Levels Of Antibiotic Resistance Research Articles

Green synthesis of silver nanoparticles using Acroptilon repens aqueous extract and their antibacterial efficacy against multidrug-resistant Acinetobacter baumannii.

Acinetobacter baumannii is a critical pathogen associated with hospital-acquired infections, particularly in burn and intensive care unit (ICU) patients, and is notorious for its high level of antibiotic resistance. This study aims to evaluate the antibacterial potential of silver nanoparticles (AgNPs) synthesized using Acroptilon repens extract as a promising alternative treatment for combating multidrug-resistant A. baumannii. Twelve clinical isolates of A. baumannii were identified through biochemical testing. Antibiotic susceptibility testing using the Kirby-Bauer disk diffusion method revealed universal resistance to ceftazidime, amikacin, imipenem, gentamicin, ciprofloxacin, and piperacillin-tazobactam, while all isolates remained sensitive to colistin (p ≤ 0.05). AgNPs were synthesized using A. repens extract and characterized through transmission electron microscopy (TEM), scanning electron microscopy (SEM), particle size analysis (PSA), UV-Vis spectroscopy, X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FT-IR). TEM analysis showed that the AgNPs had a spherical morphology with an average particle size of approximately 30nm, while SEM confirmed their spherical shape and size distribution, ranging from 10 to 130nm, with a mean size of 38.89nm. UV-Vis spectroscopy confirmed the successful formation of AgNPs, indicated by a distinct broad absorption peak between 400 and 480nm. XRD analysis validated the crystalline nature of the nanoparticles, with characteristic peaks at 2θ values of 38.21°, 46.28°, 64.57°, and 77.49°, corresponding to the (111), (200), (220), and (311) planes of face-centered cubic (fcc) silver. Antibacterial activity was evaluated by determining the minimum inhibitory concentration (MIC), which ranged from 50 to 400µg/mL. The highest inhibitory activity was observed at 400µg/mL. Gene expression analysis using quantitative real-time PCR (qRT-PCR) demonstrated downregulation of the oprD and carO porin genes following AgNP treatment. However, these reductions were not statistically significant (p = 0.302 and p = 0.198, respectively). AgNPs synthesized from A. repens demonstrated strong antibacterial activity against multidrug-resistant A. baumannii. While downregulation of porin genes was observed, further investigation is required to elucidate the underlying mechanisms of action and assess their potential clinical applications. These findings support the potential of AgNPs as an alternative therapeutic strategy for addressing A. baumannii infections resistant to conventional antibiotics.

Evolution of the microbiota of wound infections in military personnel during the full-scale russian invasion: a retrospective cohort study (2022–2024)

Background. Infectious complications remain one of the main causes of mortality and morbidity in blast injury among military personnel. The prevalence of infectious complications in blast injury reaches 35 %, and often the causative agents of such infections are multidrug-resistant microorganisms. The purpose was to analyze the dynamics of causative agents of wound infections in military personnel during the full-scale russian invasion. Materials and methods. We conducted a retrospective cohort study of servicemen who were injured during hostilities and were treated at the Feofaniya Clinical Hospital from March 2022 to March 2024. Wound culture was mandatory for study inclusion. Samples were taken from wounds with signs of inflammation, and microbiological testing was carried out in the laboratory of Feofaniya Clinical Hospital. Cultures were conducted in accordance with standard methods of medical microbiology. The disc diffusion method was used to determine the sensitivity of isolates to antimicrobial drugs. Results. The study included 478 servicemen (mean age of 36.60 ± 0.42 years, range 18–67, 99.6 % were males) who have had 1441 wound cultures, and 2483 isolates were identified. No pathogen was detected in 289 cases (11.63 %), fungal isolates were detected in 59 (2.38 %) cases, and the remaining isolates (2135; 85.98 %) were found to be bacterial. Gram-negative flora predominated among them — 80.2 % (95% confidence interval (CI) 78.4–81.8), while Gram-positive flora accounted for 19.8 % (95% CI 18.2–21.6), p < 0.001. The most common pathogens were Klebsiella pneumoniae (22.8 %; 95% CI 21.2–24.5), Acinetobacter baumannii (20 %; 95% CI 18.5–21.6), Pseudomonas aeruginosa (13.6 %; 95% CI 12.3–14.9) and Enterococcus spp. (6.2 %; 95% CI 5.3–7.2). Other pathogens were observed with a proportion of < 5 %. Monomicrobial cultures accounted for 50.5 % (95% CI 47.8–53.3), two isolates were found in 34.0 % (95% CI 31.4–36.6), three isolates — in 12.7 % (95% CI 10.9–14.5), four isolates — in 2.2 % (95% CI 1.4–3.0) and five isolates — in 0.6 % (95% CI 0.3–1.1) of all cultures. There was a significant level of antibiotic resistance — 99.7 % of Klebsiella pneumoniae isolates were multidrug-resistant. Conclusions. Wound infection in blast injury is characterized by a significant predominance of Gram-negative microflora with a high prevalence of antibiotic resistance. Polymicrobial flora was identified in half of the cases of wound infection.

Dissemination of antibiotic-resistant bacteria associated with microplastics collected from Monastir and Mahdia coasts (Tunisia)

The exponential use of plastics and their recalcitrant nature leads to their significant accumulation in the environment. The occurrence of plastic wastes is considered as a serious environmental problem. Additionally, plastic wastes can break down into smaller pieces called microplastics (MPs), leading to further interactions with the environment and living organisms. In this study, sixty-six strains were isolated from microplastic particles collected on different coastal areas of Monastir and Mahdia (Tunisia). The different bacterial isolates were identified according to some biochemical tests such as catalase, oxidase, and were subjected to molecular characterization. Amplification of the internal transcribed spacer (ITS) revealed the presence of 31 ITS haplotypes. The partial sequencing of the 16S ribosomal DNA of representative strains was analyzed. The majority of bacterial isolates (84.31%) belonged to Gamma-proteobacteria (84.78 %), while the remaining isolates were affiliated to Firmicutes (15.21 %). The microplastic-associated bacterial isolates belonged to 10 genera, namely Acinetobacter, Pseudomonas, Bacillus, Staphylococcus, Shewanella, Aeromonas, Vibrio, Stutzerimonas, Exiguobacterium, Enterobacter. Among the well-represented Acinetobacter genus, the most common species identified was Acinetobacter johnsonii. Susceptibility patterns of these strains were studied against 21 antibiotics commonly used in Tunisia. A high level of antibiotic resistance was observed for Penicillin G (97.82%) and Temocillin (86.95%). S26 strain presented the highest multidrug resistance with a multiple antibiotic resistance (MAR) index of 0.71.

Analysis on characteristics and multilocus sequence typing of Clostridium perfringens in western China.

The objective of this study was to identify and analyse the distribution characteristics, toxin genotyping and antimicrobial susceptibility of Clostridium perfringens and to investigate its resistance mechanisms and genetic characteristics. The MICs of various antibiotics against C. perfringens were determined using the agar dilution method, and resistance genes and toxin genotypes were detected by PCR. Genetic relationships were analysed using MLST. WGS was conducted on the DNB system and PacBio platforms. Analysis of 36 strains of C. perfringens revealed that the major toxin types were types C and F, with 86.1% of the strains isolated from bile samples. Of these, 30.6% of the strains exhibited MDR, with resistance rates of 75.0%, 52.8% and 52.8% for penicillin, clindamycin and ampicillin, respectively; however, no resistance to metronidazole and carbapenems was observed. MLST analysis identified 29 STs, including 14 novel types. ST221 and ST498 were the dominant types. The WGS revealed that the most prevalent virulence factors are plc (100.0%), nagH (100.0%), colA (100.0%), nanJ (100.0%), entB (100%), nanH (97.0%), entA (97.0%) and nanI (90.9%). Among these factors, the primary determinants of tetracycline resistance are tetA (66.7%) and tetB (78.8%), which represent the most frequently detected antibiotic resistance genes. This study indicates that the infection rate of C. perfringens is relatively high, with the majority of isolated strains exhibiting MDR. The observed high levels of antibiotic resistance, combined with the significant genetic diversity of these strains, suggest a potential public health risk.

Investigation of Antibiotic Resistance of E. coli Associated with Farm Animal Feces with Participation of Citizen Scientists.

This paper presents the findings of a large-scale study on antibiotic resistance in bacteria found in farm animal feces across Russia. The study included 6578 samples of farm animal manure from 13 regions in Russia, with the help of citizen scientists. Molecular and microbiological methods were used to analyze 1111 samples of E. coli. The microbiological analysis focused on culturing the microorganisms present in the fecal samples on selective media for E. coli and evaluating the sensitivity of the bacteria to different antibiotics, including ampicillin, tetracycline, chloramphenicol, cefotaxime, and ciprofloxacin. The molecular analysis involved isolating the genomic DNA of the bacteria and conducting PCR assays to detect the vanA, vanB, and mcr-1 antibiotic resistance genes. The results demonstrated significant differences in antibiotic sensitivity of the samples that are morphologically identical to E. coli from different regions. For example, 98.0% and 82.5% of E. coli and other fecal bacterial isolates from the Omsk and Vologda regions lacked antibiotic resistance genes, while 97.7% of samples from the Voronezh region possessed three resistance genes simultaneously. The phenotypic antibiotic sensitivity test also revealed regional differences. For instance, 98.1% of fecal bacterial samples from cattle in the Udmurt Republic were sensitive to all five antibiotics tested, whereas 92.8% of samples from the Voronezh region showed resistance to all five antibiotics. The high level of antibiotic resistance observed may be attributed to their use in farming practices. The distinctive feature of our research is that comprehensive geographical coverage was achieved by using a citizen science platform. Citizen scientists, specifically students from colleges and universities, were responsible for the collection and initial analysis of samples. The project attracted 3096 student participants, enabling the collection and analysis of a significant number of samples from various locations in Russia.

Investigating the changing taxonomy and antimicrobial resistance of bacteria isolated from door handles in a new infectious disease ward pre- and post-patient admittance.

Healthcare-associated infections (HAIs) are a significant burden to health systems, conferring increased morbidity, mortality, and financial costs to hospital admission. Antimicrobial resistance (AMR) further compounds the issue as viable treatment options are constrained. Previous studies have shown that environmental cleaning interventions reduced HAIs. To ensure the effectiveness of these, it is important to analyze the hospital environment at a microbial level, particularly high-touch surfaces which see frequent human interaction. In addition to identifying infectious microorganisms, it is also beneficial to assess typically non-infectious organisms, as traits including AMR can be transferred between the two. Our study identified that there were high levels of antibiotic resistance in typically non-infectious organisms found on high touch surfaces on a hospital ward. However, the organisms identified suggested that the cleaning protocols in place were sufficient, with their presence being due to repeated recolonization events through human interaction after cleaning had taken place.

Profiling the bacterial microbiome diversity and assessing the potential to detect antimicrobial resistance bacteria in wastewater in Kimberley, South Africa

Wastewater treatment plants (WWTPs) are hotspots for pathogens, and can facilitate horizontal gene transfer, potentially releasing harmful genetic material and antimicrobial resistance genes into the environment. Little information exists on the composition and behavior of microbes in WWTPs, especially in developing countries. This study used environmental DNA (eDNA) techniques to examine the microbiome load of wastewater from WWTPs. The DNA was isolated from wastewater samples collected from the treatment trains of three WWTPs in Kimberley, South Africa, and the microbial diversity and composition was compared through 16 S rRNA gene sequencing. The microbes detected were of the Kingdom Bacteria, and of these, 48.27% were successfully identified to genus level. The majority of reads from the combined bacterial data fall within the class Gammaproteobacteria, which is known to adversely impact ecological and human health. Arcobacteraceae constituted 19% of the bacterial reads, which is expected as this family is widespread in aquatic environments. Interestingly, the most abundant bacterial group was Bacteroides, which contain a variety of antibiotic-resistant members. Overall, various antibiotic-resistant taxa were detected in the wastewater, indicating a concerning level of antibiotic resistance within the bacterial community. Therefore, eDNA analysis can be a valuable tool in monitoring and assessing the bacterial microbiome in wastewater, thus providing important information for the optimization and improvement of wastewater treatment systems and mitigate public health risks.

Characterization of two Friunavirus phages and their inhibitory effects on biofilms of extremely drug resistant Acinetobacter baumannii in Dakar, Senegal

BackgroundAcinetobacter baumannii is a gram-negative, opportunistic pathogen, that is responsible for a wide variety of infections and is a significant cause of hospital-acquired infections. A. baumannii is listed by the World Health Organization (WHO) as a critical priority pathogen because of its high level of antibiotic resistance and the urgent need for alternative treatment solutions. To address this challenge, bacteriophages have been used to combat bacterial infections for more than a century, and phage research has regained interest in recent years due to antimicrobial resistance (AMR). However, although the vast majority of deaths from the AMR crisis will occur in developing countries in Africa and Asia, few phages’ studies have been conducted in these regions. In this study, we present a comprehensive characterization of the bacteriophages vAbBal23 and vAbAbd25, actives against extremely drug-resistant (XDR) A. baumannii.MethodsPhages were isolated from environmental wastewaters in Dakar, Senegal. The host-range, thermal and pH stabilities, infection kinetics, one step growth assay, antibiofilm activity assay, sequencing, and genomic analysis, were performed to characterize the isolated phages.ResultsComparative genomic and phylogenetic analyses revealed that vAbBal23 and vAbAbd25 belong to the Caudoviricetes class, Autographiviridae family and Friunavirus genus. Both phages demonstrated activity against strains with capsular type KL230. They were stable over a wide pH range (pH 3 to 9) and at temperatures ranging from 25 °C to 40 °C. Additionally, the phages exhibited notable activity against both planktonic and biofilm cells of targeted extremely drug resistant A. baumannii. The results presented here indicate the lytic nature of vAbBal23 and vAbAbd25. This is further supported by the absence of genes encoding toxins, resistance genes and bacterial virulence factors, highlighting their potential for future phage applications.ConclusionPhages vAbBal23 and vAbAbd25 are promising biological agents that can infect A. baumannii, making them suitable candidates for use in phage therapies.

Longitudinal genomic surveillance of a UK intensive care unit shows a lack of patient colonisation by multi-drug-resistant Gram-negative bacterial pathogens.

Vulnerable patients in an intensive care unit (ICU) setting are at high risk of infection from bacteria including gut-colonising Escherichia coli and Klebsiella species. Complex ICU procedures often depend on successful antimicrobial treatment, underscoring the importance of understanding the extent of patient colonisation by multi-drug-resistant organisms (MDROs) in large UK ICUs. Previous work on ICUs globally uncovered high rates of colonisation by transmission of MDROs, but the situation in UK ICUs is less understood. Here, we investigated the diversity and antibiotic resistance gene (ARG) carriage of bacteria present in one of the largest UK ICUs at the Queen Elizabeth Hospital Birmingham (QEHB), focusing primarily on E. coli as both a widespread commensal and a globally disseminated multi-drug-resistant pathogen. Samples were taken during highly restrictive coronavirus disease 2019 (COVID-19) control measures from May to December 2021. Whole-genome and metagenomic sequencing were used to detect and report strain-level colonisation of patients, focusing on E. coli sequence types (STs), their colonisation dynamics and antimicrobial resistance gene carriage. We found a lack of multi-drug resistance (MDR) in the QEHB. Only one carbapenemase-producing organism was isolated, a Citrobacter carrying bla KPC-2. There was no evidence supporting the spread of this strain, and there was little evidence overall of nosocomial acquisition or circulation of colonising E. coli. Whilst 22 different E. coli STs were identified, only 1 strain of the pandemic ST131 lineage was isolated. This ST131 strain was non-MDR and was found to be a clade A strain, associated with low levels of antibiotic resistance. Overall, the QEHB ICU had very low levels of pandemic or MDR strains, a result that may be influenced in part by the strict COVID-19 control measures in place at the time. Employing some of these infection prevention and control measures where reasonable in all ICUs might therefore assist in maintaining low levels of nosocomial MDR.

'Some patients demand for a prescription of an antibiotic': an assessment of barriers and facilitators to rational antimicrobial use in a private health facility in Uganda.

Antimicrobial misuse and overuse propagate antimicrobial resistance, yet data on factors influencing antibiotic prescription decisions in low-resource settings are limited. We describe factors influencing antimicrobial prescription at a large tertiary care private not-for-profit hospital in Uganda. We conducted a descriptive phenomenology qualitative study involving face-to-face in-depth interviews of 12 purposively selected prescribers (four intern doctors, six medical officers and two Internal Medicine physicians) in a private not-for-profit hospital in Kampala, Uganda. Audio recordings and filed notes were transcribed verbatim and analysed manually by content analysis. Emerging themes and sub-themes were recorded and reported. Three broad themes emerged: experience with antimicrobial use in Uganda, barriers and facilitators to rational antimicrobial prescription and measures to address irrational antimicrobial use. Participants recognized that antibiotics are often used irrationally, prescribed even when there is uncertainty regarding clinical evidence for infection, and influenced by drug promoters, and noted high levels of antibiotic resistance. Patients' symptoms and clinical signs, previous experience using antibiotics, fear of bad outcomes, patient demand and expectations, influence from senior colleagues, the turnaround time of clinical investigations and drug marketers were the barriers and facilitators to antimicrobial prescription. Prescribers also acknowledged the need to update clinical guidelines, set up hospital antibiograms, and provide continuous medical education on rational antimicrobial use. A complex interplay of intrinsic and extrinsic factors influences antibiotic prescribing decisions in this hospital. Targeted interventions through continuous education and training for prescribers, providing local prescription guidelines and antibiograms and implementing regulations on over-the-counter antibiotic sales are needed to implement robust antimicrobial stewardship programmes to curb antimicrobial resistance successfully.

Characterization of Antibiotic Resistance Profiles in the Oral Microbiota of the Pakistani Population.

Background The oral microbiota's resistance to antibiotics presents a serious threat to world health, especially in developing nations where misuse of antibiotics is common. Objective The objective of this study was to characterize the antibiotic resistance profiles in the oral microbiota of Pakistani adults. Methodology The Department of Microbiology at Akhtar Saeed Medical and Dental College in Lahore,Pakistan, carried out a cross-sectional study from January 2022 to December 2022. Oral swabs were collected from 240 adults (aged 18 and older) who had not used antibiotics in the past three months. The disk diffusion method was used for both antibiotic susceptibility testing and bacterial cultures. Descriptive statistics and logistic regression analysis were conducted using IBM SPSS Statistics for Windows, Version 25 (Released 2017; IBM Corp., Armonk, New York, United States) to examine associations within the demographic data. Results The study examined 240 participants, comprising 133 students (55.42%), 64 professionals (26.67%), and 43 individuals in other occupations (17.92%). Of the participants, 128 were male (53.33%) and 112 were female (46.67%).With 81 isolates (33.75%), Streptococcus mutans was the most common species of bacterium, followed by Staphylococcus aureus with 69 isolates (28.75%). The majority of cases (n = 72; 30.00%) were resistant to penicillin, followed by erythromycin (22.50%) in 54 instances and tetracycline (19.58%) in 47 cases. Age group (50 years and above; β = 0.120, OR = 1.128, p = 0.017), penicillin resistance (β = 0.150, OR = 1.162, p = 0.001), erythromycin resistance (β = 0.120, OR = 1.128, p = 0.013), and ciprofloxacin resistance (β = 0.130, OR = 1.139, p = 0.014) were all significantly associated with the results of the regression analysis. Additionally, resistance was positively associated with the occupation "student" (β = 0.110, OR = 1.116, p = 0.047). Conclusion The high levels of antibiotic resistance observed, particularly in older age groups and certain occupations, underscore the urgent need for enhanced antibiotic stewardship and regulatory measures in Pakistan.

Epidemiology of Bacteremia in Patients with Hematological Malignancies and Hematopoietic Stem Cell Transplantation and the Impact of Antibiotic Resistance on Mortality: Data from a Multicenter Study in Argentina.

The epidemiology of bacteremia and the antibiotic resistance profile (ARP) of Gram-negative bacilli (GNB) in hematological malignancies (HM) and hematopoietic stem cell transplant (HSCT) patients may differ according to geographic region. In addition, multidrug-resistant organisms (MDROs) may impact mortality. This is a prospective, observational, and multicenter study. The first episodes of bacteremia in adult patients with HM or HSCT were included. The risk factors for 30-day mortality were identified. One thousand two hundred and seventy-seven episodes were included (HM: 920; HSCT: 357). GNB were isolated in 60.3% of episodes, with Enterobacterales (46.9%) and P. aeruginosa (8.5%) being the most frequent. Gram-positive cocci were isolated in 41.9% of episodes, with coagulase-negative staphylococci (19.8%) and S. aureus (10.4%) being the most frequent. MDROs were isolated in 40.2% (24.4% GNB). The ARP of GNB in patients with HM vs. HSCT was cefepime: 36.8% vs. 45.7% (p = 0.026); piperacillin-tazobactam: 31.05% vs. 45.2% (p < 0.0001); carbapenems: 18.9% vs. 27.3% (p = 0.012); and aminoglycosides: 9.3% vs. 15.4% (p = 0.017), respectively. Overall mortality between patients with HM and HSCT was 17.5% vs. 17.6% (p = 0.951), respectively. The risk factors for mortality were relapsed and refractory underlying disease, corticosteroids use, respiratory source, septic shock, and GNB resistant to meropenem, while 7-day clinical response was a protective factor for survival. Bacteremia was frequently caused by GNB, with a large proportion of MDROs and a high level of antibiotic resistance, especially in patients with HSCT. Carbapenem-resistant GNB bacteremia was associated with a significant increase in mortality.

Multiple mechanisms enable broad-spectrum activity of the Pelargonium sidoides root extract EPs 7630 against acute respiratory tract infections.

There is clinical evidence showing that the Pelargonium sidoides root extract EPs 7630 is a safe and effective treatment for a range of acute infectious respiratory illnesses. Moreover, EPs 7630 has been shown to reduce the use of antibiotics, which is important in the context of rising antibiotic resistance levels. A wide range of mechanisms appears to contribute to the beneficial effects of EPs 7630, e.g. antibacterial, antiviral, immunomodulatory, and epithelial barrier effects. This broad spectrum of pharmacological activities seems to enable the clinical activity of EPs 7630 against multiple respiratory infections. In particular, the combination of antiviral and immunomodulatory effects may enable EPs 7630 to tackle acute viral respiratory infections both in early stages of the disease process, which are driven by virus replication, as well as in later stages, which are caused by an overshooting immune response. Hence, EPs 7630 is a prime example of a plant extract with evidence-based clinical efficacy, including a solid understanding of the underlying mechanisms of action. The example of EPs 7630 demonstrates that plant extracts have a potential role as evidence-based clinical treatments and that they deserve pre-clinical and clinical testing and investigation in the same way as any other drug class.

Etiology of nosocomial infections and antibiotic resistance (level of antibiotic resistance) of identified pathogens in patients with traumatic chest injuries

Background. Chest injuries and wounds are common during armed conflicts, with frequent nosocomial infections and mortality up to 35-45% [1-4]. Infectious complications associated with multidrug-resistant microorganisms are an urgent issue in the management of patients with trauma. Aim. To conduct a retrospective review of the main causative agents of infectious complications in patients with traumatic chest injuries and evaluate antibiotic resistance of isolated pathogens. Materials and methods. Samples for microbiological examination were obtained from 160 patients with chest trauma and nosocomial complications. The samples included sputum, pleural fluid, bronchial washings obtained by fiberoptic bronchoscopy, and tracheal secretions. Antibacterial susceptibility tests were performed, and the antibiotic resistance mechanisms in isolated microorganisms were determined. Results. Gram-negative pathogens accounted for 93% of cases. The following organisms prevailed: Klebsiella pneumoniae – 42%, Acinetobacter baumannii – 28%, Pseudomonas aeruginosa – 18%, Escherichia coli – 9%. Of note, 91.4% of K. pneumoniae strains produced extended-spectrum β-lactamases and carbapenemases. The percentage of multidrug-resistant and pandrug-resistant strains was 48.2% and 52%, respectively. Conclusion. The data obtained indicate a wide spread of gram-negative microorganisms and their multiple resistance in patients with traumatic breast injuries complicated by nosocomial infection.

Multidrug-resistant bacteria in healthcare-associated infections among pediatric patients in Lima, Peru: a call for antibiotic stewardship programs

Abstract Background Healthcare-associated infections (HAIs) in children contribute to elevated morbidity and mortality rates. While the surveillance of antibiotic-resistant bacteria involved in HAIs is important, there is limited data available in Latin America. The present study aimed to evaluate the antibiotic resistance levels in bacteria isolated from hospitalized patients with HAIs in a pediatric referral center in Lima – Peru. Methods Surveillance data of HAIs from November 2021 to June 2023 among pediatric patients at Instituto Nacional de Salud del Niño San Borja was prospectively collected and reviewed. The dataset included comprehensive information on the clinical and epidemiological characteristics of patients, bacteria isolation sites and identification, as well as resistance profiles to 13 antibiotics. HAIs included were central line-associated bloodstream infections (CLABSI), catheter-associated urinary tract infections (CAUTI) and ventilator-associated pneumonia (VAP). Results We included 143 bacterial isolates from pediatric patients hospitalized with HAIs, of which 53.85% were male (n=77). The median age of the patients was 7 months (IQR: 2 -36). A total of 44.76% (n=64) had congenital diseases and 20.28% (n=29) had cancer. Most of the isolates were collected from pediatric Intensive Care Unit (n=104, 72.73%). The median time from the hospital admission to the appearance of HAIs was 17 days (IQR: 7-28). The most frequent isolates were Gram negative bacteria: Klebsiella pneumoniae (n=33), Pseudomonas aeruginosa (n=34) and Escherichia coli (n=24). Among Gram positive bacteria, Staphylococcus epidermidis (n=5) and Staphylococcus aureus (n=5) were the most frequent species. Regarding the site of isolation, the primary etiological agent in CLABSI was K. pneumoniae (n=18); in CAUTI, E. coli (n=13) and in VAP P. aeruginosa (n=9). Multidrug-resistant (MDR) isolates were identified, mainly among K. pneumoniae (62.50%), E. coli (54.55%), and P. aeruginosa (26.74%). Difficult-to-treat resistance was only present in 2.94% of P. aeruginosa isolates. Overall resistance to piperacillin-tazobactam was below 16%. Resistance to cephalosporins was higher than 40% for K. pneumoniae and E. coli isolates, with frequencies exceeding 60% for cefuroxime, ceftazidime, ceftriaxone, cefepime and cefoperazone/sulbactam. E. coli and K. pneumoniae resistance to carbapenems was below than 10%; however, P. aeruginosa resistant isolates were identified in 38.24% and 39.39% for meropenem and imipenem, respectively. Ciprofloxacin resistance was frequent among E. coli (70%) and K. pneumoniae (60.87%), whereas only 26.67% of P. aeruginosa. Amikacin resistance was detected in K. pneumoniae and P. aeruginosa only, with a frequency of 23.08% and 20%, respectively. Conclusion Alarming levels of antibiotic-resistant bacteria were found in HAIs among pediatric patients. Our results highlight the need of supporting initiatives for HAIs control, developing institutional guidelines for prevention and strengthening antibiotic stewardship in pediatric patients. Table 1: Antibiotic resistance profiles of the main microorganisms of healthcare-associated infections (November 2021 – June 2023)

An investigative study on Yersinia enterocolitica in animals, humans and dried milk in New Valley Governorate, Egypt

BackgroundYersiniosis is one of the most significant intestinal disorders caused by Yersinia enterocolitica and affects both humans and animals. This study aimed to investigate the prevalence of Y. enterocolitica in New Valley Governorate, Egypt in animals, humans, fresh milk and dried milk. Additionally, this study analyzed the presence of virulence genes, including ail and Yst in tested isolates and conducted a phylogenetic analysis to determine the genetic similarity between human, and animal Y. enterocolitica isolates. Finally, the antimicrobial resistance patterns of the isolates were examined.ResultsAmong the 982 samples examined, the prevalence of Y. enterocolitica based on ISO10273-2017 was 11.7% in animal samples including 12.8% of animal faeces, and 10.4% in milk samples. Moreover, the prevalence of Y. enterocolitica was 13.2% in human stool, and 9.5% in dried milk samples. The molecular characterization of the six randomly selected isolates showed that the 16S rRNA, ail and Yst genes were found in 50, 33.3 and 100% of the examined Y. enterocolitica isolates, respectively. Phylogenetic analysis of animal and human isolates based on the 16S rRNA gene revealed a high degree of similarity between the isolates. All the tested animal and human Y. enterocolitica isolates (100%) were resistant to ampicillin and cefotaxime, but highly sensitive to norfloxacin.ConclusionsThe high prevalence of Y. enterocolitica in animal and human samples with high degrees of genetic similarity poses a threat to public and animal health. Animal faeces, milk and milk powder represent the main sources of Y. enterocolitica infection in humans. Additionally, high levels of antibiotic resistance of Y. enterocolitica can cause public health hazards by leading to the failure of disease prevention and treatment programs in humans and animals.

Assessment of prevalence, antibiotic resistance, and virulence profiles of biofilm-forming Enterococcus faecalis isolated from raw seafood in Bangladesh

Enterococcus faecalis are often resistant to different classes of antibiotics, harbor virulence determinants, and produce biofilm. The presence of E. faecalis in raw seafood exhibits serious public health significance. This study aimed to identify antibiotic resistance patterns and virulence factors in biofilm-forming E. faecalis strains extracted from seafood in Bangladesh. A total of 150 samples of raw seafood, comprising 50 shrimps, 25 crabs, and 75 fish, were collected and subjected to culturing, biochemical, and PCR assays to detect E. faecalis. The biofilm-forming abilities of the isolates were determined by Congo Red agar (CRA) plate and Crystal Violet Micro-titer Plate (CVMP) tests. Antibiotic resistance profiles were evaluated using the disk diffusion method. Virulence genes of the isolates were detected by PCR assay. The occurrence of E. faecalis was 29.3 % (44/150), which was higher in crabs and fish (36 %) than in shrimps (16 %). In CRA and CVMP tests, biofilm-forming abilities were observed in 88.64 % of the isolates, whereas 11 (25 %) and 28 (63.6 %) were strong- and intermediate-biofilm formers, respectively. All the isolates contained at least two virulence genes, including pil and ace (97.7 %), sprE (95.5 %), gelE (90.9 %), fsrB (79.6 %), agg (70.5 %), fsrA (68.2 %), and fsrC (61.4 %). All the isolates were phenotypically resistant to penicillin, followed by ampicillin and rifampicin (86.4 %), erythromycin (13.7 %), and tetracycline, vancomycin, norfloxacin, and linezolid (2.3 %). Resistant gene blaTEM was found in 61.4 % of the isolates. Moreover, the study found that E. faecalis strains with strong biofilm-forming capabilities had significantly higher levels of virulence genes and antibiotic resistance (p < 0.05) compared to those with intermediate and/or no biofilm-forming abilities. To the best of our knowledge, this research represents the first instance in Bangladesh of assessing antibiotic resistance and identifying virulence genes in biofilm-forming E. faecalis strains isolated from seafood samples. Our study revealed that seafood is a carrier of antibiotic-resistant, virulent, and biofilm-forming E. faecalis, demonstrating a potential public health threat.

Public health implications of antibiotic resistance in sewage water: an epidemiological perspective

The emergence and rapid spread of antibiotic resistance pose a major threat to global health, attributing to misuse and overuse of antibiotics resulting in antibiotics-resistant bacteria through natural mutation or transfer of resistance genes. A cross-sectional study was carried out, in which a total of 36 samples were systematically collected; of these, 26 were derived from the wastewater efflux and 10 from the receiving waters at several critical junctures along the Sutlej River. Herein, this study elucidated elevated levels of antibiotic resistance among bacterial isolates sourced from urban wastewater. Escherichia coli (E. coli) was the highest at 90% among the isolates, followed by Klebsiella pneumoniae (K. pneumoniae) at 58%, Pseudomonas aeruginosa (P. aeruginosa) at 55%, and Salmonella spp. at 53%. Many antibiotics were found to be more resistant including Ciproflaxacin, Co-Trimaxazole, Ampicillin and Tetracycline. Several antibiotic-resistance genes were found in isolated bacterial spp., such as Aminoglycosides (aadA), Sulfonamides (Sul1, Sul3), Tetracyclines (Tet (A/B/D)) and Cephalosporins (Bla_CTM X) at 41%, 35%, 29% and 12% respectively. Furthermore, the development of innovative wastewater treatment models and surveillance programs are crucial to counteract the dissemination of antibiotic resistance. To investigate the genetic determinants of antibiotic resistance, molecular analysis was performed, including DNA isolation, PCR amplification, and sequence analysis. The study helps investigate a diverse range of ARBs and ARGs in wastewater, which highlights the need of better laws for antibiotic usage and wastewater treatment processes. This investigation also stresses on regular monitoring of ARBs and ARGs in sewage wastewater. Through proactive interventions and sustained scientific inquiry, we can strive toward preserving environmental integrity and public health for successive generations.Graphical

Surface hydrophilicity promotes bacterial twitching motility.

The bacterial type IV pilus (T4P) is a critical virulence factor for many medically important pathogens, some of which are prioritized by the World Health Organization for their high levels of antibiotic resistance. The T4P is known to propel bacterial twitching motility, the analysis of which provides a convenient assay for T4P functionality. Here, we show that bile salts and other detergents augment the twitching of multiple bacterial pathogens. We identified the underlying mechanism as the alteration of surface hydrophilicity by detergents. Consequently, hydrophilic surfaces like those of glass or plasma-treated polystyrene promote bacterial twitching, bypassing the requirement for detergents. The implication is that surface properties, such as those of tissues and medical implants, significantly impact the functionality of bacterial T4P as a virulence determinant. This offers valuable insights for developing countermeasures against the colonization and infection by bacterial pathogens of critical importance to human health on a global scale.

Photocatalysis Inhibits the Emergence of Multidrug-Resistant Bacteria in an Antibiotic-Resistant Bacterial Community in Aquatic Environments.

Bacterial antibiotic resistance has recently attracted increasing amounts of attention. Here, an artificially antibiotic-resistant bacterial community (ARBC) combined with five different constructed antibiotic-resistant bacteria (ARB) with single antibiotic resistance, namely, kanamycin (KAN), tetracycline (TET), cefotaxime (CTX), polymyxin B (PB), or gentamicin (GEM), was studied for the stress response to photocatalysis. With photocatalytic inactivation, the transfer and diffusion of antibiotic resistance genes (ARGs) in the ARBC decreased, and fewer multidrug-resistant bacteria (MDRB) emerged in aquatic environments. After several days of photocatalytic inactivation or Luria broth cultivation, >90% ARB were transformed to antibiotic-susceptible bacteria by discarding ARGs. Bacteria with double antibiotic resistance were the dominant species (99%) of residual ARB. The changes in ARG abundance varied, decreasing for the GEM and TET resistance genes and increasing for the KAN resistance genes. The change in the antibiotic resistance level was consistent with the change in ARG abundance. Correspondingly, point mutations occurred for the KAN, CTX and PB resistance genes after photocatalytic inactivation, which might be the reason why these genes persisted longer in the studied ARBC. In summary, photocatalytic inactivation could reduce the abundance of some ARGs and inhibit the emergence of MDRB as well as block ARG transfer in the bacterial community in aquatic environments. This work highlights the advantages of long-term photocatalytic inactivation for controlling antibiotic resistance and facilitates a better understanding of bacterial communities in real aquatic environments.