An Economic Evaluation Estimating the Clinical and Economic Burden of Increased Vancomycin-Resistant Enterococcus faecium Infection Incidence in Japan

Unveiling the drivers of vancomycin-resistant enterococcus in China: A comprehensive ecological study

Background

Vancomycin resistant enterococci (VRE) are now considered a global public health issue. In this study, we explored the relationship between vancomycin resistance incidence and various demographic and climatic factors.

Methods

This retrospective study was performed between January 1st, 2014 and December 31st, 2021. Data covering the consumption of vancomycin, the prevalence of vancomycin resistance, and relevant demographics were collected. Spearman's rank correlation, beta regression, and spatial statistical analysis were performed using R version 4.2.2 and ArcGIS version 10.7.

Results

Spearman's rank correlation described the positive relation between vancomycin consumption and the prevalence of vancomycin resistant Enterococcus faecium (VREfm). Multiple regression analysis showed that vancomycin consumption, rural population, proportion of population aged ≥65, annual temperature, and bed number in medical institutions per thousand people were significantly correlated with VREfm prevalence (r = 56.22, p < 0.001; r = 0.0002, p < 0.001; r = 0.06, p < 0.001; r = -0.07, p < 0.001; and r = -0.37, p < 0.001, respectively).

Conclusions

Vancomycin utilization was the predominant factor contributing to VREfm resistance; the effects of rural populations and the proportion of the population aged ≥ 65 were significant but relatively minimal. Annual temperature and the number of beds in medical institutions per thousand people were protective factors against VREfm.

Vancomycin-resistant Enterococcus faecium: A current perspective on resilience, adaptation, and the urgent need for novel strategies

Vancomycin-resistant Enterococcus faecium (VREfm) has become a critical opportunistic pathogen, urgently requiring new antimicrobial strategies due to its rising prevalence and significant impact on patient safety and healthcare costs. VREfm continues to evolve through mutations and the acquisition of new genes via horizontal gene transfer, contributing to resistance against several last-resort antibiotics. Although primarily hospital-associated, VREfm are also detected in the community, food chain, livestock, and environmental sources like wastewater, indicating diverse transmission pathways and the need for a One Health approach. Advances in genomics have shed light on VREfm's persistence in hospital settings, particularly its adaptation to the gastrointestinal tract of hospitalized patients, recent clonal shifts, and the dominance of specific clonal lineages. Despite extensive research, significant gaps remain in understanding the molecular mechanisms behind VREfm's unique adaptation to clinical environments. In this review, we aim to present an overview of VREfm current prevalence, mechanisms of resistance, and unveil the adaptive traits that have facilitated VREfm's rise and global success. A particular focus is given to key plasmids, namely linear plasmids, virulence factors, and bacteriocins as potential drivers in the global emergence of the ST78 clonal lineage. We also address diagnostic challenges and the limited treatment options available for VREfm, as well as emerging antibiotic alternatives aimed at restoring gut microbiota balance and curbing VREfm proliferation. A multifaceted approach combining research, clinical practices, and public health policies is crucial to mitigate the impact of this superbug and preserve antimicrobial effectiveness for future generations.

Cumulative incidence of vancomycin-resistant Enterococcus faecium detection by patient characteristics or possible exposures: prioritization of patients for active screening culture

BACKGROUND

The target population for active surveillance culture (ASC) of vancomycin-resistant Enterococcus species (VRE) by stool or rectal swabs has not been fully determined during VRE outbreaks in healthcare settings in non-VRE endemic situation.

AIM

To evaluate cumulative incidences of VRE detection during a vancomycin-resistant Enterococcus faecium outbreak to determine reasonable target populations for ASC.

METHODS

Cases included inpatients whose first VRE-positive sample was obtained at Shizuoka General Hospital between February 2022 and January 2023, during which we conducted admission screening for possible high-risk patients, bi-weekly screening of all inpatients, admission and discharge screening in the high-care unit, and screening of contacts in each ward using stool or rectal samples. We calculated cumulative incidences of VRE detection for those screened by patient characteristics or possible exposure.

FINDINGS

Among 60 cases identified, 55 (92%) were by ASC. Cumulative incidence was higher for contacts (6.4%, 15/234) than for those identified by other screening methods (0.5%, 40/8565). Among the patients identified through admission screening, those previously hospitalized in areas of reported VRE outbreaks had the highest cumulative incidence (6.6%, 5/78) followed by patients requiring toilet assistance (3.7%, 6/161). A bundle approach including ASC and prompt contact precautions by the hospital infection control team, local public health centre, and local and national infection control experts helped terminate the outbreak in seven months.

CONCLUSION

Patients with contacts, prior hospitalization in areas with known VRE outbreaks, and who need toilet assistance appear to be high-risk populations for VRE detection and are candidates for ASC.

Identification of Antimicrobial-Resistant Zoonotic Bacteria in Swine Production: Implications from the One Health Perspective

Antimicrobial resistance poses a major threat to global health and food security and is primarily driven by antimicrobial use in human and veterinary medicine. Understanding its epidemiology at farm level is crucial for effective control measures. Despite the significant reduction in antibiotic use in conventional livestock production, the swine sector traditionally has a higher level of antibiotic use in veterinary medicine. Consequently, multidrug resistance (MDR) among microbial isolates of swine origin has been relatively frequent. The aim of this study was to assess the presence of multidrug-resistant (MDR) bacteria, enteric pathogens and resistance genes to the main antibiotics used in clinical practice, both within the environment and in animals across pig farms characterized by varying degrees of sanitary status. A total of 274 samples were collected. Of these, 34 samples were collected from the environment (wall swabs, slat swabs and slurry pit), and 240 samples were collected from animals (sows' and piglets' rectal faeces). All samples were analysed for MDR bacteria and enteric pathogens. The study revealed a high frequency of extended-spectrum beta-lactamases (ESBL)-producing Enterobacterales and Campylobacter spp., with ESBL-producing Enterobacterales predominating in high health status farms (environment and animals) and Campylobacter spp. in both high health status and low health status environments. Additionally, a high percentage of methicillin-resistant Staphylococcus aureus (MRSA) was found, mainly in environmental samples from high health status farms, and Clostridioides difficile was distributed ubiquitously among farms and samples. Furthermore, though less frequently, vancomycin-resistant Enterococcus faecium (VRE) was isolated only in high health status farms, and Gram-negative bacilli resistant to carbapenems were isolated only in environmental samples of high health status and low health status farms. This study underscores the importance of surveillance for MDR bacteria in farm animals and their environment, including their waste. Such ecosystems serve as crucial reservoirs of bacteria, requiring national-level surveillance to promote responsible antibiotic use and pandemic control.

Genomic analysis of inter-hospital transmission of vancomycin-resistant Enterococcus faecium sequence type 80 isolated during an outbreak in Hiroshima, Japan

Outbreaks caused by vancomycin-resistant enterococci that transcend jurisdictional boundaries are occurring worldwide. This study focused on a vancomycin-resistant enterococcus outbreak that occurred between 2018 and 2021 across two cities in Hiroshima, Japan. The study involved genetic and phylogenetic analyses using whole-genome sequencing of 103 isolates of vancomycin-resistant enterococci to identify the source and transmission routes of the outbreak. Phylogenetic analysis was performed using core genome multilocus sequence typing and core single-nucleotide polymorphisms; infection routes between hospitals were inferred using BadTrIP. The outbreak was caused by Enterococcus faecium sequence type (ST) 80 carrying the vanA plasmid, which was derived from strain A10290 isolated in India. Of the 103 isolates, 93 were E. faecium ST80 transmitted across hospitals. The circular vanA plasmid of the Hiroshima isolates was similar to the vanA plasmid of strain A10290 and transferred from E. faecium ST80 to other STs of E. faecium and other Enterococcus species by conjugation. The inferred transmission routes across hospitals suggest the existence of a central hospital serving as a hub, propagating vancomycin-resistant enterococci to multiple hospitals. Our study highlights the importance of early intervention at the key central hospital to prevent the spread of the infection to small medical facilities, such as nursing homes, with limited medical resources and a high number of vulnerable individuals.

Epidemiology of vancomycin-resistant enterococci in the United Arab Emirates: a retrospective analysis of 12 years of national AMR surveillance data

INTRODUCTION

Enterococci are usually low pathogenic, but can cause invasive disease under certain circumstances, including urinary tract infections, bacteremia, endocarditis, and meningitis, and are associated with peritonitis and intra-abdominal abscesses. Increasing resistance of enterococci to glycopeptides and fluoroquinolones, and high-level resistance to aminoglycosides is a concern. National antimicrobial resistance (AMR) surveillance data for enterococci from the Middle East and North Africa (MENA) and the Gulf region is scarce.

METHODS

A retrospective 12-year analysis of N = 37,909 non-duplicate diagnostic Enterococcus spp. isolates from the United Arab Emirates (UAE) was conducted. Data was generated by routine patient care during 2010-2021, collected by trained personnel and reported by participating surveillance sites to the UAE National AMR Surveillance program. Data analysis was conducted with WHONET.

RESULTS

Enterococcus faecalis was the most commonly reported species (81.5%), followed by Enterococcus faecium (8.5%), and other enterococci species (4.8%). Phenotypically vancomycin-resistant enterococci (VRE) were found in 1.8% of Enterococcus spp. isolates. Prevalence of VRE (%VRE) was highest for E. faecium (8.1%), followed by E. faecalis (0.9%). A significant level of resistance to glycopeptides (%VRE) for these two species has been observed in the majority of observed years [E. faecalis (0-2.2%), 2010: 0%, 2021: 0.6%] and E. faecium (0-14.2%, 2010: 0%, 2021: 5.8%). Resistance to fluoroquinolones was between 17 and 29% (E. faecalis) and was higher for E. faecium (between 42 and 83%). VRE were associated with higher patient mortality (RR: 2.97), admission to intensive care units (RR: 2.25), and increased length of stay (six excess inpatient days per VRE case), as compared to vancomycin-susceptible Enterococcus spp.

DISCUSSION

Published data on Enterococcus infections, in particular VRE-infections, in the UAE and MENA region is scarce. Our data demonstrates that VRE-enterococci are relatively rare in the UAE, however showing an increasing resistance trend for several clinically important antibiotic classes, causing a concern for the treatment of serious infections caused by enterococci. This study also demonstrates that VRE were associated with higher mortality, increased intensive care unit admission rates, and longer hospitalization, thus poorer clinical outcome and higher associated costs in the UAE. We recommend the expansion of current surveillance techniques (e.g., local VRE screening), stricter infection prevention and control strategies, and better stewardship interventions. Further studies on the molecular epidemiology of enterococci are needed.