Antimicrobial Resistance In Bacterial Pathogens Research Articles

Synthesis of Ag/NiFe2O4 doped multiwalled carbon nanotube for antibiotic removal from water

Antibiotics impose severe impacts on humans and the ambient water environment by creating antimicrobial resistance in bacterial pathogens; therefore, there exists an urgent need to develop sustainable and efficient adsorbents for the removal of these contaminants from the water. To this goal, silver/nickel ferrite-doped multiwalled carbon nanotubes (Ag/NiFe2O4 doped MWCNTs) were prepared as functional integrated adsorbent material for antibiotic removal from water. The TEM results showed that Ag/NiFe2O4 species were dispersed on the surface of MWCNTs through the available functional groups on their surface. The introduction of Ag/NiFe2O4 nanocomposite onto the MWCNTs efficiently improved the adsorption capacity for ciprofloxacin. The maximum adsorption capacity is estimated to be 26.45 mg/g. The results indicated a higher adsorptive capacity for the produced ternary sample compared to pristine MWCNTs, Ag/NiFe2O4, or NiFe2O4/MWCNTs binary systems. The adsorption capacity for ciprofloxacin in the samples was evidently dependent on the MWCNTs dose, solution pH, adsorbate dose, and temperature. Ag/NiFe2O4 doped MWCNTs (65 % w/w) were able to remove ∼95 % of ciprofloxacin in the testing solution even after being reclaimed for 4 times following the Langmuir isotherm model in the endothermic manner. Also, the adsorption of CIP by the nanocomposite demonstrates a pseudo-second-order model. These promising results open a pathway for efficient carbon materials to be replaced by conventional adsorbents to remove antibiotics from water.

Analysis of Antimicrobial Resistance in Bacterial Pathogens Recovered from Food and Human Sources: Insights from 639,087 Bacterial Whole-Genome Sequences in the NCBI Pathogen Detection Database.

Understanding the role of foods in the emergence and spread of antimicrobial resistance necessitates the initial documentation of antibiotic resistance genes within bacterial species found in foods. Here, the NCBI Pathogen Detection database was used to query antimicrobial resistance gene prevalence in foodborne and human clinical bacterial isolates. Of the 1,843,630 sequence entries, 639,087 (34.7%) were assigned to foodborne or human clinical sources with 147,788 (23.14%) from food and 427,614 (76.88%) from humans. The majority of foodborne isolates were either Salmonella (47.88%), Campylobacter (23.03%), Escherichia (11.79%), or Listeria (11.3%), and the remaining 6% belonged to 20 other genera. Most foodborne isolates were from meat/poultry (95,251 or 64.45%), followed by multi-product mixed food sources (29,892 or 20.23%) and fish/seafood (6503 or 4.4%); however, the most prominent isolation source varied depending on the genus/species. Resistance gene carriage also varied depending on isolation source and genus/species. Of note, Klebsiella pneumoniae and Enterobacter spp. carried larger proportions of the quinolone resistance gene qnrS and some clinically relevant beta-lactam resistance genes in comparison to Salmonella and Escherichia coli. The prevalence of mec in S. aureus did not significantly differ between meat/poultry and multi-product sources relative to clinical sources, whereas this resistance was rare in isolates from dairy sources. The proportion of biocide resistance in Bacillus and Escherichia was significantly higher in clinical isolates compared to many foodborne sources but significantly lower in clinical Listeria compared to foodborne Listeria. This work exposes the gaps in current publicly available sequence data repositories, which are largely composed of clinical isolates and are biased towards specific highly abundant pathogenic species. We also highlight the importance of requiring and curating metadata on sequence submission to not only ensure correct information and data interpretation but also foster efficient analysis, sharing, and collaboration. To effectively monitor resistance carriage in food production, additional work on sequencing and characterizing AMR carriage in common commensal foodborne bacteria is critical.

Structural analysis of resistance-nodulation cell division transporters.

SUMMARYInfectious bacteria have both intrinsic and acquired mechanisms to combat harmful biocides that enter the cell. Through adaptive pressures, many of these pathogens have become resistant to many, if not all, of the current antibiotics used today to treat these often deadly infections. One prominent mechanism is the upregulation of efflux systems, especially the resistance-nodulation-cell division class of exporters. These tripartite systems consist of an inner membrane transporter coupled with a periplasmic adaptor protein and an outer membrane channel to efficiently transport a diverse array of substrates from inside the cell to the extracellular space. Detailed mechanistic insight into how these inner membrane transporters recognize and shuttle their substrates can ultimately inform both new antibiotic and efflux pump inhibitor design. This review examines the structural basis of substrate recognition of these pumps and the molecular mechanisms underlying multidrug extrusion, which in turn mediate antimicrobial resistance in bacterial pathogens.

In vitro and in silico studies of enterobactin-inspired Ciprofloxacin and Fosfomycin first generation conjugates on the antibiotic resistant E. coli OQ866153

BackgroundThe emergence of antimicrobial resistance in bacterial pathogens is a growing concern worldwide due to its impact on the treatment of bacterial infections. The "Trojan Horse" strategy has been proposed as a potential solution to overcome drug resistance caused by permeability issues.ObjectiveThe objective of our research was to investigate the bactericidal activity and mechanism of action of the "Trojan Horse" strategy using enterobactin conjugated with Ciprofloxacin and Fosfomycin against the antibiotic-resistant Escherichia coli strain OQ866153.MethodologyEnterobactin, a mixed ligand of E. coli OQ866153, was conjugated with Ciprofloxacin and Fosfomycin individually to aid active absorption via specific enterobactin binding proteins (FepABCDG). The effectiveness of the conjugates was assessed by measuring their bactericidal activity against E. coli OQ866153, as well as their ability to inhibit DNA gyrase enzyme and biofilm formation.ResultsThe Fe+3-enterobactin-Ciprofloxacin conjugate effectively inhibited the DNA gyrase enzyme (Docking score = -8.597 kcal/mol) and resulted in a lower concentration (25 μg/ml) required to eliminate supercoiled DNA plasmids compared to the parent drug (35 μg/ml; Docking score = -6.264 kcal/mol). The Fe+3-Enterobactin-Fosfomycin conjugate showed a higher inhibition percentage (100%) of biofilm formation compared to Fosfomycin (21.58%) at a concentration of 2 mg/ml, with docking scores of -5.481 and -3.756 kcal/mol against UDP-N acetylglucosamine 1-carboxyvinyltransferase MurA.ConclusionThe findings of this study suggest that the "Trojan Horse" strategy using enterobactin conjugated with Ciprofloxacin and Fosfomycin can effectively overcome permeability issues caused by efflux proteins and enhance the bactericidal activity of these drugs against antibiotic-resistant strains of E. coli.

Retrospective analysis of antimicrobial resistance in bacterial pathogens from pet rabbits in Hong Kong, 2019-2022.

Antimicrobial resistance (AMR) is a growing threat to human and animal health. Data are limited on the prevalence of resistant bacteria in pet rabbits. Therefore, we aimed to identify prevalent bacterial infections and AMR profiles among pet rabbits in Hong Kong (HK). Our search of the CityU Veterinary Diagnostic Laboratory (VDL) database found 301 cases of pet rabbits submitted for bacteriologic and antimicrobial susceptibility testing by veterinarians at 20 exotic veterinary clinics across HK between 2019 and 2022. The rabbits were of 8 different breeds and had a median age of 6.5 y, with 54.8% males, 40.2% females, and 5% unspecified. Of the 301 samples received, 168 (55.8%) had positive bacterial growth; 125 (74.4%) had single bacterial isolates, and 43 (25.6%) had mixed cultures. Cultures included Enterococcus faecalis (21.3%) as the most frequently isolated gram-positive bacterium, followed by Streptococcus intermedius (12.5%), and Staphylococcus aureus (11.3%). The most frequently isolated gram-negative bacteria were Pseudomonas aeruginosa (18.1%), followed by Escherichia coli (8.3%), Pasteurella multocida (6.9%), and Klebsiella pneumoniae (4.2%). Approximately 83% of the isolates had acquired resistance to at least one antimicrobial agent, and 49.4% were multidrug-resistant. The isolated bacteria had high levels of resistance to penicillin (69.8%), clindamycin (47.4%), and doxycycline (46.9%). Our findings highlight the high levels of AMR in bacteria isolated from pet rabbit clinical samples in HK; many of these bacteria are zoonotic and pose a public health threat.

PREVALENCE OF BLATEM, BLASHV, AND BLACTX-M GENES AMONG ESBL-PRODUCING ESCHERICHIA COLI ISOLATED FROM THE BLOOD SAMPLES OF ICUS PATIENTS OF UNIVERSITY HOSPITALS IN SANA'A CITY, YEMEN

Aim and Objective: With the emergence of organisms such as Enterobacteriaceae that produce extended-spectrum β-lactamase (ESBL), which are resistant to multiple medications (multidrug-resistance), concerns about how best to treat infections have significantly increased. The current study examined the molecular features of ESBL in clinical isolates of Escherichia coli that resulted in bloodstream infections as well as the pattern of antibiotic resistance to gather useful data on the infection's epidemiology among Yemeni ICU patients. Subjects and methods: A cross-sectional study was conducted on sepsis patients admitted in intensive care units at four hospitals in Sana'a, Yemen, between January, 2021 and April, 2022. Blood cultures were used on patients suspected of having sepsis. Standard laboratory procedures were then used to isolate and identify possible bacterial infections, and the disk diffusion method was used to test for microbial susceptibility. All strains were tested for Extended Spectrum Beta-Lactamase (ESBL) production using the Modified Double Disc Synergy Test (MDDST). Following analysis, polymerase chain reaction, β-lactamase genes (blaTEM, blaSHV, and blaCTX-M) were identified. Results: The results of the conventional PCR experiment revealed that 33.3% of the blaCTX-M genes, 0.0% of blaSHV, and 100% of blaTEM were present in the strains of ESBL-producing E. coli that were collected. It was discovered that the E. coli isolates' patterns of antibiotic resistance to 23 different antibiotics differed greatly. The bulk of the E. coli isolates were found to be multi-drug resistant (MDR). Furthermore, MDR characteristics were observed in 85% of E. coli isolates. Conclusion: Control and surveillance of antibiotic resistance depend on an understanding of the resistance genes and patterns of antimicrobial resistance of bacterial pathogens within a given geographic area. The current study's findings showed that MDR was very common. According to the current study's findings, TEM was significantly more common than other ESBL gene types. Peer Review History: Received: 7 November 2023; Revised: 12 December; Accepted: 6 January 2024, Available online: 15 January 2024 Academic Editor: Dr. A.A. Mgbahurike, University of Port Harcourt, Nigeria, amaka_mgbahurike@yahoo.com Received file: Reviewer's Comments: Average Peer review marks at initial stage: 6.5/10 Average Peer review marks at publication stage: 8.0/10 Reviewers: Dr. Rola Jadallah, Arab American University, Palestine, rola@aauj.edu Dr. Wadhah Hassan Ali Edrees, Hajja University, Yemen, edress2020@gmail.com

2588. Burden of Mortality and Antimicrobial Resistance of Bacterial Pathogens Associated with Lower Respiratory Tract and Other Thorax Infection in United States in 2019: A Systematic Analysis

Abstract Background Detailed information about the impact of bacterial antimicrobial resistance (AMR) on Lower Respiratory Tract and other thorax Infections (LRTIs) is currently unavailable. It is important to have precise data on bacterial AMR to develop effective programs and policies for controlling AMR and to use antibiotics prudently for optimal treatment of LRTI patients. The primary objective of this research is to present extensive estimates of the mortality due to "bacterial pathogens" and its "AMR" of LRTIs in the United States in 2019. Methods Mortality data associated with bacterial antimicrobial resistance and lower respiratory tract infection (LRTI) pathogens were acquired from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) in 2019. Results In United States, there were 88089 deaths (95% uncertainty interval [UI]: 66909-117145) due to bacterial pathogens in LRIT in 2019. Highest number of deaths observed due to Staphylococcus aureus (34.04%), followed by Streptococcus pneumoniae (18.30%), Pseudomonas aeruginosa (12.48%) in LRTI in 2019. There were 10984 deaths attributed to and 46482 deaths associated with bacterial AMR in LRTI in 2019. Conclusion Bacterial pathogens causing LRTIs are a significant cause of mortality in the United States. Moreover, antimicrobial resistance (AMR) among these pathogens has become a growing concern, exacerbating the burden of LRTI-related deaths. The implementation of such measures, along with the promotion of antimicrobial stewardship, can help to mitigate the impact of LRTI-associated deaths and preserve the effectiveness of available antimicrobial agents for the future. Disclosures All Authors: No reported disclosures

Interpretable machine learning-based decision support for prediction of antibiotic resistance for complicated urinary tract infections

Urinary tract infections are one of the most common bacterial infections worldwide; however, increasing antimicrobial resistance in bacterial pathogens is making it challenging for clinicians to correctly prescribe patients appropriate antibiotics. In this study, we present four interpretable machine learning-based decision support algorithms for predicting antimicrobial resistance. Using electronic health record data from a large cohort of patients diagnosed with potentially complicated UTIs, we demonstrate high predictability of antibiotic resistance across four antibiotics – nitrofurantoin, co-trimoxazole, ciprofloxacin, and levofloxacin. We additionally demonstrate the generalizability of our methods on a separate cohort of patients with uncomplicated UTIs, demonstrating that machine learning-driven approaches can help alleviate the potential of administering non-susceptible treatments, facilitate rapid effective clinical interventions, and enable personalized treatment suggestions. Additionally, these techniques present the benefit of providing model interpretability, explaining the basis for generated predictions.

Building the National Antimicrobial Resistance Surveillance Network in Animals in Greece: A "One Health" Approach.

It is widely accepted that, in order to prevent and control antimicrobial resistance (AMR), surveillance systems across human, animal and environmental sectors need to be integrated, in a One Health approach. Currently, in Europe, there are surveillance networks established only for the human and food sector and, until now, there has been no organized effort to monitor AMR in bacterial pathogens derived from diseased animals in Europe. Since 2017, efforts to fill this gap have taken place by the European Antimicrobial Resistance Surveillance network in a veterinary medicine (EARS-Vet) initiative, included in the EU Joint Action on AMR and Healthcare-Associated Infections (EU-JAMRAI). EARS-Vet is designed to complement and integrate with existing European monitoring systems for AMR as well as constitute a European network of national monitoring systems. As Greece has no national AMR surveillance system for pathogens of animal origin currently in place, in the context of the development of EARS-Vet, an initiative took place for the organization of such a system by competent agencies and other stakeholders. In this article, the steps to organize a first AMR national surveillance network in Greece are presented and a Strengths, Weaknesses, Opportunities, and Threats (SWOT) analysis is performed to present main characteristics of the approach implemented.

Prevalence of ESKAPE Bacteria in Surface Water and Wastewater Sources: Multidrug Resistance and Molecular Characterization, an Updated Review

ESKAPE bacteria represent a group of opportunistic bacterial pathogens that display widespread antimicrobial resistance, including resistance to the last-line antibiotics, thereby posing a significant clinical implication globally. Anthropogenic activities, such as wastewater from hospitals, livestock farms, crop fields, and wastewater treatment plants, contribute to the dissemination of antimicrobial-resistant bacterial pathogens into the environment. Surface water sources, including river waters, act as critical points of discharge for wastewater, pollutants, antibiotic-resistant bacteria (ARB), and antibiotic-resistant genes (ARG). These environmental factors, along with others, facilitate the dissemination and survival of ARBs, as well as promote the exchange of ARGs. Therefore, it is crucial to comprehend the current environmental landscape concerning the prevalence and persistence of resistant bacteria, particularly those belonging to the ESKAPE group. This review aims to provide a comprehensive overview of the current dissemination and characterization of ESKAPE bacteria in surface water and wastewater sources.

Gas Chromatography-Mass Spectroscopy and antibacterial activity of stem bark of Terminalia glaucescens on some multidrug-resistant gram-negative bacteria

Frequent antimicrobial resistance of bacterial pathogens has led to a search for plant origin to synthesize new drugs. Hence, the antibacterial potential of the stem bark part of Terminalia glaucescens plant needs to ascertain. The 162 pure bacteria isolated from the patient’s clinical samples were confirmed using standard procedures to be Escherichia coli (65), Pseudomonas aeruginosa (52), and Klebsiella pneumonia (45). The isolates were tested against seven commonly available antibiotics and the extracts. The identified bark of T. glaucescens was prepared for qualitative analysis using standard methods and also analyzed quantitatively using Gas Chromatography-Mass Spectroscopy (GC-MS). Alkaloid, saponin, flavonoid, steroids, tannin, terpenoid, and phenol were identified. The GC-MS analysis revealed 13 bioactive constituents with Neophytadiene, Squalene, 3, 7, 11, 15-Tetramethyl-2-hexadecen-1-ol and 9-eicosyne as active components. Antibiogram study revealed that most isolates, especially E. coli and P. aeruginosa, were 100% resistant to more than two antibiotics. The antibacterial activity of the stem bark of T. glaucescens was reflected by inhibition zones, ranging from 5.5 mm to 12.5 mm; Escherichia coli had the highest zone of inhibition (12.5 mm). The presence of phytochemicals and bioactive components in this stem bark suggests its effectiveness in treating infections and producing pharmaceutical products.

Predicting antimicrobial resistance of bacterial pathogens using time series analysis.

Antimicrobial resistance (AMR) is arguably one of the major health and economic challenges in our society. A key aspect of tackling AMR is rapid and accurate detection of the emergence and spread of AMR in food animal production, which requires routine AMR surveillance. However, AMR detection can be expensive and time-consuming considering the growth rate of the bacteria and the most commonly used analytical procedures, such as Minimum Inhibitory Concentration (MIC) testing. To mitigate this issue, we utilized machine learning to predict the future AMR burden of bacterial pathogens. We collected pathogen and antimicrobial data from >600 farms in the United States from 2010 to 2021 to generate AMR time series data. Our prediction focused on five bacterial pathogens (Escherichia coli, Streptococcus suis, Salmonella sp., Pasteurella multocida, and Bordetella bronchiseptica). We found that Seasonal Auto-Regressive Integrated Moving Average (SARIMA) outperformed five baselines, including Auto-Regressive Moving Average (ARMA) and Auto-Regressive Integrated Moving Average (ARIMA). We hope this study provides valuable tools to predict the AMR burden not only of the pathogens assessed in this study but also of other bacterial pathogens.

Molecular mechanisms of biofilm resistance against antibiotics

Biofilms are immobile communities of microbes attached to biotic an abiotic surfaces and are embedded inside a self-produced cement-like extracellular polymeric substances. The resistance of biofilms against commonly used drugs has been implicated in the pathogenesis of various bacterial infections under medical and veterinary settings which normally cannot be eradicated by antibiotics. Biofilms are characterized by the ability to evade not only the antibiotic effects but also the host immune system clearance. Currently the most worrisome aspect of global human health is the rise and spread of antimicrobial resistance in bacterial pathogens and this crisis got deepened by the emergence of antimicrobial resistance of bacterial biofilms. Different antibiotic resistance mechanisms, processes by which a target pathogen curtails the interaction between an antimicrobial agent and its intended target molecules, adopted by biofilms have been discussed in this review. Different antibiotic resistance mechanisms are employed by the biofilms depending on the species of the bacteria, growth conditions, and the antibiotic involved. Commonly, the role of biofilm matrix polysaccharides, antibiotic-modifying or degrading enzymes, extracellular DNA, hypoxic conditions, presence of efflux pumps, quorum sensing, horizontal gene transfer, mutation frequency, etc. have been implicated in antibiotic resistance of biofilms. This review also discusses different approaches of overcoming biofilm infections or biofilm resistance. However, it is pertinent to mention that since no new class of antibiotics have been approved in last four decades there is the need of greater understanding of biofilm-associated antibiotic resistance to effectively utilise the therapeutic value of the existing antibiotics. Although a number of anti-biofilm strategies have been put forward as discussed in this review, they are still in nascent stage and need to undergo clinical trials to reach the commercial market.

Multivalent human antibody-centyrin fusion protein to prevent and treat Staphylococcus aureus infections

Treating and preventing infections by antimicrobial-resistant bacterial pathogens is a worldwide problem.Pathogens such as Staphylococcus aureus produce an array of virulence determinants, makingit difficult to identify single targets for the development of vaccines or monoclonal therapies. We described a human-derived anti-S.aureus monoclonal antibody (mAb)-centyrin fusion protein ("mAbtyrin") that simultaneously targets multiple bacterial adhesins, resists proteolysis by bacterial protease GluV8, avoids Fc engagement by S.aureus IgG-binding proteins SpA and Sbi, and neutralizes pore-forming leukocidins via fusion with anti-toxin centyrins, while maintaining Fc- and complement-mediated functions. Compared with the parental mAb, mAbtyrin protected human phagocytes and boosted phagocyte-mediated killing. The mAbtyrin also reduced pathology, reduced bacterial burden,and protected from different types of infections in preclinical animal models. Finally, mAbtyrin synergized with vancomycin, enhancing pathogen clearance in an animal model of bacteremia. Altogether, these data establish the potential of multivalent mAbs for treating and preventing S.aureus diseases.

Deciphering the genetic network and programmed regulation of antimicrobial resistance in bacterial pathogens.

Antimicrobial resistance (AMR) in bacteria is an important global health problem affecting humans, animals, and the environment. AMR is considered as one of the major components in the "global one health". Misuse/overuse of antibiotics in any one of the segments can impact the integrity of the others. In the presence of antibiotic selective pressure, bacteria tend to develop several defense mechanisms, which include structural changes of the bacterial outer membrane, enzymatic processes, gene upregulation, mutations, adaptive resistance, and biofilm formation. Several components of mobile genetic elements (MGEs) play an important role in the dissemination of AMR. Each one of these components has a specific function that lasts long, irrespective of any antibiotic pressure. Integrative and conjugative elements (ICEs), insertion sequence elements (ISs), and transposons carry the antimicrobial resistance genes (ARGs) on different genetic backbones. Successful transfer of ARGs depends on the class of plasmids, regulons, ISs proximity, and type of recombination systems. Additionally, phage-bacterial networks play a major role in the transmission of ARGs, especially in bacteria from the environment and foods of animal origin. Several other functional attributes of bacteria also get successfully modified to acquire ARGs. These include efflux pumps, toxin-antitoxin systems, regulatory small RNAs, guanosine pentaphosphate signaling, quorum sensing, two-component system, and clustered regularly interspaced short palindromic repeats (CRISPR) systems. The metabolic and virulence state of bacteria is also associated with a range of genetic and phenotypic resistance mechanisms. In spite of the availability of a considerable information on AMR, the network associations between selection pressures and several of the components mentioned above are poorly understood. Understanding how a pathogen resists and regulates the ARGs in response to antimicrobials can help in controlling the development of resistance. Here, we provide an overview of the importance of genetic network and regulation of AMR in bacterial pathogens.

Efficacy of phage therapy in preclinical models of bacterial infection: a systematic review and meta-analysis

Antimicrobial resistance of bacterial pathogens is an increasing clinical problem and alternative approaches to antibiotic chemotherapy are needed. One of these approaches is the use of lytic bacterial viruses known as phage therapy. We aimed to assess the efficacy of phage therapy in preclinical animal models of bacterial infection. In this systematic review and meta-analysis, MEDLINE/Ovid, Embase/Ovid, CINAHL/EbscoHOST, Web of Science/Wiley, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Google Scholar were searched from inception to Sept 30, 2021. Studies assessing phage efficacy in animal models were included. Only studies that assessed the efficacy of phage therapy in treating established bacterial infections in terms of survival and bacterial abundance or density were included. Studies reporting only in-vitro or ex-vivo results and those with incomplete information were excluded. Risk-of-bias assessment was performed using the Systematic Review Centre for Laboratory Animal Experimentation tool. The main endpoints were animal survival and tissue bacterial burden, which were reported using pooled odds ratios (ORs) and mean differences with random-effects models. The I2 measure and its 95% CI were also calculated. This study is registered with PROSPERO, CRD42022311309. Of the 5084 references screened, 124 studies fulfilled the selection criteria. Risk of bias was high for 70 (56%) of the 124 included studies; therefore, only studies classified as having a low-to-moderate risk of bias were considered for quantitative data synthesis (n=32). Phage therapy was associated with significantly improved survival at 24 h in systemic infection models (OR 0·08 [95% CI 0·03 to 0·20]; I2=55% [95% CI 8 to 77]), skin infection (OR 0·08 [0·04 to 0·19]; I2 = 0% [0 to 79]), and pneumonia models (OR 0·13 [0·06 to 0·31]; I2=0% [0 to 68]) when compared with placebo. Animals with skin infections (mean difference -2·66 [95% CI -3·17 to -2·16]; I2 = 95% [90 to 96]) and those with pneumonia (mean difference -3·35 [-6·00 to -0·69]; I2 = 99% [98 to 99]) treated with phage therapy had significantly lower tissue bacterial loads at 5 ± 2 days of follow-up compared with placebo. Phage therapy significantly improved animal survival and reduced organ bacterial loads compared with placebo in preclinical animal models. However, high heterogeneity was observed in some comparisons. More evidence is needed to identify the factors influencing phage therapy performance to improve future clinical application. Swiss National Foundation and Swiss Heart Foundation.

Antimicrobial resistance status of selected bacteria isolated from animal source foods and feed in Ethiopia

Antimicrobial resistance (AMR) of major food-borne pathogens has become an increasing public health problem worldwide. A cross-sectional study was conducted from August 2019 to July 2021 in high-potential meat and dairy products and commercial animal feed supply chain areas of Ethiopia. The objectives of the study was assessing AMR profile of target bacterial pathogens isolated from animal sources foods (ASFs) and feed. A total of 642 ASFs and feed samples collected from selected sampling sites were examined at the microbiology laboratory of animal products, veterinary drugs, and feed quality assessment center. Bacterial identification and antimicrobial susceptibility test (AST) were conducted using an automated Vitek 2 XL compact system. Out of 642 investigated samples, 24 different genera and 59 species of bacteria were identified. A total of 185 samples were positive for target bacteria of Staphylococcus aureus, Escherichia coli, and Salmonella Species. The AST results showed AMR of target bacteria isolates against some of the tested antimicrobials. Of these, 83%, 55%, and 92% isolates of Staphylococcus aureus, Escherichia coli, and Salmonella Species, showed high level of AMR to Benzylpenicillin, Tetracycline, and Cefalexin/Gentamicin, respectively. The target bacteria isolated from ASFs and feed demonstrated multidrug resistance against some of the tested antimicrobials having public and veterinary importance. This reflects that ASFs and feed could serve as one of the sources for the spread and transmission of antimicrobial-resistant bacterial pathogens. Hence, there is a need for improving hygiene and sanitation practices along the ASFs and feed supply chains. Besides raising community awareness about the risks of AMR, emphasis on the rational use of antimicrobials in animal health practice and further investigations on AMR are recommended.

Antimicrobial resistance of bacterial pathogens isolated from the infections of post maxillofacial surgery.

Inappropriate antibiotic prescriptions contributed to a global issue of antimicrobial resistance. This study aimed to assess the prevalence of bacterial pathogens and antimicrobial resistance isolated from maxillofacial infections (MIs). Two hundred and twenty-two patients with different MIs were included in this study. Swab samples were taken from the site of infections. Samples were cultured, and isolated bacteria were identified using various biochemical tests. Antimicrobial resistance patterns of isolates were assessed by the disk diffusion method. The mean age of the patients was 50.8 years. The male-to-female ratio was 127/95 (P<0.05). Smoking and alcohol consumption were found in 60.36% and 37.38% of patients, respectively. Most patients had a ≤1-week infection duration (P<0.05). Abscess lesion was the most predominant infection type (P<0.05). The prevalence of aerobic bacteria among abscess, pus localization, and deep facial infections was 59.33%, 64.28%, and 46.66%, respectively. The prevalence of anaerobic bacteria among abscess, pus localization, and deep facial infections was 40.66%, 23.80%, and 53.33%, respectively. Staphylococcus aureus (10.36%) and Prevotella buccalis (8.55%) had the uppermost distribution amongst all examined samples. Isolated bacteria exhibited the uppermost resistance rate toward penicillin (65.76%), tetracycline (61.26%), gentamicin (58.10%), and ampicillin (57.65%) antimicrobials. The lowest resistance rate was obtained for linezolid (25.67%), ceftriaxone (31.08%), and azithromycin (31.08%) antimicrobials. Linezolid, ceftriaxone, and azithromycin had effective antimicrobial activities toward bacteria isolated from MIs. Therefore, cautious antibiotic prescription might decrease the prevalence of antimicrobial resistance in dental and maxillofacial infections.

Impact of Bacterial Infections and Antibiotic Use on Hospitalized COVID-19 Patients: An Emerging Infections Network Survey

The SARS-CoV-2 pandemic has had a significant impact on the United States healthcare system. This is exacerbated by antimicrobial-resistant bacterial pathogens endemic to healthcare settings. Respiratory viral infections are known to predispose patients to bacterial infections, which were a major contributor to mortality in previous pandemics. This study’s goal was to gain an understanding of bacterial infections in hospitalized COVID-19 patients. A case form for COVID-19 patients with bacterial infections was developed and sent to clinicians on the Emerging Infections Network listserv. The case form included 22 questions on patient demographics, COVID-19 and bacterial infection and treatment, and patient outcome. One hundred and nine patient cases were collected and analyzed. The majority of patients (59.6%) were critically ill, and 66.9% of patients were diagnosed with sepsis. Empiric and directed antibiotics were administered to 81.6% and 94.5% of patients, respectively. Thirty-one infections were not resolved with antibiotics, and of those patients, 74.2% died. Unresolved bacterial infections were found to be a significant contributor to mortality in this case series. These bacterial infections can most likely be attributed to long hospital stays and exposure to nosocomial pathogens. Thus, unresolved nosocomial bacterial infections warrant additional attention during future events where there is a strain on the US healthcare system.

Review and Analysis of National Monitoring Systems for Antimicrobial Resistance in Animal Bacterial Pathogens in Europe: A Basis for the Development of the European Antimicrobial Resistance Surveillance Network in Veterinary Medicine (EARS-Vet).

The monitoring of antimicrobial resistance (AMR) in bacterial pathogens of animals is not currently coordinated at European level. To fill this gap, experts of the European Union Joint Action on Antimicrobial Resistance and Healthcare Associated Infections (EU-JAMRAI) recommended building the European Antimicrobial Resistance Surveillance network in Veterinary medicine (EARS-Vet). In this study, we (i) identified national monitoring systems for AMR in bacterial pathogens of animals (both companion and food-producing) among 27 countries affiliated to EU-JAMRAI, (ii) described their structures and operations, and (iii) analyzed their respective strengths, weaknesses, opportunities and threats (SWOT). Twelve countries reported having at least one national monitoring system in place, representing an opportunity to launch EARS-Vet, but highlighting important gaps in AMR data generation in Europe. In total, 15 national monitoring systems from 11 countries were described and analyzed. They displayed diverse structures and operations, but most of them shared common weaknesses (e.g., data management and representativeness) and common threats (e.g., economic vulnerability and data access), which could be addressed collectively under EARS-Vet. This work generated useful information to countries planning to build or improve their system, by learning from others’ experience. It also enabled to advance on a pragmatic harmonization strategy: EARS-Vet shall follow the European Committee on Antimicrobial Susceptibility Testing (EUCAST) standards, collect quantitative data and interpret AMR data using epidemiological cut-off values.