Epidemiology and outcomes of vancomycin-resistant enterococcus infections: a systematic review and meta-analysis.

Vancomycin-resistant enterococci (VRE) cause many infections in the healthcare context. Knowledge regarding the epidemiology and burden of VRE infections, however, remains fragmented. We aimed to summarize recent studies on VRE epidemiology and outcomes in hospitals, long-term-care facilities (LTCFs) and nursing homes worldwide based on current epidemiological reports. We searched MEDLINE/PubMed, the Cochrane Library, and Web of Science for observational studies, which reported on VRE faecium and faecalis infections in in-patients published between January 2014 and December 2020. Outcomes were incidence, infection rate, mortality, length of stay (LOS), and healthcare costs. We conducted a meta-analysis on mortality (PROSPERO registration number: CRD42020146389). Of 681 identified publications, 57 studies were included in the analysis. Overall quality of evidence was moderate to low. VRE incidence was rarely and heterogeneously reported. VRE infection rate differed highly (1-55%). The meta-analysis showed a higher mortality for VRE faecium bloodstream infections (BSIs) compared with VSE faecium BSIs (risk ratio, RR 1.46; 95% confidence interval (CI) 1.17-1.82). No difference was observed when comparing VRE faecium vs VRE faecalis BSI (RR 1.00, 95% CI 0.52-1.93). LOS was higher in BSIs caused by E. faecium vs E. faecalis. Only three studies reported healthcare costs. In contrast to previous findings, our meta-analysis of included studies indicates that vancomycin resistance independent of VRE species may be associated with a higher mortality. We identified a lack of standardization in reporting outcomes, information regarding healthcare costs, and state-of-the-art microbiological species identification methodology, which may inform the set-up and reporting of future studies.

Impact of discontinuing contact precautions and enforcement of basic hygiene measures on nosocomial vancomycin-resistant Enterococcus faecium transmission.

OBJECTIVES: Vancomycin-resistant Enterococcus faecium (VREfm) has emerged as a pathogen of major concern for public health. Although definitive evidence is lacking, contact precautions have been a crucial element in infection prevention and control (IPC) strategies designed to limit nosocomial VRE transmission. This study investigated the effect of discontinuing contact precautions while enforcing basic hygiene measures, including hand hygiene, environmental cleaning and antiseptic body washing, for patients with VRE in intensive care units (ICUs) on the prevention of nosocomial VRE transmission causing bacteraemia. METHODS: Contact precautions were discontinued in January 2018. In total, 96 VREfm isolates from 61 patients with VREfm bacteraemia and/or colonization hospitalized in eight ICUs in a tertiary care hospital in 2016 and 2019 in were characterized by whole-genome sequencing. VRE transmission was investigated using patient movement data and admission screening for reliable identification of nosocomial acquisition. RESULTS: Discontinuation of contact precautions did not increase VREfm transmission events (eight in 2016 vs one in 2019). While the rate of endogenous VREfm was similar in both years (38% vs 31%), the number of non-colonized patients prior to VREfm bacteraemia was 16 (16/29, 55%) in 2019, which was significantly higher than in 2016 (8/32, 25%). The mean incidence density for VREfm bacteraemia was similar for both years (0.26 vs 0.31 per 1000 patient-days in 2016 and 2019, respectively). CONCLUSION: Discontinuation of contact precautions while enforcing basic hygiene measures did not lead to an increase in nosocomial bloodstream infection rates due to VREfm transmission in a hyperendemic ICU setting.

In Search of Patient Zero: Visual Analytics of Pathogen Transmission Pathways in Hospitals.

Pathogen outbreaks (i.e., outbreaks of bacteria and viruses) in hospitals can cause high mortality rates and increase costs for hospitals significantly. An outbreak is generally noticed when the number of infected patients rises above an endemic level or the usual prevalence of a pathogen in a defined population. Reconstructing transmission pathways back to the source of an outbreak - the patient zero or index patient - requires the analysis of microbiological data and patient contacts. This is often manually completed by infection control experts. We present a novel visual analytics approach to support the analysis of transmission pathways, patient contacts, the progression of the outbreak, and patient timelines during hospitalization. Infection control experts applied our solution to a real outbreak of Klebsiella pneumoniae in a large German hospital. Using our system, our experts were able to scale the analysis of transmission pathways to longer time intervals (i.e., several years of data instead of days) and across a larger number of wards. Also, the system is able to reduce the analysis time from days to hours. In our final study, feedback from twenty-five experts from seven German hospitals provides evidence that our solution brings significant benefits for analyzing outbreaks.