Surgical site infections (SSIs) place a significant burden on healthcare systems worldwide. Although surveillance is crucial for obtaining accurate data and developing effective prevention strategies, there are still significant gaps due to the frequent reliance on manual and resource-intensive processes. To gain efficient, in-depth insight, we developed an algorithm for semi-Automated Retrospective Surveillance of Surgical Site Infections (sAReS-SSI), which retrospectively identifies SSIs using existing routine hospital data. sAReS-SSI adopts a patient-centric approach to data analysis, using an ICD-10 and OPS catalogue to detect in-house SSIs through temporal linkage to prior in-house surgeries, refining the NWIF algorithm of the German Institute for Quality and Transparency in Healthcare. sAReS-SSI was evaluated against SSIs that were validated through bedside surveillance in three orthopaedic and trauma surgery wards, as published in the HygArzt study. Its performance was also evaluated in comparison with a reconstructed NWIF algorithm, and contextualised using OP-KISS surveillance reports from the German National Reference Center. sAReS-SSI correctly identified 61 of 65 in-house SSIs published in the HygArzt study. Re-analysis of initially false-positive cases revealed 10 additional true in-house SSIs not captured in HygArzt, yielding a sensitivity of 94.7

Background Multidrug-resistant Escherichia coli display a growing infection control concern in hospitals, yet the duration of fecal carriage and risk factors for persistence are incompletely understood. Methods In this retrospective cohort study, 217 patients with a positive rectal screening for MDR E. coli and a readmission with repeated screening were included. Time to clearance was analyzed using Kaplan-Meier methods. Risk factors were determined with regression analysis. Results At rehospitalization, 51.6% of patients remained colonized. Analysis estimated a median colonization duration of 9.26 months; nearly 20% remained colonized for several years. ICD-10 category K (diseases of the digestive system) was associated with higher rate of persistence (OR 2.07, p = 0.02). Conclusions Colonization with MDR E. coli for a median of around 9 months underscores the relevance of control at readmission. The association of gastrointestinal diseases with prolonged carriage suggests that targeted risk-based screening strategies may be appropriate. Approximately half of patients colonized with MDR E. coli remain colonized at first readmission, and the median carriage duration is around 9 months. A minority may carry the organism for several years. Gastrointestinal diseases lead to a higher risk for prolonged colonization.

Osteomyelitis continues to pose significant challenges in clinical management, with no universally accepted treatment guidelines at either national or international level as of 2025. Amoxicillin/clavulanic acid (AMC) is a widely used β-lactam antibiotic known for its safety, tolerability, and broad-spectrum activity against common osteomyelitis pathogens. This work seeks to determine whether oral AMC could serve as a viable and effective option in the management of osteomyelitis based on the current treatment landscape of osteomyelitis. Preferred Reporting Items for Systematic Reviews (PRISMA) were applied during the preparation of the article. For the structured search in PubMed®, The Cochrane Library, and UpToDate®, key research questions were defined and translated into specific search terms. Inclusion and exclusion criteria were defined using the population-intervention-comparison-outcome-study design strategy. All relevant publications available from 1981 to March 2025 were considered. A total of 1,321 publications were identified. After applying in- and exclusion criteria - supported by automation tools − 104 publications were analysed. The number of primary studies specifically investigating AMC for osteomyelitis is limited. However, available data suggest that AMC is effective and demonstrates non-inferiority compared to standard reference antibiotics. Pharmacokinetic data indicate that prolonged and repeated dosing may enhance distribution into deeper compartments, including bone tissue. Reported adverse effects of AMC are generally mild to moderate, in contrast to alternative agents. The analysis of the included publications and theoretical considerations on the treatment of osteomyelitis show that surgical debridement followed by long-term administration of AMC can be an effective option for empirical therapy.

Alongside surgical therapy, the successful treatment of infection-related nonunion depends on the accurate identification of pathogens so as to ensure targeted anti-infective treatment. The available diagnostic methods continue to exhibit low sensitivity. The aim of the study was to determine the most sensitive method for the accurate diagnosis of infection-related nonunion by comparing sonication with other diagnostic procedures. In a prospective comparative study, 100 patients with nonunions (study group, SG) and 100 patients with planned metal removal (control group, CG) were compared. The diagnostic methods employed included standard culture, enrichment in blood culture bottles after tissue homogenization, sonication with and without membrane filtration, and histopathology. Sensitivity, specificity, and predictive values were calculated. In 133 patients (SG n = 73; CG n = 60), at least one sample was tested positive for a bacterium. Infection was diagnosed in 72 patients (SG n = 45; CG n = 27). Coagulase-negative staphylococci and Cutibacterium acnes were the most frequently detected pathogens. Sonication achieved the highest sensitivity (80.6

BACKGROUND:Monitoring hand disinfection (HD) with direct observation is considered the gold standard but is flawed by the Hawthorne effect (HE). In our project in a German university hospital, we quantified the HE and evaluated possible room-specific differences. METHODS:Data were collected on an intensive care unit (ICU), an intermediate care unit, and a normal ward (NW) each categorized into "patient," "utility/waste," and "other" rooms. While dispensers were monitored by sensors of a full-time active electronic monitoring system, the infection prevention and control staff performed step-by-step observations according to the World Health Organization "5 moments." Periods with and without direct observations were compared regarding the number of HDs performed per patient day (HD/PD) using descriptive evaluation and a linear mixed model. RESULTS:The HE was detected in "patient" rooms on the NW and ICU (+ 31.4%, + 27.4% HD/PD; both P < .01) during observation periods. Opposite effects, expressed by significant decreases in HD/PD during observations, occurred in "utility/waste" rooms on the NW (-57.7%), intermediate care unit (-99.4%), and ICU (-32.9%). CONCLUSIONS:In our setting, the HE varied considerably between wards and room types. As HE occurred in patient rooms, the usual HD compliance during patient care may be lower than directly observed.

Background:The German Infection Protection Act and KRINKO recommend nominating one authorized medical specialist in every medical department as an infection prevention link physician (PLP). Detailed evidence on the contribution of PLPs to reducing infection rates is not available in Germany. Aim:The "HygArzt"-study investigated whether, and to what extent, a PLP in orthopaedics/trauma surgery is able to improve hand hygiene adherence (HHA), process steps of dressing change, nosocomial infection (NI) and surgical site infection (SSI) rates by implementing an infection prevention bundle (IPB). Methods:In consideration of a literature review on infection prevention measures in orthopaedics/trauma surgery and existing departmental hygiene standards, supported by the responsible infection control specialist, an IPB was developed by an interdisciplinary team and implemented by a PLP. The effects of IPB on NI, SSI, and HHA were determined in a pre-post study design on three trauma surgery/orthopaedic wards of a university hospital. Findings:In pre-post comparison HHA was significantly increased, and NI rates were reduced significantly. The greatest increase in adherence occurred in the pre-indications "Before touching a patient" (pre: 37.3%; post: 73.0%), "Before clean/aseptic procedure" (pre: 34.2%; post: 75.5%) and "Before surgery" (pre: 9.7%; post: 57.0%). The analysis of NI and SSI rates (NI: p=0.03; SSI: p=0.01; relative risk (RR) of 0.53 in each case) revealed rate reductions. Conclusion:The implementation of an IPB by a PLP led to an optimisation of processes and to a reduction of SSIs and NIs. PLPs seem to have the potential for targeted, group-specific implementation of complex IPBs.

AimHand-disinfection (HD) is the most effective infection-prevention-measure. HD-performance of health care professionals (HCP) is usually evaluated by compliance observations (CO). The Hawthorne effect (HE) (HCP behave differently under observation) is considered to systematically increase HD-compliance-rates during CO. However, little is known about the specifications of the HE in health care settings. We hypothesized that, due to hand-hygiene`s known impact on patient safety and infection-prevention, the HE does not affect HD performance during direct patient care in patient-rooms.MethodWe conducted a prospective observational trial on an 18-bed surgical intensive care unit (ICU), a 12-bed surgical intermediate care unit (IMC) and a 36-bed surgical normal ward (NW) in a university hospital in Germany. Dispensers of hand sanitizers were equipped with an electronic monitoring system (EMS) (GWA Hygiene, Germany), which recorded the number of HDs per patient hour (HD/PH) and time and location of hand-disinfections. Locations were categorized as follows: 1. Patient rooms (PR); 2. Utility- and waste-disposal-rooms (UWR) and 3. Other rooms (hallways, kitchen, toilets etc.) (OR). Additionally trained infection-control-staff performed hand-hygiene CO according to WHO's Five Moments. The HD/PH during CO was compared to the HD/PH during the same time-periods without CO. Additionally the ratio between HD/PD-change during CO and mean-HD/PD of each ward during the study-period was determined in percentages. Descriptive and analytical statistics were calculated using R. P-values ≤ 0.05 were regarded as significant.Results587.128 HD were electronically recorded during the study-period (February 2022 to May 2023) and CO took place on 72 days. We recorded a significant increase of HD/PH during CO on all three wards in PRs (ICU: 21%, p<0.001; IMC: 11%, p=0.029; NW: 49%, p=0.047). Furthermore we detected a significant increase of HD/PH during CO on ICU (10%, p<0.001) and IMC (11%, p=0.033) in ORs. CO did not significantly affect HD/PH in ORs on NW and in UWR on all three wards.ConclusionsIn our setting, the number of hand-disinfections per patient-hour was significantly increased during compliance-observations especially in patient-rooms, where hand-hygiene is most crucial for infection-prevention. This indicates a lower everyday compliance to WHO`s hand-hygiene indications during patient care than determined by compliance-observations.AcknowledgmentsPaul-Hartmann AG financially supported this study.

OBJECTIVES:Because of a steady increase in the detection of daptomycin-resistant (DAP-R) Staphylococcus aureus at three medical centres in Cologne, Germany, molecular surveillance was established from June 2016 to June 2018 to investigate the causes of the emergence and spread of respective isolates. Seventy-five S. aureus isolates, both DAP-R and DAP-susceptible, were collected from 42 patients for further analysis. METHODS:Broth microdilution was used to determine the MICs for DAP and polyhexamethylene biguanide/polyhexanide (PHMB). To investigate the effect of PHMB on the development of DAP resistance, we performed selection experiments with PHMB. All isolates studied were subjected to whole-genome sequencing. Epidemiological, clinical, microbiological and molecular data were analysed comparatively. RESULTS:Acquisition of DAP resistance was mainly observed in patients with acute and chronic wounds (40/42, 96.2%) treated with antiseptic (32/42, 76.2%) rather than systemic antibiotic therapy using DAP or vancomycin (7/42, 16.7%). DAP-R S. aureus had a diverse genetic background; however, within individual patients, isolates were closely related. At least three potential transmission events were detected. Most DAP-R isolates had concomitant elevated MICs for PHMB (50/54, 92.6%), and in vitro selection experiments confirmed that PHMB treatment is capable of generating DAP resistance. DAP resistance could be linked to 12 different polymorphisms in the mprF gene in the majority of clinical isolates (52/54, 96.3%) as well as in all in vitro selected strains. DISCUSSION:DAP resistance in S. aureus can occur independently of prior antibiotic therapy and can be selected by PHMB. Therefore, wound treatment with PHMB may trigger individual resistance development associated with gain-of-function mutations in the mprF gene.

AbstractBackground:The “HygArzt” project investigated the effectiveness of hygiene measures introduced by an infection prevention link physician (PLP).Objective:To investigate whether the introduction of a standardized aseptic dressing change concept (ADCC) by a PLP can increase hand hygiene adherence and adherence to specific process steps during an aseptic dressing change (ADC) in a trauma surgery and orthopedic department.Methods:We defined 4 required hand disinfection indications: (1) before the preparation of ADC equipment, (2) immediately before the ADC, (3) before the clean phase, and (4) after the ADC. A process analysis of the preintervention phase (331 ADCs) was used to develop a standardized ADCC. The ADCC was introduced and iteratively adopted during the intervention phase. The effect was evaluated during the postintervention phase (374 ADCs).Results:Hand hygiene adherence was significantly increased by the introduction of the ADCC for all indications: (1) before the preparation of the ADC equipment (from 34% before to 85% after, P <.001), (2) immediately before an ADC (from 32% before to 85% after; P < .001), (3) before the clean phase (from 42% before to 96% after; P < .001), and (4) after an ADC (from 74% before to 99% after; P < .001). Overall hand hygiene adherence was analyzed before the indications for an ADC (from 9.6% before to 74% after; P < .001). The same strategy was applied to the following process parameters: use of a clean work surface, clean withdrawal of equipment from the dressing trolley, and appropriate waste disposal.Conclusions:A PLP sufficiently implemented a standardized concept for aseptic dressing change during an iterative improvement process, which resulted in a significant improvement in hand hygiene and adherence to other specific ADCC process steps.

Introduction: SARS-CoV-2 is mainly transmitted via respiratory ingestion of virus-containing particles. In principle, the likelihood of exposure to infectious particles of any size is increased within a distance of 1-2 m to an infected person. Nurses are particularly at risk of contracting COVID-19 from patients due to the close patient contact and the number of intensive contacts. Objectives: It has not yet been investigated, how long and often nurses are exposed to a close patient contact due to the intensive care during their service. The study aimed to determine the duration and frequency of close patient contacts between nurses and COVID-19 patients during nursing activities. Methods: In the period from 14.12.2020 to 28.02.2021, 12 beds of a COVID-19 pulmonary intensive care unit were equipped with Open Access Bluetooth Low Energy (BLE) transmitters and 12 nurses were equipped with BLE wearables (Clinaris GmbH, Germany) in order to record the frequency and duration of patient contact as well as the distance of nurses to the headboard (face) of the patient bed. For the data evaluation, only the measurement data with at least two directly consecutive (chained) measurement contacts longer than 1 s. and a maximum distance of 1.5 m from the patient's head were considered as relevant. Results: Per eight-hour shift a nurse had an average of 73.6 relevant patient contacts with a mean length of stay of 45.7 s. per contact. The most frequent and longest contacts occurred during the early shift (6:00-14:00 o'clock) with an average number of 87.7 contacts and an average duration of 47.9 s. This was followed by the late shift (14:00- 22:00;85.1 contacts;duration 44.1 s.) and the night shift (22:00-6:00;42.6 contacts;44.6 s.). A nurse was closer than 1.5 m to patients' heads for an average of 60.29 min. per shift. Conclusion: The results show for the first time how many relevant contacts take place when caring for Covid-19 intensive care patients and provide initial indications for assessing the risk of infection in the daily work of intensive care nurses. In general, nurses work approx. 1/8 of their working time closer than 1.5 m to the head area of COVID-19 infected patients and are, directly exposed to SARSCoV- 2 within the typical droplet distance.

Introduction: The mandatory wearing of mouth-nose covers is, in addition to maintaining distance, a central component of the transmission prevention of COVID-19 and is intended to protect potential contact persons from ingesting pathogen-containing material. Objectives: The study examined whether the population's motivation to comply with the oral-nasal coverage requirement was higher immediately after its implementation than in the weeks that followed, as declining coronavirus disease-19 (COVID-19) case rates and the end of the initial lockdown on May 15, 2020, may have led to a decrease in risk awareness and thus noncompliance with the established behavioral rules. Methods: In a covert observational study in mask-required settings (public transportation and retail stores), mask types used and observed mask use errors were recorded over two time periods in a total of 9131 individuals. In addition, the importance of individual mask features, wearing behavior, and reasons for choosing current mouth-to-nose coverage, as well as attitudes toward COVID-19 protective measures, were collected in an online survey. Individuals observed in public and individuals in the online surveys represent two separate cohorts. Results: Over the time (07.05.-13.05.2020/12.06.-08.07.2020), the mask wear adherence increased in from 97.2% to 98.6% (p < 0.001). In addition, a percentage decrease in the number of people without mouth-nose cover (p < 0.001) and an increase in the correct mask application was observed (p = 0.024). In the online survey, 84% of respondents identified comfort/convenience and 81% of respondents identified fit as the most important mask attributes. The reasons for the choice of the mouth-nose cover used were heterogeneous and varied. The respondents stated that they found the wearing of a mouth-nose-covering annoying (57%) but useful (60%), but would not wear a mask if there was no mask obligation or recommendation to wear the masks (67%). Conclusion: Despite improvement, a high frequency of errors (31%) in wearing face masks were still observed, indicating the need for better clarification of the population on the correct wearing of a mask.

Introduction:With the use of elastomeric-half mask respirators in healthcare settings, it has been reported that the verbal communication is decreased or compromised when wearing the masks (Palmiero, Symons, Morgan and Schaffer, 2016).This study examines the communication effectiveness of this innovation (elastomeric reusable respirator) and others in the industry, using speech intelligibility objective scoring, and qualitative research.Objectives: This research measured the acoustical performance, speech transmission index (STI) (Palmeiro, et al., 2016) on an innovative elastomeric respirator, and others utilized in health care, according to IEC 60268-16 Objective rating of speech intelligibility standard.Methods: STI measurements were obtained in a semi-anechoic acoustic test chamber/quiet room with background noise levels of less than 15 dBA.Then higher levels of background noise (57.6 dBA and 72 dBA, Zunn and Downey, 2005) was added to the test room and additional STI tests will be conducted in the presence of these elevated background noise levels.The "voice" signal was emitted by the artificial voice of an acoustic head and torso simulator (HATS) and was one of two types of sound: the STI test waveform or the the Harvard sentences sound waveform (phonetically balanced and very clearly spoken human speech).The background noise portion, when used, was added separately by a high fidelity loudspeaker.The speech and STI waveform sounds were produced inside the test room at the sound level of 60 dBA (1 m microphone distance). Results:In an environment with no background noise, the innovation of the re-usable elastomeric respirator, yielded the highest STI rating compared to other elastomeric respirators (0.90-0.91) or excellent rating.Other elastomeric respirators tested, showing fair, to low excellent range.The re-usable elastomeric respirator innovation had a 0.03 less in speech intelligibility than, single use N95 STI rating.Conclusion: Speech intelligibility is complex, and incorporates subjective (listener) criteria, objective speech intelligibility, and background noise, as well as the environment.Additional subjective testing, with the recorded sound files, with a randomized control clinical trial would benefit this research.

INTRODUCTION:The German Commission for Hospital Hygiene and Infection Prevention recommends nominating one authorized medical specialist in every medical department as an infection prevention link physician (PLP). It has been roughly described that a PLP serves as a link between the infection prevention team and the respective clinical departments. No detailed evidence about the contribution made by PLPs to the decrease of infection rates is available in Germany. The "HygArzt" project aims to demonstrate the medical and economic benefits of the implementation of hygiene measures by PLP in trauma surgery/orthopedics. METHODS:A multicenter interventional pre/post cohort study design was chosen. The study will run for a three-year period, including a pre-, post-, and an intervention phase, in four different hospitals, one of which will serve as pilot. A complex intervention containing evidence-based infection control measures will be developed and implemented by a PLP to proof efficacy. After the successful implementation of the preventive measures in the pilot hospital, the concept will be transposed to the three remaining trauma and orthopedic departments to confirm the transferability and generalizability. To enable the PLPs of the non-pilot departments, a subject-specific training program will be developed based on the study results of the pilot hospital and offered to the PLPs. DISCUSSION:Data are intended to provide evidence that and, if so, to which extent the implementation of specific preventive measures by a medical department-specific PLP is possible and results in a reduction of nosocomial infections in orthopedic surgery and traumatology. CONTRIBUTION TO THE LITERATURE:The present study describes a novel complex study design to prove the effectiveness of intervention measures for infection prevention. The study design and newly developed methodological approach could serve as a model for similar studies on infection prevention in the future. For the first time, the presented research project "HygArzt" focuses on the implementation of hygiene measures by an infection prevention link physician (PLP) and investigates whether nosocomial infections, especially surgical site infections, can be reduced by the measures implemented. TRIAL REGISTRATION:German clinical Trials register DRKS-ID:00013,296. Registered on March 5, 2018, https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00013296.

Die COVID-19 Pandemie hat erhebliche gesellschaftliche Auswirkungen. Die Transmissionsvorbeugung in der Bevölkerung beinhaltet u. a. das Tragen von textilen Mund-Nasen-Bedeckungen. Voraussetzung des Schutzeffekts ist der korrekte Maskeneinsatz, wobei Anwendungsfehler selbst unter medizinischem Fachpersonal beobachtet wurden. In der vorliegenden Arbeit wurde analysiert, welche Masken im öffentlichen Raum als Mund-Nasen-Bedeckung zum Einsatz kamen, ob der Einsatz korrekt erfolgte und welcher Art die beobachteten Anwendungsfehler waren. Es erfolgte eine prospektive Beobachtungsstudie in Bereichen, für die eine textile Mund-Nasen-Bedeckungspflicht nach der Coronaschutzverordnung NRW galt. Zwischen dem 07.05.2020 und 13.05.2020 wurden 2721 Personen in maskenpflichtigen Bereichen beobachtet. Die Gesamtcompliance zu Mund-Nasen-Bedeckungen betrug 97,2%. Am häufigsten kam der chirurgische Mund-Nasen-Schutz (MNS) (44,9%) zum Einsatz, gefolgt von Stoffmasken (39,8%), FFP-Masken (7,1%) sowie Schals (5,4%). Keine Maske trugen 2,8% der Beobachteten. In 30,4% der Fälle wurde die Mund-Nasen-Bedeckung fehlerhaft getragen. Die häufigsten Anwendungsfehler fielen in die Kategorien „Maske unter der Nase getragen“ (41,4%) und „Nasenbügel nicht angepasst“ (20,8%). Der MNS wurden deutlich häufiger fehlerhaft eingesetzt als die übrigen Masken- Typen (p<0,001). In der vorliegenden Untersuchung zeigte sich eine hohe Gesamtcompliance der Bevölkerung von 97% zum Einsatz von Mund-Nasen-Bedeckungen im Rahmen des COVID-19 Pandemie- Managements. Die Masken wurden in 30% der Fälle fehlerhaft genutzt. Hieraus ergibt sich die Notwendigkeit einer gezielten, intensivierten Wissensvermittlung zur Maskenanwendung an die Bevölkerung, die die beobachteten Defizite berücksichtigt.

(1) To compare the incidence of post-operative septic arthritis following anterior cruciate ligament reconstruction (ACLR) between patients receiving routine pre-operative intravenous (IV) prophylaxis only intravenous (IV) infection prophylaxis and patients receiving additional graft-soaking in a vancomycin solution (5 mg/ml) perioperatively. (2) To review the literature regarding effects of graft-soaking in vancomycin solutions on outcomes, complication rates and tendon properties in ACLR.

Für die Therapie von Infektionen mit multiresistenten gramnegativen Bakterien (MRGN) stehen nur wenige Antibiotika zur Verfügung. Dem Management von Patienten mit MRGN-Kolonisation bzw. -Infektion kommt daher eine herausragende Bedeutung bezüglich postoperativer Morbidität und Mortalität zu.

There are several hints that bacterial colonization might be an often overseen cause of non-union. Modern procedures like PCR have been reported to diagnose bacterial colonization with a high degree of accuracy. While PCR is not ubiquitously available, we hypothesize that biopsies from the non-union site are comparable to PCR results reported in the literature.