OBJECTIVES:Climate change and global warming are major threats for human health and impact the burden of infectious diseases. We investigated the effect of heat stress days (max. perceived temperature ≥32°C) on the incidence of Staphylococcus aureus bacteremia (SAB) and Escherichia coli bacteremia (ECB). METHODS:We performed a post-hoc analysis of a prospective multicenter cohort study with inclusion of all reported SAB and ECB episodes at six tertiary care centers in Germany from 01/2017-12/2019. The effect of the number of heat stress days on the incidence of bacteremia episodes was modelled by a negative binomial regression model with and without underlying seasonal trend. RESULTS:In the prospective multicenter cohort, we included 2870 episodes of SAB and 4421 episodes of ECB. For both entities, we found a significant seasonal variation over the year (ECB peak-to-trough ratio: 1.33, 95% CI: 1.23-1.45, p < 0.001); SAB peak-to-trough ratio: 1.19 (95% CI: 1.07-1.32, p < 0.001), especially in the subgroup of community-acquired ECB (1.47, 95%-CI: 1.32-1.64, p < 0.001). In the model with incorporation of an underlying seasonal trend, we discovered no overall significant association with the number of heat stress days for SAB and ECB. However, in the subgroup of patients with hospital-acquired SAB, we found a significant association after two days of heat (IRR 1.45, 95%-CI: 1.17-1.82, p = 0.001), that remained significant also in a sensitivity analysis focusing on summer days only (IRR 1.50, 95%-CI: 1.18-1.91, p = 0.001). However, after inclusion of an underlying seasonal trend, the incidence of bacteremia cases remained significantly associated with heat stress days only in the subgroup of patients with hospital-acquired SAB. CONCLUSION:Apart from seasonal trends, heat days did not seem to influence the incidence of SAB and ECB overall. The observed association of SAB with heat days in the subgroup of hospital-acquired SAB needs confirmation in further studies.

BACKGROUND:Clostridioides difficile infection (CDI) is a major cause of healthcare-associated diarrhoea with significant morbidity and mortality worldwide. In Germany, CDI incidence has declined in recent years. However, prospective multi-centre data on all-cause in-hospital mortality among CDI patients and on risk factors for death remain scarce. METHODS:We conducted a prospective multi-centre surveillance study in six German university hospitals between 2016 and 2020 to assess all-cause in-hospital mortality among CDI patients. Additionally, multi-variable logistic regression was used to identify risk factors for death. RESULTS:A total of 3592 CDI cases were recorded, of whom 46.7% were female. Overall all-cause in-hospital mortality was 11.7%, whereas CDI-attributable mortality was 0.4% (N = 16). Independent risk factors for death in CDI patients included increasing age (3% per year, adjusted odds ratio [aOR]: 1.03, 95% confidence interval [CI]: 1.02-1.04), longer hospital stay (1% per day, aOR: 1.01, 95% CI: 1.00-1.01), admission to internal medicine (aOR: 1.60, 95% CI: 1.32-1.94) or haematology-oncology (aOR: 2.38, 95% CI: 1.75-3.24) as proxies for patient complexity, and elevated creatinine levels within ± 2 days of sampling (6% per mg/dL, aOR: 1.06, 95% CI: 0.99-1.13). In contrast, diagnosis on a general ward (vs intensive care unit or intermediate care, irrespective of speciality) was associated with a lower risk of death (aOR: 0.34, 95% CI: 0.28-0.42). CONCLUSIONS:Our study provides a comprehensive assessment of all-cause in-hospital mortality among CDI patients in Germany. By identifying robust and easily accessible risk factors for death, our findings support improved risk stratification and may inform targeted management strategies for high-risk patient populations.

Klebsiella pneumoniae sequence type 48 (Kp-ST48) is a globally distributed clone linked to antimicrobial resistance (AMR) yet lacks a comprehensive genomic analysis. Here, we investigated the persistence, transmission dynamics and global context of ST48 in a large tertiary hospital in Berlin, Germany. Between 2014 and 2022, 48 surveillance and 15 putative outbreak Kp-ST48 isolates were isolated in a tertiary care, multi-site hospital in Berlin, Germany. Genomic diversity was analysed by short- and long-read sequencing. Additionally, we included 223 publicly available Kp-ST48 genomes from five continents over 40 years (1982-2022) in the phylodynamic analysis. We identified two genetically distinct clades (A and B) within the global Kp-ST48 population. The global spread of Kp-ST48 was driven by clade B, which included all the genomes from the Berlin hospital. Two hospital-specific lineages (1 and 2) were identified with distinct population dynamics. Lineage 2 was transient and linked to a putative outbreak in 2019. Meanwhile, lineage 1 was first detected in 2014 and persisted for over 8 years until 2022, with multiple putative patient-to-patient and indirect transmission events identified. Carbapenem resistance determinants (ompK35/36 mutations, bla KPC, bla NDM, bla OXA-48, bla VIM) were present in 57% (n=163/286) of genomes, and up to three bla CTX-M-15 copies were found integrated into chromosomes. Although Kp-ST48 generally did not contain a high number of virulence genes, 19 genomes showed potential for AMR-hypervirulence convergence. This study reveals the endemic persistence with outbreak potentials of Kp-ST48 in a hospital over 8 years, characterized by high genome plasticity. Our results highlight the global distribution of this clone, which warrants continuous surveillance.

OBJECTIVES:Infection prevention and control (IPC) and antimicrobial stewardship (AMS) measures are critical to reducing transmission and infection by Clostridioides difficile (CDI) and other enteric pathogens. This study evaluated the impact of enhanced IPC and AMS on CDI and bloodstream infections (BSIs) caused by vancomycin-resistant enterococci (VRE) and third-generation cephalosporin-resistant Enterobacterales (3GCREB). METHODS:The study was conducted in five German university hospitals from January 2016 to July 2019. IPC and AMS interventions were sequentially enhanced in three departments with high-incidence CDI at baseline using a stepped-wedge cluster intervention approach. Main outcome measures were incidence densities of CDI and BSI caused by VRE and 3GCREB. An interrupted time series analysis was performed to assess the intervention effects during a normalized study period. RESULTS:Across 15 departments, >384,000 patient days were included. Incidence density of target infections was low (CDI, 0.77; VRE BSI, 0.07; and 3GCREB BSI, 0.09 per 1000 patient days). Pooled interrupted time series analysis results showed a significant reduction in CDI incidence density following the enhancement of AMS measures (AMS period regression slopes difference, -0.089; F[p] = 5.400 [0.037]). Regarding the incidence density of VRE/3GCREB BSI, no relevant changes could be observed (regression slopes difference, -0.19; F[p] = 0.667 [0.429]). A subgroup analysis focusing on haematological and oncological departments showed that AMS influenced prescription behaviour according to implemented AMS strategies, but not clinical outcomes. DISCUSSION:Combined with IPC enhanced short-term AMS measures led to a significant reduction in the incidence of CDI, whereas the incidence of BSI by VRE and 3GCREB remained unchanged in sites with well-established baseline IPC and AMS programmes and low incidence of hospital-associated infections.

Background Hospital severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreaks are relevant for patients and healthcare systems within and beyond the pandemic. Aim To explore the characteristics of SARS-CoV-2 outbreaks and their infection prevention and control (IPC) measures during the different pandemic waves. Methods A comprehensive structured template for SARS-CoV-2 outbreaks was developed and filled out by six university hospitals. The main outcome variable was outbreak size (OS). Findings A total of 80 outbreaks and 734 infection cases were enrolled between March 2020 and February 2023. In the majority of outbreaks (85%) a contact tracing (CT) team was in place. In 13 (16%) outbreaks the CT team was exclusively responsible for CT, which was negatively linked to OS when adjusting for SARS-CoV-2 waves (estimate (beta) = -1.350; standard error (SE) = 0.274; P < 0.0001). Patients as index had a greater association with OS than healthcare workers (HCWs) (beta = -0.29; SE = 0.098; P = 0.003). Additionally, the mandatory use of face masks by patients in the presence of HCWs was negatively linked to OS (beta = -0.237; SE = 0.08; P = 0.003). The frequency of patient screening during outbreaks varied considerably, whereby higher frequency screenings for SARS-CoV-2 were negatively associated with OS (beta = -0.358; SE = 0.109; P = 0.001). Conclusion Our data provide insights in non-pharmaceutical outbreak prevention and management, revealing that the mandatory use of face masks by patients in the presence of HCWs and a high patient screening frequency in ongoing outbreaks were significantly associated with smaller outbreaks. Further studies are required to allow for generalizability.

Background Multidrug-resistant organisms pose a significant challenge in intensive care units (ICUs). Despite contact precautions (CP) being recommended as an infection prevention measure, little is known about the burden of CP on health care workers (HCWs). Methods An online survey was conducted between May 2021 and August 2022 at baseline (BP) and intervention period (IP) of a multicenter trial discontinuing CP for patients colonized with third-generation cephalosporin resistant gram-negative bacteria in which 38 ICUs participated. Results 147 HCWs from 33 ICUs (BP), 154 HCWs from 38 ICUs (IP) responded to the survey. At BP, most burdensome were: donning personal protective equipment (PPE) in case of emergency (84.0%), need of additional time (73.5%), elevated time management requirements to complete all daily tasks (68.7%), transport to diagnostic areas (65.2%). A significant reduction during IP was shown for: transport to diagnostic areas (p = .010), elevated time management requirements to complete all daily tasks (p = .004), need of additional time (p = .020), donning and doffing PPE (p = .014), increased hand and surface disinfection (p = .035) and anxiety (p = .031). Conclusions Removing CP may be associated with considerable relief in burden for HCWs. However, removing CP must be guided by defined evidence since infection prevention control must be ensured.

BACKGROUND:Antibiotic consumption is considered an important risk factor for Clostridioides difficile infection (CDI). This ecological analysis investigates the influence of outpatient antibiotic prescriptions in statutory health insurance (SHI) on the admission prevalence of CDI in German hospitals participating in voluntary CDI surveillance through the hospital infection surveillance system (Krankenhaus-Infektions-Surveillance-System; KISS). METHODS:The annual CDI admission prevalence of a hospital at the federal state level was associated with the outpatient antibiotic consumption of the corresponding federal state. The quantification of outpatient antibiotic prescriptions was determined as the average DDD per 1000 insured persons per day. The risk factors for CDI on hospital admission included the annual consumption of the eight substance groups aminopenicillin combinations/staphylococcal penicillins, basic penicillins, cephalosporins, quinolones, lincosamides/macrolides, nitrofurantoin/fosfomycin/nitroxoline, sulphonamides/trimethoprim and tetracyclines, the type of care provided by the hospital, and the calendar year, and were examined using multivariable regression analyses (generalized estimating equations models). RESULTS:Between 2011 and 2019, the number of outpatient antibiotic prescriptions decreased from 13.9 to 10.4 DDD per 1000 insured persons per day (-25%), and the CDI admission prevalence decreased from 0.22 to 0.12 per 100 patients (-45%). Basic penicillins and cephalosporins were identified as risk factors for increased CDI admission prevalence, while nitrofurantoin/fosfomycin/nitroxoline and sulphonamides/trimethoprim were associated with decreased CDI admission prevalence. CONCLUSIONS:A decrease in outpatient antibiotic prescriptions with known risk of developing CDI was associated with a decrease in hospital CDI admission prevalence. Our ecological analysis indicates that rational and restrained antibiotic use in the outpatient setting may reduce the incidence of CDI in the population requiring inpatient treatment.

BackgroundTesting for Staphylococcus aureus (SA) colonization in emergency department (ED) patients may guide prevention strategies against hospital acquired infections (HAIs). This study determined the prevalence of SA carriers in a general ED population, characterized the population, and identified predictors for SA colonization.MethodsA prospective monocentric observational cohort study in a tertiary care hospital collected nasopharyngeal swabs in 1000 adult patients. Polymerase chain reaction (PCR) testing for methicillin resistant and methicillin sensitive SA (MRSA/MSSA) was performed. Risk factor questionnaires and routine data from the clinical information system were captured. Descriptive statistics and binary logistic regression models were applied to report prevalence and outcomes and to identify predictors.ResultsThe prevalence for SA was 33.7% (n = 328; 95%-CI: 30.7-36.8): MSSA 30.9% (n = 301; 95%-CI: 28.0-34.0) and MRSA 2.8% (n = 27; 95%-CI: 1.8-4.0). Key predictors of SA colonization included having a catheter (OR 2.0, 95%-CI 1.0-4.0, p = 0.044) and requiring nursing care (OR 1.9, 95%-CI: 1.2-2.9, p = .007), even after adjusting for age and sex.ConclusionTesting strategies for SA detection in ED need to focus on vulnerable populations with an elevated risk for HAIs and associated adverse outcomes. Individuals requiring nursing care could be a key target population for screening efforts.

Abstract Background/introduction Antipseudomonal antibiotics are frequently used in patients admitted to hospitals. Many of these substances are classified as a reserve or watch status by the WHO. Inappropriate risk assessment of invasive detection of P. aeruginosa (PAE) can be a reason for overuse of antipseudomonal antibiotics. Therefore it is important to define relevant and specific risk factors for invasive PAE detection. Objective The objective of this study was to identify risk factors for invasive detection of PAE in patients upon hospital admission. Methods All patients 18 years of age and older with a detection of PAE and/or Enterobacterales in clinical samples taken within 48 h of admission to one of the hospitals of Charité Universitätsmedizin Berlin between 2015 and 2020 were included into this retrospective cohort study. Results Overall, we included a total of 27,710 patients. In 3,764 (13.6%) patients PAE was detected in clinical samples taken within 48 h after admission. The most frequently detected Enterobacterales was E. coli in 14.142 (51%) patients followed by Klebsiella spp. in 4.432 (16%) patients. Multivariable regression analysis identified that prior colonisation with a multi drug resistant PAE or detection of a PAE in clinical samples during a previous hospitalisation increased the risk for invasive detection of PAE (OR 39.41; 95% CI 28.54–54.39) and OR 7.87 (95% CI 6.60–9.38) respectively. Admission to a specialised ward for patients with cystic fibrosis was associated with an increased risk (OR 26.99; 95% CI 20.48–35.54). Presence of chronic pulmonary disease (OR 2.05; 95% CI 1.85–2.26), hemiplegia (OR 2.16; 95% CI 1.90–2.45) and male gender (OR 1.60; 95% CI 1.46–1.75) were associated with a modest increase in risk for presence of PAE. Conclusion Patients with a prior detection of P. aeruginosa or admission to a cystic fibrosis ward had the highest risk for invasive detection of P. aeruginosa. Adherence to specific risk scores based on local risk factors could help to optimize prescription of anti-pseudomonal antibiotics that categorized as reserve and watch.

Bathing strategies with antiseptic agents, such as Chlorhexidine and Octenidine, have been widely adopted to mitigate infection risks in intensive care units (ICU). However, concerns exist regarding their long-term effects on skin microbiome structures and potential unintended consequences, including antibiotic cross-resistance. This longitudinal study characterized the compositional changes of the skin microbiome of ICU patients upon these two antiseptic bathing strategies when compared to standard water and soap bathing. Samples were collected in a three-armed cluster randomized decolonization trial (registration number DRKS00010475). Skin swabs from 5 different sites and three time points were analyzed by culture-based methods, 16S rRNA-gene amplicon sequencing and multiplex Taq-Man assays for detection of antimicrobial resistance genes (ARG). Our results show that Chlorhexidine bathing led to a sustained reduction of the bacterial biomass on different skin sites, as measured by both molecular and culture-based methods. Thereby, the microbial structures remained largely unaltered both in their diversity and their taxonomic composition. However, the loss of microbiome site-specificity observed on the skin of ICU patients remained unchanged independently from the bathing strategy applied and persisted even after discharge. None of the antiseptic bathing strategies led to an increase or accumulation of antibiotic-resistance determinants on any of the skin sites investigated in this study. Thus, this study suggests that daily patient bathing with 2% Chlorhexidine impregnated cloths or 0.08% Octenidine wash mitts does not impact skin microbiome structures and antibiotic resistance gene accumulation in ICU patients when compared to non-antiseptic water and soap bathing routine.

If antibiotics are used appropriately, the development of antimicrobial resistance (AMR) can be curbed. Many medical students feel that they do not receive sufficient training in this respect during their undergraduate medical education. In recent years, digital learning formats are being successfully employed in student teaching. Our aim was to develop and evaluate a massive open online course (MOOC) on appropriate antibiotic therapy and the development of AMR. The intention was to provide the MOOC as an effective learning format in medical schools and to encourage others to develop their own MOOCs on other topics. We developed a MOOC for medical students that consisted of four modules (M1-4) on bacteriology, microbiology diagnostics, pharmacology, antibiotics, AMR, the One Health approach, principles of appropriate antibiotic therapy, and transfer of knowledge to clinical practice. MOOC learners were asked to answer the same 16 knowledge and five self-assessment questions at the beginning and end of the MOOC and to give course feedback in an anonymous online questionnaire. From July 1, 2021 until June 30, 2022 the MOOC was actively attended by 2061 learners. Of them, 473 (23

Objectives: Patients with haemodialysis catheters are susceptible to dialysis-associated infections, particularly bloodstream infections. There have been few systematic attempts to reduce this burden. Our study aimed to investigate the effect of a multimodal prevention strategy on dialysis-associated infection events (DAIE) among haemodialysis outpatients. Methods: A multicentre, stepped wedge, cluster-randomized controlled trial was done from October 2019 to September 2021. Outpatient dialysis facilities entered into the intervention phase in three randomly assigned clusters, at three predefined time points. The multimodal prevention strategy consisted of infection surveillance and hand hygiene (HH) compliance observation with active feedback and teaching aseptic procedures, and a patient flyer. The primary outcome was incidence rates of different DAIE, such as bloodstream infections, intravenous antimicrobial starts, and local access-site infections per 1000 dialysis. As secondary outcome, we analysed the HH compliance change. Results: A total of 43 haemodialysis outpatient facilities with 11 251 patients and 1 413 457 proceeded haemodialysis were included in the DIPS-trial. Incidence rates were 0.71 DAIE per 1000 dialysis (95% CI, 0.65-0.78) in the control and 0.31 (95% CI, 0.27-0.36) in the intervention group. The univariable analysis yielded an incidence rate ratio (IRR) of 0.44 (95% CI, 0.33-0.59) for DAIE. Especially in patients with a central venous catheter, we saw a significant decrease in DAIE in the intervention group (IRR 0.4; 95% CI, 0.28-0.58). The HH observation combined with feedback and intensified training, resulted in an increase of HH compliance from 58-65%. Discussion: A multimodal prevention strategy showed a significant preventive effect on DAIE among haemodialysis outpatients. This reduction also applied to bloodstream infections, especially in patients with a central venous catheter. (c) 2024 The Author(s). Published by Elsevier Ltd on behalf of European Society of Clinical Microbiology and Infectious Diseases. This is an open access article under the CC BY license (http://creativecommons. org/licenses/by/4.0/).

Aim:SARS-CoV-2 hospital clusters are a challenge for healthcare systems. There is an increased risk of infection for both healthcare workers (HCWs) and patients; cluster countermeasures are also a drain on resources for the wards affected. We analysed to which extent characteristics and dynamics of SARS-CoV-2 clusters varied throughout the pandemic at a German university hospital. Methods:Patient and/or HCW clusters from 10/2020 to 04/2022 were included in the study and grouped by virus variant into i.) clusters comprised of the presumably predominant wild-type, Alpha or Delta (WAD) SARS-COV-2 variants, and ii.) clusters comprised predominantly of Omicron subtype cases. The two groups were compared for specific characteristics and dynamics. Results:Forty-two SARS-CoV-2 clusters and 528 cases were analysed. Twenty-one clusters and 297 cases were attributed to the WAD and 21 clusters and 231 cases to the Omicron group. There were no significant differences in median size (8 vs. 8 cases, p=0.94) or median duration (14 vs. 12 days; p=0.48), nor in the percentage of HCWs involved (46.8% vs. 50.2%; p=0.48). Patients in the WAD group were older (median 75 vs. 68 years of age; p≤0.05). The median time from cluster onset to case onset was significantly shorter for the Omicron group (median 6 vs. 11 days; p≤0.05). Conclusions:Omicron clusters exhibited a more rapid dynamic, forcing all parties involved to adapt to the increased workload. Compared to excessive community case counts, constant Omicron cluster-affiliated case counts and stable cluster characteristics suggest an improved compliance with IPC countermeasures.

Background An important component in fostering the responsible use of antibiotics is training of new and future prescribers in this interdisciplinary topic. Because podcasts are playing an increasing role in medical education, we aimed to develop and evaluate a podcast format with practice and guideline-oriented learning content on antibiotic therapy for medical students and young medical professionals.Methods We developed the concept for the podcast with the direct involvement of medical students and medical experts with teaching experience. We used video conferencing when recording the episodes in order to have quick, easy, and nationwide access to the experts involved. We released an episode every 2 to 4 weeks on the popular podcast platforms. The podcast was promoted through mailing lists, social and print media, and at conferences. The evaluation of episodes was based on user data provided by the platforms and an anonymous feedback questionnaire linked to each episode in the podcast notes.Results Between December 2021 and December 2022 19 episodes of InfectEd: der Antibiotika-Podcast were released. The mean duration of an episode was 91 min. By March 9, 2023, a total of 38,829 downloads and streams had been recorded. The majority of users listened to the podcast on a mobile device. The average playing time per episode was 65%. The feedback questionnaire was completed 135 times. 60.7% of respondents were female, 38.5% male. The majority of respondents were in their twenties and thirties (66.7%). 31.1% were medical students, 25.9% were residents, and 25.2% were specialists. Listeners were asked to rate episodes on a scale from 1 to 6, where 1 was "very good" and 6 was "insufficient." Ratings did not differ significantly between female and male respondents or between medical students and others. 118 respondents (87.4%) reported an increase in knowledge. Free-text feedback frequently emphasized clinical and also exam relevance.Conclusion Our podcast format, developed with a user-centered approach, was broadly distributed and has been well accepted by both medical students and physicians alike. It provides a large number of learners with low-threshold access to current, guideline-orientated content and could be a useful supplement to conventional teaching formats.

Carriage of Extended-Spectrum β-Lactamase-Producing Enterobacterales (ESBL-E) has been increasing over the last decades, especially in the community setting. This successful spread of ESBL-E might be partially explained by the fact that some plasmids with ESBL encoding genes specifically well adapted to Enterobacterales species ( 1 Branger C. Ledda A. Billard-Pomares T. Doublet B. Fouteau S. Barbe V. et al. Extended-spectrum beta-lactamase-encoding genes are spreading on a wide range of Escherichia coli plasmids existing prior to the use of third-generation cephalosporins. Microb Genom. 2018; 4 Google Scholar ). Besides antibiotic use, most important risk factors for ESBL-E acquisition were lifestyle-associated such as travelling or other contact to areas with high ESBL-E prevalence.

Background: Healthcare-associated infections (HAIs) are a major problem in intensive care units (ICUs). The hospital water environment is a potential reservoir for Gramnegative bacteria (GNB), and it has been shown that contaminated sinks contribute to the spread of GNB in outbreak and non-outbreak settings. This study aimed to investigate which sink interventions may reduce GNB infection and colonization rates in the ICU.Methods: A database search (MEDLINE via PubMed, EMBASE via Ovid and ClinicalTrials.gov) was undertaken without restrictions on language or date of publication. Studies of any design were included if they described an intervention on the water fixtures in patient rooms, and presented data about HAI or colonization rates in non-outbreak settings. Acquisition (infection and/or colonization) rates of GNB and Pseudomonas aeruginosa were analysed as outcomes. Results: In total, 4404 records were identified. Eleven articles were included in the final analysis. No randomized controlled trials were included in the analysis, and all studies were reported to have moderate to serious risk of bias. Removing sinks and applying filters on taps had a significant impact on GNB acquisition, but there was high heterogeneity among reported outcomes and sample size among the studies.Conclusion: Few studies have investigated the association of sinks in patient rooms with healthcare-associated acquisition of GNB in non-outbreak settings. Heterogeneity in study design made it impossible to generalize the results. Prospective trials are needed to further investigate whether removing sinks from patient rooms can reduce the endemic rate of HAIs in the ICU. 2023 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Purpose Blood cultures (BCs) are key for pathogen detection in septic patients. We investigated the extent to which sampling was performed and what factors were associated with the absence of general or inadequate BC sampling. Methods We conducted a retrospective cohort study of hospitalized patients with sepsis admitted to one of three EDs in 2018. Primary outcome was the extent of general BC collection of at least 1 set. Secondary outcome was the extent of adequate BC sampling, defined as ≥ 2 sets before antibiotic therapy (AT). Multivariable logistic regression analysis was performed to identify factors associated with deficits in both outcomes. Results 1143 patients were analyzed. BCs were collected from 946 patients. Single BCs were taken from 520 patients, ≥ 2 sets from 426 patients. Overall, ≥ 2 BCs were taken from 349 patients before AT. BC sampling before AT occurred significantly more frequently when ≥ 2 BC sets were taken rather than a single one (81.9%, versus 68.4%, p < 0.001) and this also led to the highest pathogen detection rate in our cohort (65.6%). A body temperature of ≥ 38 °C was the a supporting factor for general and adequate BC collection in all three EDs. Retrospective analysis of 533 patients showed that the qSOFA score had no influence on general or adequate BC collection. Conclusion Data on everyday clinical practice in the pre-analytical phase of microbiological diagnostics shows considerable deficits and indicates the need for more implementation of best practice. The variations identified in BC sampling between EDs should be further investigated.

Abstract Background The environment of healthcare institutions plays a major role in the transmission of multidrug resistant organisms (MDRO) and likely in subsequent healthcare-associated infections (HAIs). Probiotic cleaning products are a novel option for environmental cleaning. They represent a sustainable and biodegradable alternative to conventional chemical disinfectants for controlling microbial bioburden, and preventing pathogen transmission in hospital environments. High-quality studies including randomized clinical trials (RCT) triggered a summary with expert recommendations until further studies allow a critical review and meta-analysis of the data. Methods Infection control experts from five European countries summarized available data as of June 2023. Authors presented their published RCTs, reviewed the existing literature on probiotic cleaning, summarized the results and identified knowledge gaps and subsequent research needs. Results Probiotic cleaning was similarly effective for reducing HAI-related pathogens, enveloped viruses such as SARS-CoV-2 and MDRO in environmental samples compared to conventional chemical disinfectants. More importantly, probiotic cleaning was non-inferior to disinfectants in terms of preventing HAI in a large RCT. In addition, probiotic cleaning has also been shown to reduce antimicrobial resistance genes (ARG), costs and antimicrobial consumption in other hospital trials. They are biodegradable, do not require any protection for chemical hazards, and are compliant with occupational health. A paradigm shift, however, requires a very strong evidence to justify for such a change. In the past, this evidence was limited by the heterogeneity of study design, products, protocols, and few studies on clinical outcomes used in the trials. Furthermore, the regulatory, safety, and quality aspects of probiotic cleaning products are not, yet, completely defined and require clearing by authorities. Conclusion To date, probiotic cleaning is a breakthrough technology and a biological alternative for chemical disinfectant when treating hospital environment. It may also have a positive effect on MDRO transmission. However, the different compositions of probiotic products will require standardization, and more robust data should be generated to support these promising results on different compositions. This may trigger a paradigm shift in cleaning of healthcare institutions from chemical to biological control of the hospital environment.

Background Mycobacterium chelonae is a rare cause of infective endocarditis that is difficult to diagnose and treat. After we found M chelonae in a series of patients, we aimed to investigate its role in cardiovascular prosthesis dysfunction and contamination of bioprostheses as a possible cause of infection. Methods In this collaborative microbiological study, we report on nine patients treated in three cardiovascular surgical departments in Germany, who were found to have M chelonae infection after receiving BioIntegral bioprostheses. We performed fluorescence in-situ hybridisation (FISH) combined with broad-range 16S rRNA gene amplification and sequencing (FISHseq) on samples of native cardiovascular tissue and explanted bioprosthetic material, as well as on 12 unused BioIntegral prostheses. We confirmed FISHseq findings with histological examination by staining for acid-fast bacilli, and M chelonae was differentiated from M abscessus by molecular techniques. Findings Between Dec 1, 2020, and Feb 28, 2022, we identified M chelonae in BioIntegral bioprostheses from three initial patients treated in Berlin that were explanted following dysfunction or suspected endocarditis, visualising morphologically intact FISH-positive mycobacteria. Despite negative mycobacterial culture, we also detected M chelonae in all 12 unused BioIntegral prostheses. The competent authorities in the EU prompted an alert, leading to the identification of six additional patients between March 1, 2022, and July 31, 2023. To find other cases of M chelonae endocarditis, we reviewed the FISHseq results of 1237 cardiovascular samples that were analysed between Jan 1, 2015, and Aug 31, 2022, including 295 samples from 228 bioprostheses supplied by other manufacturers. M chelonae was only detected in six of 41 patients who had received BioIntegral products. Interpretation Bioprostheses manufactured by BioIntegral Surgical might be colonised by M chelonae, which can lead to implant dysfunction. These infections are likely to be missed by conventional routine diagnostics and should be considered in patients with BioIntegral implants and suspected infection or dysfunction. Cases should be reported to public health and regulatory authorities. Routine safety testing of bioprostheses during manufacture should be reconsidered. Funding German Federal Ministry of Education and Research.