κ₂ values were excellent antibacterial agents against MRSA standard strain, and compounds with lower R value and a high ²χ^v value were effective antibacterial agents against MRSA isolate.

Conclusion

Compounds 12 and 2 showed better binding score against penicillin binding protein 2 and penicillin binding protein 2a respectively.

A Genomic Snapshot of Antibiotic-ResistantEnterococcus faecalis within Public Hospital Environments in South Africa

Enterococci are among the most common opportunistic hospital pathogens. This study used whole-genome sequencing (WGS) and bioinformatics to determine the antibiotic resistome, mobile genetic elements, clone and phylogenetic relationship of Enterococcus faecalis isolated from hospital environments in South Africa. This study was carried out from September to November 2017. Isolates were recovered from 11 frequently touched sites by patients and healthcare workers in different wards at 4 levels of healthcare (A, B, C, and D) in Durban, South Africa. Out of the 245 identified E. faecalis isolates, 38 isolates underwent whole-genome sequencing (WGS) on the Illumina MiSeq platform, following microbial identification and antibiotic susceptibility tests. The tet(M) (31/38, 82%) and erm(C) (16/38, 42%) genes were the most common antibiotic-resistant genes found in isolates originating from different hospital environments which corroborated with their antibiotic resistance phenotypes. The isolates harboured mobile genetic elements consisting of plasmids (n = 11) and prophages (n = 14) that were mostly clone-specific. Of note, a large number of insertion sequence (IS) families were found on the IS3 (55%), IS5 (42%), IS1595 (40%), and Tn3 transposons the most predominant. Microbial typing using WGS data revealed 15 clones with 6 major sequence types (ST) belonging to ST16 (n = 7), ST40 (n = 6), ST21 (n = 5), ST126 (n = 3), ST23 (n = 3), and ST386 (n = 3). Phylogenomic analysis showed that the major clones were mostly conserved within specific hospital environments. However, further metadata insights revealed the complex intraclonal spread of these E. faecalis major clones between the sampling sites within each specific hospital setting. The results of these genomic analyses will offer insights into antibiotic-resistantE. faecalis in hospital environments relevant to the design of optimal infection prevention strategies in hospital settings.

Four years after the implementation of antimicrobial stewardship program in Jordan: evaluation of program's core elements

Objectives

To combat antimicrobial resistance, the World Health Organization (WHO) urged healthcare organizations in Low- and Middle-Income Countries (LMICs) to implement the core elements of the antimicrobial stewardship (AMS) programs. In response, Jordan took action and developed a national antimicrobial resistance action plan (NAP) in 2017 and commenced the AMS program in all healthcare facilities. It is paramount to evaluate the efforts to implement the AMS programs and understand the challenges of implementing a sustainable and effective program, in Low-Middle Income Country (LMIC) contexts. Therefore, the aim of this study was to appraise the compliance of public hospitals in Jordan to the WHO core elements of effective AMS programs after 4 years of commencement.

Methods

A cross-sectional study in public hospitals in Jordan, using the WHO AMS program core elements for LMICs was carried out. The questionnaire comprised 30 questions that covered the program's six core elements: leadership commitment, accountability and responsibility, AMS actions, education and training, monitoring, and evaluation, and reporting and feedback. A five-point Likert scale was employed for each question.

Results

A total of 27 public hospitals participated, with a response rate of 84.4%. Adherence to core elements ranged from (53%) in the leadership commitment domain to (72%) for AMS procedure application (actions). Based on the mean score, there was no significant difference between hospitals according to location, size, and specialty. The most neglected core elements that emerged as top priority areas were the provision of financial support, collaboration, access, as well as monitoring and evaluation.

Conclusion

The current results revealed significant shortcomings in the AMS program in public hospitals despite 4 years of implementation and policy support. Most of the core elements of the AMS program were below average, which requires hospital leadership commitment, and multifaceted collaborative actions from the concerned stakeholders in Jordan.

Performance of a Pilot-Scale Continuous Flow Ozone-Based Hospital Wastewater Treatment System

Antimicrobial resistance (AMR) is becoming a global concern. Recently, research has emerged to evaluate the human and environmental health implications of wastewater from medical facilities and to identify acceptable wastewater treatment methods. In this study, a disinfection wastewater treatment system using an ozone-based continuous flow system was installed in a general hospital located in Japan. The effectiveness of antimicrobial-resistant bacteria (ARB) and antimicrobials in mitigating the environmental impact of hospital wastewater was evaluated. Metagenomic analysis was conducted to characterize the microorganisms in the wastewater before and after treatment. The results demonstrated that ozone treatment enables effective inactivation of general gut bacteria, including Bacteroides, Prevotella, Escherichia coli, Klebsiella, DNA molecules, and ARGs, as well as antimicrobials. Azithromycin and doxycycline removal rates were >99% immediately after treatment, and levofloxacin and vancomycin removal rates remained between 90% and 97% for approximately one month. Clarithromycin was more readily removed than the other antimicrobials (81-91%), and no clear removal trend was observed for ampicillin. Our findings provide a better understanding of the environmental management of hospital wastewater and enhance the effectiveness of disinfection wastewater treatment systems at medical facilities for mitigating the discharge of pollutants into aquatic environments.

Exploring Nanotechnology as a Strategy to Circumvent Antimicrobial Resistance in Bone and Joint Infections

Bone and joint infections (BJIs) are difficult to treat, necessitating antimicrobial therapy at high doses for an extended period of time, in some cases different from our local guidelines. As a consequence of the rise in antimicrobial-resistant organisms, drugs that were previously reserved for last-line defense are now being used as first line treatment, and the pill burden and adverse effects on patients are leading to nonadherence, encouraging antimicrobial resistance (AMR) to these last-resort medicines. Nanodrug delivery is the field of pharmaceutical sciences and drug delivery which combines nanotechnology with chemotherapy and/or diagnostics to improve treatment and diagnostic outcomes by targeting specific cells or tissues affected. Delivery systems based on lipids, polymers, metals, and sugars have been used in an attempt to provide a way around AMR. This technology has the potential to improve drug delivery by targeting the site of infection and using the appropriate amount of antibiotics to treat BJIs caused by highly resistant organisms. This Review aims to provide an in-depth examination of various nanodrug delivery systems used to target the causative agents in BJI.

Antibiotics with novel mode of action as new weapons to fight antimicrobial resistance

Antimicrobial resistance (AMR) is a major public health issue, causing 5 million deaths per year. Without any action plan, AMR will be in a near future the leading cause of death ahead of cancer. AMR comes from the ability of bacteria to rapidly develop and share resistance mechanisms towards current antibiotics, rendering them less effective. To circumvent this issue and avoid the phenomenon of cross-resistance, new antibiotics acting on novel targets or with new modes of action are required. Today, the pipeline of potential new treatments with these characteristics includes promising compounds such as gepotidacin, zoliflodacin, ibezapolstat, MGB-BP-3, CRS-3123, afabicin and TXA-709, which are currently in clinical trials, and lefamulin, which has been recently approved by FDA and EMA. In this review, we report the chemical synthesis, mode of action, structure-activity relationships, in vitro and in vivo activities as well as clinical data of these eight small molecules listed above.

Antibiotic Resistance and Food Safety: Perspectives on New Technologies and Molecules for Microbial Control in the Food Industry

Antibiotic resistance (ABR) has direct and indirect repercussions on public health and threatens to decrease the therapeutic effect of antibiotic treatments and lead to more infection-related deaths. There are several mechanisms by which ABR can be transferred from one microorganism to another. The risk of transfer is often related to environmental factors. The food supply chain offers conditions where ABR gene transfer can occur by multiple pathways, which generates concerns regarding food safety. This work reviews mechanisms involved in ABR gene transfer, potential transmission routes in the food supply chain, the prevalence of antibiotic residues in food and ABR organisms in processing lines and final products, and implications for public health. Finally, the paper will elaborate on the application of antimicrobial peptides as new alternatives to antibiotics that might countermeasure ABR and is compatible with current food trends.

Investigating Catheter-Related Infections in Southern Benin Hospitals: Identification, Susceptibility, and Resistance Genes of Involved Bacterial Strains

The use of catheters and bladder catheters in hospitals can increase the risk of bacterial infections. This study aimed to identify the bacterial strains involved in catheter-related infections (CRI) in southern Benin hospitals. The study included 407 samples, including 95 catheter tip samples and 312 urine samples collected from bladder catheters from patients on the first day and 48 h after admission. The catheter tip samples were analyzed using traditional bacterial isolation and identification methods, while the urine samples were analyzed using VITEK-2. Antibiotic sensitivity was tested using the Kirby Bauer method, and virulence and resistance genes were detected through standard PCR. The results showed a predominance of Escherichia coli (53.5%), Klebsiella pneumoniae (23.3%), and Enterobacter aerogenes (7.0%) among Gram-negative bacilli, and coagulase-negative Staphylococcus as the most identified cocci. Bacterial susceptibility to antibiotics showed variable levels of resistance, with blaTEM being detected in 42.9% of identified bacterial species, followed by blaSHV (26.2%) and blaCTX-M-15 (16.7%). The blaNDM gene was only found in three identified bacterial strains, while vanA and vanB genes were detected in 3.2% of strains with a prevalence of 55% for the mecA gene. A prevalence of 18.8% for fimH was noted for the virulence genes. In conclusion, this study highlights the importance of following proper hygiene and aseptic practices during catheterization to effectively prevent CRIs. These findings should be used to improve interventions in hospitals and reduce healthcare-associated infections in developing countries.

The Assessment of Antimicrobial and Anti-Biofilm Activity of Essential Oils against Staphylococcus aureus Strains

The increase in antimicrobial resistance and tolerance over the years has become a serious public health problem, leading to the inevitable development of alternative antimicrobial agents as substitutes for industrial pharmaceutical antibiotics targeting humans and animals under the concept of one health. Essential oils (EOs) extracted from aromatic and pharmaceutical plants incorporate several bioactive compounds (phytochemicals) that positively affect human and animal health. Herein, this work aimed to examine a standardized chemical composition and screen the antimicrobial and anti-biofilm activity of Thymus sibthorpii, Origanum vulgare, Salvia fruticosa, and Crithmum maritimum EOs against three different Staphylococcus aureus strains by gold-standard disc diffusion, broth microdilution, and microtiter plate biofilm assays. Therefore, the evaluation of the above-mentioned EOs were considered as substitutes for antibiotics to combat the ever-mounting antimicrobial resistance problem. The observed bacterial growth inhibition varied significantly depending on the type and concentration of the antimicrobials. Thymus sibthorpii was determined as the strongest antimicrobial, with 0.091 mg/mL minimum inhibitory concentration (MIC) and a 14-33 mm diameter inhibition zone at 5% (v/v) concentration. All tested EOs indicated almost 95% inhibition of biofilm formation at their half MIC, while gentamicin sulfate did not show sufficient anti-biofilm activity. None of the methicillin-resistant strains showed resistance to the EOs compared to methicillin-sensitive strains. Thymus sibthorpii and Origanum vulgare could be potential alternatives as antimicrobial agents to overcome the problem of microbial resistance. The tested EOs might be incorporated into antimicrobial products as safe and potent antimicrobial and anti-biofilm agents.

Antibacterial and anti-inflammatory activity of plant species used in traditional poultry ethnomedicine in Zimbabwe: A first step to developing alternatives to antibiotic poultry feed additives

ETHNOPHARMACOLOGICAL RELEVANCE

Global interest in phytogenic feed additives as alternatives to antibiotics in feed has been spurred by the banning of antibiotic growth promoters by several countries. Suitable plant extracts for development of phytogenic feed additives should have therapeutic value and should also be safe.

AIM OF STUDY

The aim of this study was to evaluate the antibacterial, antioxidant and anti-lipoxygenase activities as well as cytotoxicity of selected plant species used in poultry ethnomedicine in Zimbabwe.

METHODS

Antibacterial activity was determined against three ATCC strains (Staphylococcus aureus, Escherichia coli, Salmonella Enteritidis) and two clinical strains isolated from chickens (Escherichia coli and Salmonella Gallinarum) using a two-fold serial microdilution assay. Qualitative antibacterial bioautography was also carried out using the ATCC strains. Antioxidant activities of crude acetone and methanol extracts were determined using free radical scavenging assays whilst anti-lipoxygenase activity was evaluated using a ferrous oxidation-xylenol orange (FOX) assay. Cytotoxicity was evaluated using a tetrazolium-based colorimetric assay (MTT assay) on Vero monkey kidney cells.

RESULTS

Erythrina abyssinica had the best antibacterial activity against both ATCC strains and clinical strains with minimum inhibitory concentration (MIC) values ranging from 0.02 to 0.156 mg/ml. Aloe greatheadii, Adenia gummifera (leaves), Senna singueana and Aloe chabaudii had moderate activity against the poultry pathogens. Bioautography showed that all ten plant species have antibacterial activity against the tested microorganisms with E. abyssinica and S. singueana having prominent bands of inhibition against both Gram-negative and Gram-positive bacteria. The acetone extract of S. singueana and the methanol extract of Euphorbia matabelensis had the most powerful antioxidant activities with mean IC₅₀ values of 1.43 μg/ml and 1.31 μg/ml respectively in the ABTS assay which were comparable with those of the positive controls (ascorbic acid and trolox). Bobgunnia madagascariensis, A. chabaudii, E. abyssinica and Tridactyle bicaudata extracts had reasonable antioxidant activity. The S. singueana extract had the most potent anti-lipoxygenase activity with a mean IC₅₀ value of 1.72 μg/ml. The cytotoxicity results showed that only the acetone extracts of A. greatheadii and S. singueana were relatively safe at concentrations that were active against the tested microorganisms (selective index >1). Regarding anti-lipoxygenase activity, extracts of B. madagascariensis, S. singueana, T. bicaudata and E. matabelensis were more active than toxic (selective index >5) indicating anti-inflammatory potential.

CONCLUSIONS

This study showed that S. singueana had a cocktail of therapeutic activity and supports further investigation of this plant species for development of phytogenic poultry feed additives. Other plant species with noteworthy biological activities include B. madagascariensis, E. abyssinica, A. greatheadii, T. bicaudata and E. matabelensis.

Antibiotic resistance of Escherichia coli from the milk of Ettawa crossbred dairy goats in Blitar Regency, East Java, Indonesia

Background and Aim

Antimicrobial resistance, especially antibiotic resistance, is one of the most severe public health challenges. Antibiotic resistance occurs when bacteria avoid and fight the mechanism of action of antibiotic drugs. This study aimed to determine the resistance of Escherichia coli from the milk of Ettawa crossbreed dairy goat at Blitar Regency, East Java, Indonesia, with the antibiotics streptomycin, sulfonamides, and trimethoprim.

Materials and Methods

A total of 34 milk samples of Ettawa crossbreed dairy goats were used in this study. The initial stages of this research included tests of the physical properties, isolation, and identification of E. coli. Then, the E. coli isolates were tested for antibiotic resistance using the Kirby-Bauer method.

Results

The results showed that all samples were positive for E. coli. The physical properties of milk, namely, color, odor, flavor, and consistency, were normal. The results of the alcohol test showed normal acidity, and the specific gravity of goat milk met the criteria, with an average specific gravity of 1.0295 g/mL. The results of the antibiotic resistance test showed that 4 (12%) samples were resistant to streptomycin, 5 (15%) to sulfonamide, and 3% to trimethoprim.

Conclusion

The prevalence of E. coli from Ettawa crossbreed dairy goats in Blitar Regency, East Java, Indonesia, was 100%. Furthermore, this E. coli isolate exhibited resistance to antibiotics streptomycin, sulfonamides, and trimethoprim. The use of antibiotics in the dairy goat industry in Indonesia should be controlled to prevent the spread of resistant E. coli from animals to humans through the food chain and prevent the emergence of multidrug-resistant E. coli.

Is There a Relationship between Antimicrobial Use and Antibiotic Resistance of the Most Common Mastitis Pathogens in Dairy Cows?

Antimicrobials have had an important impact on animal health and production performance. However, non-prudent antimicrobial use (AMU) in food producing animals is considered to contribute to the emergence of antimicrobial resistance (AMR), with a potential impact on both animal and public health. Considering the global importance of AMR, and the threats and challenges posed by mastitis and mastitis therapy in livestock production, the main objective of this study was to quantify AMU on three dairy farms in Serbia and to examine whether there is an association between AMU and the emergence of antimicrobial resistance of mastitis-associated pathogens. Antimicrobial susceptibility testing was performed by the disk diffusion method using causative agents isolated from the milk samples of 247 dairy cows. AMU data were obtained for a one-year period (May 2021 to May 2022) based on antibiotic prescriptions listed in electronic databases kept by farm veterinarians. To estimate antimicrobial drug exposure at the farm level, the veterinary drug Defined Daily Dose was calculated by multiplying the total amount of antibiotic used on the farms during the study period by the quantity of antibiotic in the administered drug and number of original drug packages used. The results on the association between the use of common antibiotics in mastitis treatment and AMR of isolated mastitis-associated pathogens confirm a pattern that could raise awareness of the importance of this aspect of good veterinary and clinical practice to combat the global threat of AMR.

Plant-derived nanoparticles as alternative therapy against Diarrheal pathogens in the era of antimicrobial resistance: A review

Diarrhea is a condition in which feces is discharged from the bowels frequently and in a liquid form. It is one of the frequent causes of morbidity and mortality in developing countries. The impact of Diarrhea is worsened by the increasing incidence of antimicrobial resistance among the causative agents, and this is now categorized as a global healthcare challenge. Antimicrobial resistance among Diarrheal pathogens also contributes to extended infection durations, and huge economic loss even in countries with advanced public health policies. The ever-increasing incidence of antimicrobial resistance including the contraindications arising from the administration of antibiotics in some Diarrheal cases highlights a crucial need for the development of novel non-antibiotic alternative agents for therapeutic and biocontrol applications. One such intervention includes the application of plant-derived nanoparticles (PDNPs) with novel antimicrobial properties. Given their small size and large surface area to volume ratio, PDNPs can attack target bacterial cell walls to generate reactive oxygen species that may simultaneously disrupt bacteria cell components such as DNA and proteins leading to cell damage or death. This potential can make it very difficult for pathogenic organisms to develop resistance against these antibacterial agents. In this review, we provide a critical overview on the antimicrobial resistance crisis among Diarrheagenic bacteria. We also discuss the evidence from the existing literature to support the potential associated with the use of PDNPs as alternative therapeutic agents for multidrug resistant and antibiotics administer contraindicated bacteria that are associated with Diarrhea.

Estimating the effect of practicing nursing professionals density on cumulative carbapenem-resistance prevalence in gram-negative invasive Isolates: a 30 European country observational modeling study

Background

The burden of antimicrobial-resistance, specifically carbapenem-resistance in gram-negative bacteria (CRGN), presents a serious public health threat worldwide. In Europe, Southern and Eastern countries (SEC) display a higher CRGN-prevalence as compared to Northern and Western countries (NWC). Since SEC also display lower nurse-density on average, we hypothesized that the occurrence of CRGN might correlate with nurse understaffing and therefore aimed at quantifying a potential independent effect of nurse-density on total CRGN in Europe.

Methods

A 30-country cross-sectional study was conducted. Cumulative six-year CRGN-prevalence (2011–2016) in four gram-negative bacterial species was determined based on > 700 k clinical invasive isolates (EARS-net). We performed multivariable log-linear regression to provide estimations of the effect of nurse-density while adjusting to various health-system variables.

Results

Multivariable analysis (adj.-R² ~ 93%) suggested an average 0.4% [95%-CI 0.2–1.0%] CRGN-increase due to a decrement of one practicing nurse per week of hospital-stay of one population individual. Our modeling provided CRGN-estimations in two non-EARS-net countries (Switzerland and Turkey), which were almost equal to empirically estimated values (CAESAR-Network). Furthermore, a nurse-density-dependent moderation of the inter-species distribution balance was a likely pathway of the observed effect. These observations were specific for CRGN, in contrast to other resistance types in the same species.

Conclusions

This is the first attempt of quantifying potential nurse-density effects on antimicrobial-resistance at national level. Our results suggest an increase in CRGN by decreasing nurse-density. Nurse-density is thus a novel factor that might improve our understanding of the unbalanced CRGN-distribution among sub-European regions. Consequently, integrating nurse-density in future AMR-policies could be beneficial.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13756-022-01076-0.

Knowledge, attitudes and practices regarding antimicrobial usage, spread and resistance emergence in commercial poultry farms of Rajshahi district in Bangladesh

Background

Inappropriate and injudicious use of antimicrobials in broiler and layer farms has become a common practice in lower and middle-income countries including Bangladesh. This study aimed to assess poultry farmers’ knowledge, attitude, and practices regarding antimicrobial usage (AMU), and their beliefs in factors that affect antimicrobial resistance (AMR) spread and emergence in humans through commercial poultry farms in Bangladesh.

Methods

A cross-sectional study was conducted among 204 farmers (95.6% male; mean_age = 35.14 ± 10.25 years) in the Rajshahi district of Bangladesh who were recruited from three upazilas (sub-districts) through a multistage sampling technique. Data were collected from June to November 2021 via face-to-face interviews using a semi-structured questionnaire.

Results

The proportion of farmers who reported having received information regarding AMU from veterinarians was higher in layer compared to broiler farms (65.9% vs. 44.9%, p < 0.001). A higher proportion of layer compared to broiler farmers believed that antimicrobial residues and pathogens in poultry can pass to humans through the consumption of contaminated eggs (28.1% vs. 5.8%, p < 0.05). The mean score of the farmers’ attitude towards addressing AMU was 4.49 (SD = 1.37) out of 7, with the higher score indicating a better attitude. The mean score of better attitudes towards addressing AMU was significantly higher among educated participants (bachelor’s or higher levels of education (p = 0.006). A higher proportion of layer (56.3%) farmers did not keep a record of AMU when compared to broiler farmers (37.7%) (p = 0.012). More broiler (50.7%) compared to layer (38.5%) farmers continued using the full dose of antimicrobials (p = 0.042). The most frequently used antimicrobials in broiler and layer poultry farms were Colistin (broiler vs layer: 73.9% vs. 86.75%; p = 0.024), and Ciprofloxacin (broiler vs. layer: 95.7% vs. 84.4%; p = 0.021). Farmers’ beliefs were significantly associated with the spread of AMR pathogens from contaminated eggs to humans (p < 0.001).

Conclusions

The findings reflected that majority of farmers had inadequate knowledge of AMU, less knowledgeable beliefs aboutAMU, and inappropriate AMU (e.g., poor record keeping, incomplete doses) in chicken production systems. The government should ensure education or advisory services for poultry farmers on proper AMU, enforce current veterinary laws and regulations on antimicrobials, and implement AMU surveillance systems.

Public Knowledge, Attitudes, and Practices Towards Antibiotic Use and Antimicrobial Resistance in the Western Region of Saudi Arabia

Introduction Antimicrobial resistance (AMR) is one of the major concerns for global health. Inappropriate use of antibiotics is speeding up the process of AMR. The aim of this study was to assess the knowledge, attitude, and practices (KAP) of the population of the western region of Saudi Arabia towards antibiotic use and AMR. Methods A cross-sectional study was conducted using an online questionnaire via social media platforms. It consisted of four parts: first, the participant's sociodemographic characteristics. Second, an assessment of the knowledge of antibiotic use and AMR. The third and fourth parts are to evaluate the attitude and practices towards antibiotic use and AMR. Results From a total of 501 participants, 379 (75.6%) were females, and 354 (70.7%) of the participants had a college degree. Regarding the overall knowledge of antibiotics and AMR, 277 (55.29%) of the respondents had poor knowledge. In addition, 443 (88.42%) of the participants also reported having an inadequate attitude. Moreover, inadequate practices related to the use of antibiotics were also reported among 305 (60.89%) of the participants. Factors associated with the level of knowledge are gender, age, educational level, and occupational status. Regarding occupation, being in a medical job was associated with a better knowledge of antibiotics and AMR than other occupations. Conclusion Our study revealed poor overall knowledge, attitudes, and practices toward antibiotics and AMR among participants. Conducting educational health campaigns for the public that aim to promote awareness and enhance good practices, emphasizing the role of health care providers in health education for the public, and enforcing strict regulations to control the non-prescription dispensing of antibiotics will help to combat this issue. However, future research on this topic is required.

Antimicrobial Resistance in the Food Chain: Trends, Mechanisms, Pathways, and Possible Regulation Strategies

Antimicrobial resistance (AMR) remains of major interest for different types of food stakeholders since it can negatively impact human health on a global scale. Antimicrobial-resistant bacteria and/or antimicrobial resistance genes (transfer in pathogenic bacteria) may contaminate food at any stage, from the field to retail. Research demonstrates that antimicrobial-resistant bacterial infection(s) occur more frequently in low- and middle-income countries (LMICs) than in developed countries. Worldwide, foodborne pathogens are a primary cause of morbidity and mortality. The spread of pathogenic bacteria from food to consumers may occur by direct or indirect routes. Therefore, an array of approaches both at the national and international level to control the spread of foodborne pathogens and promote food safety and security are essential. Zoonotic microbes can spread through the environment, animals, humans, and the food chain. Antimicrobial drugs are used globally to treat infections in humans and animals and prophylactically in production agriculture. Research highlights that foods may become contaminated with AMR bacteria (AMRB) during the continuum from the farm to processing to retail to the consumer. To mitigate the risk of AMRB in humans, it is crucial to control antibiotic use throughout food production, both for animal and crop agriculture. The main inferences of this review are (1) routes by which AMRB enters the food chain during crop and animal production and other modes, (2) prevention and control steps for AMRB, and (3) impact on human health if AMR is not addressed globally. A thorough perspective is presented on the gaps in current systems for surveillance of antimicrobial use in food production and/ or AMR in the food chain.

Distribution and characteristics of carbapenem-resistant and extended-spectrum β-lactamase (ESBL) producing Escherichia coli in hospital effluents, sewage treatment plants, and river water in an urban area of Japan

Occurrence of profiles of the carbapenem-resistant Escherichia coli (CRE-E) and extended-spectrum β-lactamase (ESBL)-producing Escherichia coli (ESBL-E) in an urban river in a sub-catchment of the Yodo River Basin, one of the representative water systems of Japan was investigated. We conducted seasonal and year-round surveys for the antimicrobial-resistant bacteria (AMRB) and antimicrobial-resistance genes (AMRGs) in hospital effluents, sewage treatment plant (STP) wastewater, and river water; subsequently, contributions to wastewater discharge into the rivers were estimated by analyses based on the mass flux. Furthermore, the characteristics of AMRB in the water samples were evaluated on the basis of antimicrobial susceptibility tests. CRE-E and ESBL-E were detected in all water samples with mean values 11 and 1900 CFU/mL in the hospital effluent, 58 and 4550 CFU/mL in the STP influent, not detected to 1 CFU/mL in the STP effluent, and 1 and 1 CFU/mL in the STP discharge into the river, respectively. Contributions of the pollution load derived from the STP effluent discharged into the river water were 1 to 21%. The resistome profiles for bla_IMP, bla_TEM, and bla_CTX-M genes in each water sample showed that AMRGs were not completely removed in the wastewater treatment process in the STP, and the relative abundances of bla_IMP, bla_TEM, and bla_CTX-M genes were almost similar (P<0.05). Susceptibility testing of antimicrobial-resistant E. coli isolates showed that CRE-E and ESBL-E detected in wastewaters and river water were linked to the prevalence of AMRB in clinical settings. These results suggest the importance of conducting environmental risk management of AMRB and AMRGs in the river environment. To our knowledge, this is the first detailed study that links the medical environment to CRE-E and ESBL-E for evaluating the AMRB and AMRGs in hospital effluents, STP wastewater, and river water at the basin scale on the basis of mass flux as well as the contributions of CRE-E and ESBL-E to wastewater discharge into the river.

Occurrence of Healthcare-Associated Infections (HAIs) by Escherichia coli and Klebsiella spp. Producing Extended-Spectrum β-lactamases (ESBL) and/or Carbapenemases in Portuguese Long-Term Care Facilities

Extended-spectrum-β-lactamase (ESBL)- and carbapenemase-producing bacteria are widespread in hospitals, but the extent of this problem in long-term care facilities (LTCFs) is poorly understood. We aimed to elucidate, in the Portuguese regional clinical context, the relevance of LTCFs as a reservoir of Escherichia coli and Klebsiella spp. producing ESBL- and/or carbapenemases (Ec/Kp-ESBL/CARB). Fourteen LTCFs from Portugal, corresponding to units of convalescence (UC/n = 3), medium-term internment and rehabilitation (UMDR/ n = 5), or long-term internment and maintenance (ULDM/n = 6), were analyzed (2016–2019). All patients with Ec/Kp-ESBL/CARB infections acquired during LTCF stay were included, and detailed information was collected. Prevalence of patients with healthcare-associated infections (HAIs) by Ec/Kp-ESBL/CARB did not vary significantly over time (1.48% in 2016–2017, 1.89% in 2017–2018, and 1.90% in 2018–2019), but a statistically significant association with the LTCF typology (ULDM, UMDR) was observed. HAIs were caused by K. pneumoniae (n = 51/54.3%), E. coli (n = 41/43.6%), or both (n = 2/2.1%), producing ESBL (96%) or carbapenemases (4%). Prior colonization (n = 14/16%) corresponded to seven Kp-CARB and seven Ec/Kp-ESBL. The worrying prevalence of patients acquiring HAIs by Ec/Kp-ESBL/CARB, associated with the estimated rates of those already colonized at admission, highlights a relevant role for LTCFs as a reservoir of Ec/Kp-ESBL/CARB. Epidemiological surveillance should be extended to the national level, and colonization screening at LTCF admission implemented systematically.

Dynamized Aloysia Polystachya (Griseb.) Essential Oil: A Promising Antimicrobial Product

BACKGROUND

 Compounds from vegetal matter have therapeutic potential to control highly prevalent microorganisms that are resistant to commonly used antimicrobial drugs. Dynamization of compounds can either maintain or improve their therapeutic effects, and make their use safer, especially those compounds whose therapeutic dose is close to the toxic limit. Aloysia polystachya (Griseb.) stands out among aromatic plants with antimicrobial potential.

OBJECTIVE

 The aim of this study was to evaluate the antimicrobial activity of dynamized and crude forms of A. polystachya essential oil against Candida albicans, Escherichia coli and Staphylococcus aureus.

METHODS

 Essential oil was extracted from A. polystachya dry leaves, solubilized, and dynamized at 1 cH potency as recommended by the Brazilian Homeopathic Pharmacopoeia. Antimicrobial activity against C. albicans, E. coli and S. aureus of the samples was assayed using the plate microdilution method.

RESULTS

 Dynamized A. polystachya essential oil at the concentration of 1 μg/mL inhibited the growth of all the microbial species analyzed. The minimum inhibitory concentration of dynamized essential oil was smaller than crude essential oil for S. aureus, E. coli and C. albicans.

CONCLUSION

 It is reported for the first time that A. polystachya dynamized essential oil can effectively suppress microbial growth, and it is a promising adjuvant to treat infections with pathogenic S. aureus, E. coli and C. albicans.

Inactivation of Bacteria and Residual Antimicrobials in Hospital Wastewater by Ozone Treatment

The emergence and spread of antimicrobial resistance (AMR) has become a persistent problem globally. In this study, an ozone treatment facility was established for an advanced hospital wastewater treatment in a core hospital facility in an urban area in Japan to evaluate the inactivation of antimicrobial-resistant bacteria and antimicrobials. Metagenomic DNA-seq analysis and the isolation of potential extended-spectrum β-lactamase (ESBL)-producing bacteria suggested that ozone exposure for at least 20 min is required for the adequate inactivation of DNA and ESBL-producing bacteria. Escherichia coli and Klebsiella species were markedly susceptible to 20-min ozone exposure, whereas Raoultella ornithinolytica and Pseudomonas putida were isolated even after an 80-min exposure. These ozone-resistant bacteria might play a pivotal role as AMR reservoirs in the environment. Nine antimicrobials (ampicillin, cefdinir, cefpodoxime, ciprofloxacin, levofloxacin, clarithromycin, chlortetracycline, minocycline, and vancomycin) were detected at 373 ng/L to 27 μg/L in the hospital wastewater, and these were removed (96–100% removal) after a 40-min treatment. These results facilitate a comprehensive understanding of the AMR risk posed by hospital wastewater and provides insights for devising strategies to eliminate or mitigate the burden of antimicrobial-resistant bacteria and the flow of antimicrobials into the environment. To the best of our knowledge, this is the first report on the implementation of a batch-type, plant-scale ozone treatment system in a hospital facility to execute and evaluate the inactivation of drug-resistant bacteria and antimicrobials.

Antibiotic Use in Livestock and Residues in Food-A Public Health Threat: A Review

The usage of antibiotics has been, and remains, a topic of utmost importance; on the one hand, for animal breeders, and on the other hand, for food safety. Although many countries have established strict rules for using antibiotics in animal husbandry for the food industry, their misuse and irregularities in compliance with withdrawal periods are still identified. In addition to animal-origin foods that may cause antibiotic residue problems, more and more non-animal-origin foods with this type of non-compliance are identified. In this context, we aim to summarize the available information regarding the presence of antibiotic residues in food products, obtained in various parts of the world, as well as the impact of consumption of food with antibiotic residues on consumer health. We also aim to present the methods of analysis that are currently used to determine antibiotic residues in food, as well as methods that are characterized by the speed of obtaining results or by the possibility of identifying very small amounts of residues.

Absinthe against multi-drug resistant bacterial pathogens? A recent update on the antibacterial effects of Artemisia compounds

The widespread misuse of antibiotics leads to a rapid development of multi-drug resistant (MDR) bacterial pathogens all over the globe, resulting in serious difficulties when treating infectious diseases. Possible solutions are not limited to the development of novel synthetic antibiotics but extend to application of plant-derived products either alone or in combination with common antibiotics. The aim of this actual review was to survey the literature from the past 10 years regarding the antibacterial effects of distinct Artemisia species including Artemisia absinthiae constituting an integral component of the Absinthe drink. We further explored the synergistic antibacterial effects of the Artemisia plant products with established antibiotics. The survey portrays the Artemisia derived compounds as potent antibacterial agents that can even restore the efficacy of antibiotics against MDR bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA) and MDR Escherichia coli. This, in turn, is presumably triggered in part by the interaction of the Artemisia ingredients with the efflux pumps of MDR bacteria. In conclusion, biologically active molecules in Artemisia plants enhance the antibiotic susceptibility of resistant bacteria, which provide promising future therapeutic strategies to combat MDR bacterial pathogens.

Methodology for laboratory-based antimicrobial resistance surveillance in animals

Antimicrobial resistance (AMR) is a crucial and emerging multifactorial “One Health” problem involving human and animal health, agriculture, aquaculture, and environment; and posing a potential public health hazard globally. The containment of AMR justifies effective surveillance programs to explicate the magnitude of the problem across the contributing sectors. Laboratory-based AMR testing and characterization is the key component of an AMR surveillance program. An AMR surveillance program should have a “top management” for fund mobilization, planning, formulating, and multilateral coordinating of the surveillance activities. The top management should identify competent participating laboratories to form a network comprising a reference laboratory and an adequate number of sentinel laboratories. The responsibilities of the reference laboratory include the development of standardized test methods for ensuring quality and homogeneity of surveillance activities, providing training to the laboratory personnel, and in-depth AMR characterization. The sentinel laboratories will take the responsibilities of receiving samples, isolation and identification of microbes, and initial AMR characterization. The sentinel laboratories will use simple antimicrobial susceptibility test (AST) methods such as disk diffusion tests, whereas the reference laboratories should use automated quantitative AST methods as well as advanced molecular methods to explicit AMR emergence mechanisms. Standard guidelines set by Clinical Laboratory Standards Institute or the European Committee on Antimicrobial Susceptibility Testing, should be followed to bring about conformity and harmonization in the AST procedures. AMR surveillance program in animals is eventually similar to that in human health with the exception is that veterinary antibiotics and veterinary pathogens should be given preference here. Hence, the review study was envisaged to look deep into the structure of the AMR surveillance program with significance on laboratory-based AMR testing and characterization methods.

Microbiology laboratories involved in disease and antimicrobial resistance surveillance: Strengths and challenges of the central African states

Laboratory systems have been largely neglected on the margins of health systems in Africa. However, since the 2000s, many African countries have benefited from massive investments to strengthen laboratory capacities through projects fighting priority diseases (HIV/AIDS, tuberculosis, malaria). This review examined the laboratory capacities of the Economic Community of Central African States (ECCAS). Online research using specific terms was carried out. Studies published between 2000 and 2021 on the role of the laboratory in disease and antimicrobial resistance surveillance in the 11 ECCAS countries were considered. The number of human and animal health laboratories meeting international standards was very low in the sub-region. There were only seven International Organization for Standardization (ISO) 15189-accredited human health laboratories, with five in Cameroon and two in Rwanda. There were five high biosafety level (BSL) laboratories (one BSL3 laboratory each in Cameroon, the Central African Republic, Democratic Republic of Congo and the Republic of Congo, and one BSL4 laboratory in Gabon) and three ISO 17025-accredited laboratories in the ECCAS sub-region. Only six countries currently have whole-genome sequencing devices, which is insufficient for a sub-region as large and populous as ECCAS. Yet, a plethora of pathogens, particularly haemorrhagic viruses, are endemic in these countries. The need for laboratory capacity strengthening following a One Health approach is imperative. Since emerging and re-emerging zoonotic infectious diseases are projected to triple in frequency over the next 50 years and given the inextricable link between human and animal health, actors in the two health sectors must collaborate to preserve world health.