Historic methicillin-resistant Staphylococcus aureus: expanding current knowledge using molecular epidemiological characterization of a Swiss legacy collection.

BACKGROUND: Few methicillin-resistant Staphylococcus aureus (MRSA) from the early years of its global emergence have been sequenced. Knowledge about evolutionary factors promoting the success of specific MRSA multi-locus sequence types (MLSTs) remains scarce. We aimed to characterize a legacy MRSA collection isolated from 1965 to 1987 and compare it against publicly available international and local genomes. METHODS: We accessed 451 historic (1965-1987) MRSA isolates stored in the Culture Collection of Switzerland, mostly collected from the Zurich region. We determined phenotypic antimicrobial resistance (AMR) and performed whole genome sequencing (WGS) using Illumina short-read sequencing on all isolates and long-read sequencing on a selection with Oxford Nanopore Technology. For context, we included 103 publicly available international assemblies from 1960 to 1992 and sequenced 1207 modern Swiss MRSA isolates from 2007 to 2022. We analyzed the core genome (cg)MLST and predicted SCCmec cassette types, AMR, and virulence genes. RESULTS: Among the 451 historic Swiss MRSA isolates, we found 17 sequence types (STs) of which 11 have been previously described. Two STs were novel combinations of known loci and six isolates carried previously unsubmitted MLST alleles, representing five new STs (ST7843, ST7844, ST7837, ST7839, and ST7842). Most isolates (83% 376/451) represented ST247-MRSA-I isolated in the 1960s, followed by ST7844 (6% 25/451), a novel single locus variant (SLV) of ST239. Analysis by cgMLST indicated that isolates belonging to ST7844-MRSA-III cluster within the diversity of ST239-MRSA-III. Early MRSA were predominantly from clonal complex (CC)8. From 1980 to the end of the twentieth century, we observed that CC22 and CC5 as well as CC8 were present, both locally and internationally. CONCLUSIONS: The combined analysis of 1761 historic and contemporary MRSA isolates across more than 50 years uncovered novel STs and allowed us a glimpse into the lineage flux between Swiss-German and international MRSA across time.

Patients exposed to vancomycin-resistant enterococci during in-hospital outbreaks in a low endemic setting: a proposal for risk-based screening.

BACKGROUND: The optimal extent of screening of contact patients (CoPat) after exposure to patients infected or colonized with vancomycin-resistant enterococci (VRE) remains controversial. METHODS: We retrospectively developed a new risk stratification for screening patients exposed to VRE, based on data from three outbreaks-two with Enterococcus faecium vanB and one with Enterococcus faecium vanA involving 1096 CoPat-in a low endemic setting. We classified them into four risk groups: three on environmental exposure, one by healthcare exposure: high (sharing the same room/bathroom with a VRE-colonized patient), medium (hospitalization in the same room after a VRE-colonized patient's discharge until terminal disinfection including ultraviolet C (UVc)-disinfection), low (hospitalized in the same room within three weeks before the VRE-colonized patient), and "staff" (screening of patients having the same medical care team). RESULTS: VRE-transmission occurred in 7.9% in the high-risk group compared to 0.6% and 0% in the medium and low risk groups. There was a significant trend to higher rates of transmission by risk level of exposure (p < 0.001). In the "staff" group, VRE transmission rate was 2.3%. CONCLUSION: Based on this stratification, we recommend to focus screening of exposed CoPat on the high-risk and "staff" group, saving resources and costs, but larger studies will allow to further improve the yield of VRE screening in the outbreak setting.

Long-term antimicrobial effectiveness of a silver-impregnated foil on high-touch hospital surfaces in patient rooms.

BACKGROUND: The hospital environment has got more attention as evidence as source for bacterial transmission and subsequent hospital-acquired infection increased. Regular cleaning and disinfection have been proposed to lower the risk of infection, in particular for gram-positive bacteria. Auto-disinfecting surfaces would allow to decrease survival of pathogens, while limiting resource to achieve a safe environment in patient rooms. METHODS: A controlled trial to evaluate the antimicrobial effectiveness of a polyvinyl chloride foil containing an integrated silver-based agent (containing silver ions 2%) on high-touch surfaces in patient rooms. RESULTS: The overall log reduction of the mean values was 1.8 log10 CFU, the median 0.5 log10 CFU comparing bioburden of control vs antimicrobial foil (p < 0.01). Important pathogens were significantly less likely recovered from the foil, in particular enterococci. These effects were present even after 6 months of in-use. CONCLUSIONS: A foil containing an integrated silver-based agent applied to high-touch surfaces effectively results in lower recovery of important pathogens from such surfaces over a 6-month study period.

Handrub dispensers per acute care hospital bed: a study to develop a new minimum standard.

BACKGROUND: Accessibility to alcohol-based handrub (ABHR) dispenser is crucial to improve compliance to hand hygiene (HH), being offered as wall-mounted dispensers (ABHR-Ds), and/or pocket bottles. Nevertheless, information on the distribution and density of ABHR-Ds and their impact on HH have hardly been studied. Institutions such as the World Health Organisation or the Centers for Disease Control and Prevention do not provide guidance. The Robert-Koch-Institute (RKI) from Germany recommends an overall density of > 0.5 dispensers per patient bed. We aimed to investigate current conditions in hospitals to develop a standard on the minimal number of ABHR-D. METHODS: Between 07 and 09/2019, we applied a questionnaire to 178 hospitals participating in the Swissnoso National Surveillance Network to evaluate number and location of ABHR-Ds per bed in acute care hospitals, and compared the data with consumption and compliance with HH. RESULTS: 110 of the 178 (62%) hospitals provided data representing approximately 20,000 hospital beds. 83% hospitals provided information on both the total number of ABHR-Ds and patient beds, with a mean of 2.4 ABHR-Ds per bed (range, 0.4-22.1). While most hospitals (84%) had dispensers located at the room entrance, 47% reported also locations near or at the bed. Additionally, pocket-sized dispensers (100 mL) are available in 97% of hospitals. CONCLUSIONS: Swiss hospitals provide 2.4 dispensers per bed, much more than governmental recommendation. The first study on the number of ABHR-Ds in hospitals may help to define a minimal standard for national and international recommendations.

Multicenter Prevalence Study Comparing Molecular and Toxin Assays for Clostridioides difficile Surveillance, Switzerland.

Public health authorities in the United States and Europe recommend surveillance for Clostridioides difficile infections among hospitalized patients, but differing diagnostic algorithms can hamper comparisons between institutions and countries. We compared surveillance based on detection of C. difficile by PCR or enzyme immunoassay (EIA) in a nationwide C. difficile prevalence study in Switzerland. We included all routinely collected stool samples from hospitalized patients with diarrhea in 76 hospitals in Switzerland on 2 days, 1 in winter and 1 in summer, in 2015. EIA C. difficile detection rates were 6.4 cases/10,000 patient bed-days in winter and 5.7 cases/10,000 patient bed-days in summer. PCR detection rates were 11.4 cases/10,000 patient bed-days in winter and 7.1 cases/10,000 patient bed-days in summer. We found PCR used alone increased reported C. difficile prevalence rates by <80% compared with a 2-stage EIA-based algorithm.

Are three antiseptic paints needed for safe preparation of the surgical field? A prospective cohort study with 239 patients.

BACKGROUND: Preoperative skin antisepsis is an essential component of safe surgery. However, it is unclear how many antiseptic paints are needed to eliminate bacteria prior to incision. This study compared microbial skin counts after two and three antiseptic paints. METHODS: We conducted a prospective cohort study in non-emergency patients receiving a cardiac/abdominal surgery with standardized, preoperative skin antisepsis consisting of an alcoholic compound and either povidone iodine (PI) or chlorhexidine (CHX). We obtained three skin swabs from the participant's thorax/abdomen using a sterile template with a 25 cm2 window: After collection of the first swab prior to skin antisepsis, and once the second and third application of PI/CHX had dried out, we obtained a second and third swab, respectively. Our primary outcome was the reduction in microbial skin counts after two and three paints of PI/CHX. RESULTS: Among the 239 enrolled patients, there was no significant difference in the reduction of mean square root-transformed microbial skin counts with three versus two paints (P = 0.2). But distributions of colony forming units (CFUs) decreased from paint 2 to 3 in a predefined analysis (P = 0.002). There was strong evidence of an increased proportion of patients with zero CFU after paint 3 versus paint 2 (P = 0.003). We did not identify risk factors for insufficient reduction of microbial skin counts after two paints, defined as the detection of > 5 CFUs and/or ≥ 1 pathogens. CONCLUSIONS: In non-emergency surgical patients, three antiseptic paints may be superior to two paints in reducing microbial skin colonization prior to surgery.

Relevance of Dermabacter hominis isolated from clinical samples, 2012-2016: a retrospective case series.

We investigated the clinical relevance of Dermabacter hominis isolated from samples of 108 patients. Polymicrobial growth was evident in 88% of specimens. Isolation of D. hominis was of definitive or possible significance in only 14% of patients. Vancomycin remains the drug of choice given a penicillin resistance rate of 84%.

Impact of alcohol-based hand-gel sanitizer and hand hygiene advice on travellers' diarrhoea and colonization with extended-spectrum beta-lactamase-producing Enterobacteriaceae: A randomised, controlled trial.

BACKGROUND: Travellers' diarrhoea (TD) is the most common health problem in international travellers. Besides being bothersome for the individual and a considerable economic burden for the public, TD is also known to be associated with becoming colonized with extended-spectrum ß-lactamase (ESBL)-producing Enterobacteriacea. Despite the high frequency of TD cases, easy and effective preventive measures are lacking. The aim of this study was to assess the impact of using hand gel sanitizer on the incidence of TD and colonization with ESBL-producing Enterobacteriaceae. METHOD: A multicentre randomized intervention trial studying the effect of hand gel sanitizer on the incidence of TD and colonization with ESBL-producing Enterobacteriaceae in travellers to Southeast Asia was performed. RESULTS: The intention to treat analysis showed a reduction in the incidence of WHO TD in the intervention group (OR 0.54 (95% CI 0.30-0.97), p = 0.04). No effect was seen or the incidence of becoming colonized with ESBL-producing Enterobacteriaceae. CONCLUSION: Using hand gel sanitizer might have a protective effect on the occurrence of TD. Based on the current data, education on the proper use appears to play a key role for its effectiveness.

Vaginal-perineal cultures for detecting group B streptococci and extended spectrum ß-lactamase producing bacteria in pregnancy.

OBJECTIVE: To compare the detection rates of vaginal-perineal cultures for group B streptococci (GBS) with the standard vaginal and rectal cultures and evaluate the diagnostic yield of vaginal-perineal vs. rectal swabs for extended spectrum ß-lactamase producing Enterobacterales (ESBL-E) during the third trimester of pregnancy. STUDY DESIGN: Vagino-perineal and rectal swabs were collected cross-sectionally from pregnant women between 35-37 weeks gestation and tested for the presence of GBS and ESBL-E. Accuracy of the vagino-perineal swab was compared to the combined vagino-perineal/rectal swab. Risk factors for ESBL carriage were examined. Degrees of pain, discomfort and stress related to the rectal swab were analyzed on visual analogue scales. RESULTS: 48 out of 250 participants (19.2%) were GBS positive. The vagino-perineal swab was positive in 44 of 48 women (91.7%) yielding a negative predictive value of 98.1%. Agreement (kappa) between the two methods was 0.95. Six out of 190 women with additional ESBL-E screening (3.2%) tested positive by rectal swab. Of these, only two had also a positive vagino-perineal swab. The rectal swab caused overall little subjective discomfort, pain or stress, as indicated by low scores indicated on the visual scales. CONCLUSIONS: The GBS detection rate of the vagino-perineal swab was lower compared to the reference standard. However, agreement between the two screening methods was high and there were no cases of GBS neonatal sepsis in the recruited population, supporting this less invasive screening strategy. In contrast, the vaginal-perineal swab was inferior to the rectal swab for detecting ESBL-E, indicating that this less invasive method for detecting antibiotic resistant bacteria that may be potentially transferred to the neonate during labor and delivery would be inappropriate for ESBL-E screening in pregnant women. The low ESBL-E carriage rate among pregnant women likely reflects the prevalence in the general population.

ESBL-colonization at ICU admission: impact on subsequent infection, carbapenem-consumption, and outcome.

OBJECTIVE: To determine whether colonization with extended-spectrum ß-lactamase-producing Enterobacteriaceae (ESBL-PE) predicts the risk for subsequent infection and impacts carbapenem-consumption and outcome in intensive care unit (ICU) patients. DESIGN: Prospective cohort study. SETTING: The 2 ICUs in the University Hospital Basel in Switzerland. PATIENTS: All patients admitted to the 2 ICUs providing mechanical ventilation and an expected ICU stay >48 hours. METHODS: Patients were routinely screened for ESBL-PE carriage by rectal swab on admission. Competing risk regression analyses were applied to calculate hazard ratios (HRs) for infection with ESBL-PE and mortality. Length of hospital stay, length of ICU stay, and duration of carbapenem exposure were compared using the Mann-Whitney U test. RESULTS: Among 302 patients, 24 (8.0%) were colonized with ESBL-PE on ICU admission. Infections with ESBL-PE occurred in 4 patients, of whom 3 (75%) were identified as ESBL-PE colonized on admission. ESBL-PE colonization on admission was associated with subsequent ESBL-PE infection (hazard ratio [HR], 25.52; 95% confidence interval [CI], 2.40-271.41; P = .007) and exposure to carbapenems (HR, 2.42; 95% CI, 1.01-5.79; P = .047), whereas duration of carbapenem exposure did not differ in relation to ESBL-PE colonization (median, 7 days [IQR, 3-8 days] vs median, 6 days [IQR 3-9 days]; P = 0.983). Patients colonized with ESBL-PE were not at increased risk for death overall (HR, 1.00; 95% CI, 0.44-2.30; P = .993) or death attributable to infection (HR, 1.20; 95% CI, 0.28-5.11; P = .808). CONCLUSIONS: Screening strategies for detection of ESBL-PE colonization on ICU admission may allow the identification of patients at highest risk for ESBL-PE infection and the correct allocation of empiric carbapenem treatment.

Simplifying the World Health Organization Protocol: 3 Steps Versus 6 Steps for Performance of Hand Hygiene in a Cluster-randomized Trial.

BACKGROUND: In an experimental setting, a simplified, 3-step hand hygiene technique for applying alcohol-based hand rub was non inferior in terms of reduction of bacterial counts, as compared to the conventional World Health Organization 6-step technique. We therefore compared compliance and microbiological efficacy between both hand hygiene techniques in routine clinical practice. METHODS: We performed a cluster-randomized trial from October-November 2015 at the University Hospital Basel, Switzerland: a tertiary, academic care center (ISRCTN45923734). We randomly assigned 12 wards to either the 3-step technique or the conventional 6-step technique of hand rubbing. The primary endpoints were compliance with the assigned technique and reduction of bacterial counts on the hands of health-care workers. RESULTS: Overall, 2923 hand hygiene indications were observed, and compliance was 70.7% (2066/2923). Compliance with technique and indications was 51.7% (595/1151) and 75.9% (1151/1516) on wards assigned to the 3-step technique, respectively, as compared to 12.7% (116/915) and 65.0% (915/1407) on wards assigned to the 6-step technique (P < .001). The reduction factor (RF) of bacterial colony counts did not differ between techniques (median RF 0.97 log10 colony-forming units [CFU] [interquartile range 0.39-1.59] for the 3-step technique vs median RF 1.04 log10 CFU [interquartile range 0.49-1.52] for the 6-step technique; P = .629). CONCLUSIONS: In a clinical setting, the simpler hand hygiene technique, consisting of 3 steps, resulted in higher compliance with both hand hygiene indications and technique, as compared to the 6 steps. As the results of the microbiological analyses exclude inferiority, the conventional 6 steps could be safely replaced by a simpler hand hygiene technique. CLINICAL TRIALS REGISTRATION: ISRCTN45923734.

Basic patient characteristics predict antimicrobial resistance in E. coli from urinary tract specimens: a retrospective cohort analysis of 5246 urine samples.

BACKGROUND: Antimicrobial resistance data from surveillance networks are frequently do not accurately predict resistance patterns of urinary tract infections at the bedside. OJECTIVE: To determine simple patient- and institution-related risk factors affecting antimicrobial resistance patterns of Escherichia coli urine isolates. METHODS: From January 2012 to May 2015 all consecutive urine samples with significant growth of E. coli (≥103 CFU/ml) obtained from a tertiary care hospital were analysed for antimicrobial susceptibility and related to basic clinical data such a patient age, ward, sample type (catheter vs non-catheter urine). RESULTS: Antimicrobial susceptibility testing was available for 5246 E. coli urine isolates from 4870 patients. E. coli was most commonly resistant to amoxicillin (43.1%), cotrimoxazole (24.5%) and ciprofloxacin (17.4%). Resistance rates were low for meropenem (0.0%), fosfomycin (0.9%) and nitrofurantoin (1.5%). Significantly higher rates of resistance to ciprofloxacin (32.8 vs 15.8%) and cotrimoxazole (30.6 vs 23.9%) were found in urological patients compared with patients on other wards (p <0.01). In multivariable analysis, predictors for E. coli resistance against ciprofloxacin and cotrimoxazole were: treatment in the urological unit (odds ratio [OR] 2.04, 95% confidence interval [CI] 1.63-2.54; p <0.001 and OR 1.33, 95% CI 1.07-1.64; p = 0.010, respectively), male sex (OR 1.93, 95% CI 1.630-2.29; p <0.001 and OR 1.22, 95% CI 1.22-1.04; p = 0.015), and only to a lesser extent urine samples obtained from indwelling catheters (OR 1.30, 95% CI 1.05-1.61; p = 0.014 and OR 1.26, 95% CI 1.04-1.53; p = 0.020). Age ≥65 years was associated with higher resistance to ciprofloxacin (OR 1.42, 95% CI 1.21-1.67; p <0.001), but lower resistance to cotrimoxazole (OR 0.76, 95% CI 0.67-0.86; p <0.001). CONCLUSIONS: Simple bedside patient data such as age, sex and treating hospital unit help to predict antimicrobial resistance and can improve the empirical treatment of urinary tract infections.

Combination therapy for treatment of Pseudomonas aeruginosa bloodstream infections.

OBJECTIVES: Management of bloodstream infections ("BSIs") caused by Pseudomonas aeruginosa remains controversial as data supporting the use of definite combination treatment for severe P. aeruginosa infections remain conflicting. We aimed to determine differences in mortality between patients treated with definite combination therapy and monotherapy in a large 11-year cohort. METHODS: All consecutive patients with P. aeruginosa BSI hospitalized at the University Hospital Basel, Switzerland, a tertiary academic care center, from January 2003 to December 2013 were included. Pertinent clinical data was assessed. Patients with and without definite combination therapy were compared and hazard ratios for death were calculated. RESULTS: During the study period, 187 patients with P. aeruginosa BSI were identified. Definite combination therapy was administered in 42.8% (80/187) of all patients, of which 76% (61/80) received a combination of a betalactam with an aminoglycoside and 24% (19/80) received a combination of a betalactam with a quinolone. The remaining 57.2% (107/187) were treated with betalactam monotherapy. Median treatment duration was 15 days (interquartile range 12-20 days). Mortality was lower in patients receiving definite combination therapy in univariable and multivariable cox regression analyses (HR 0.26, 95% CI 0.11-0.60, p = 0.002 and HR 0.30, 95% CI 0.13-0.71, p = 0.006, respectively), the latter adjusting for age, neutropenia at diagnosis, PITT bacteremia score, and inadequate empirical treatment. CONCLUSIONS: Combination therapy (i.e. betalactam-aminoglycoside or betalactam-quinolone combinations) may improve survival of P. aeruginosa BSI, independent of potential confounders such as age, neutropenia, PITT bacteremia score, and inadequate empirical treatment.

Different Types of Heater-Cooler Units and Their Risk of Transmission of Mycobacterium chimaera During Open-Heart Surgery: Clues From Device Design.

OBJECTIVEWorldwide, Mycobacterium chimaera infections have been linked to contaminated aerosols from heater-cooler units (HCUs) during open-heart surgery. These infections have mainly been associated with the 3T HCU (LivaNova, formerly Sorin). The reasons for this and the risk of transmission from other HCUs have not been systematically assessed.DESIGNProspective observational study.SETTINGUniversity Hospital Basel, Switzerland.METHODSContinuous microbiological surveillance of 3 types of HCUs in use (3T from LivaNova/Sorin and HCU30 and HCU40 from Maquet) was initiated in June 2014, coupled with an epidemiologic workup. Monthly water and air samples were taken. Construction design was analyzed, and exhausted airflow was measured.RESULTS Mycobacterium chimaera grew in 8 of 12 water samples (66%) and 22 of 24 air samples (91%) of initial 3T HCUs in use, and in 2 of 83 water samples (2%) and 0 of 41 (0%) air samples of new replacement 3T HCUs. Moreover, 7 of 12 water samples (58%) and 0 of 4 (0%) air samples from the HCU30 were positive, and 0 of 64 (0%) water samples and 0 of 50 (0%) air samples from the HCU40 were positive. We identified 4 relevant differences in HCU design compared to the 3T: air flow direction, location of cooling ventilators, continuous cooling of the water tank at 4°C, and an electronic alarm in the HCU40 reminding the user of the next disinfection cycle.CONCLUSIONSAll infected patients were associated with a 3T HCU. The individual HCU design may explain the different risk of disseminating M. chimaera into the air of the operating room. These observations can help the construction of improved devices to ensure patient safety during cardiac surgery.Infect Control Hosp Epidemiol 2018;834-840.

Correction to: Catheter retention as a consequence rather than a cause of unfavorable outcome in candidemia.

In the original publication the members of the FUNGINOS network were provided in such a way that they could not be indexed as collaborators on PubMed.

High prevalence of ESBL-Producing E. coli in private and shared latrines in an informal urban settlement in Dar es Salaam, Tanzania.

Background: Data about the burden of extended-spectrum beta-lactamase (ESBL)-producing microorganisms in Africa are limited. Our study aimed to estimate the prevalence of human faecal ESBL carriage in the community of an informal urban settlement in Dar es Salaam (Tanzania, East Africa) by using environmental contamination of household latrines with ESBL as a surrogate marker. Methods: Within the context of a large survey in February 2014 assessing 636 randomly selected household latrines for faecal contamination by the detection of growth of E. coli and total faecal coliform bacteria, a randomly selected subset of the samples were screened for ESBL. Results: Seventy latrines were screened for ESBL. An average of 11.4 persons (SD ±6.5) were sharing one latrine. Only three (4.3%) latrines had hand-washing facilities and 50 showed faeces on the floor. ESBL-producing Enterobacteriaceae were confirmed in 17 (24.3%) of the 70 latrine samples: 16 E. coli and 1 Klebsiella pneumoniae. Five ESBL E. coli strains were detected on door handles. The most prevalent ESBL type was CTX-M-1 group (76.5%). Pulsed-field gel electrophoresis typing of a subset of ESBL-producing E. coli isolates revealed both diverse singular types and a cluster of 3 identical isolates. There was no significant difference of the latrine and household characteristics between the group with ESBL (n = 17) and the group with non-ESBL E. coli (n = 53) (p > 0.05). Conclusions: Almost a quarter of private and shared latrines in an informal urban settlement in Tanzania are contaminated with ESBL-producing microorganisms, suggesting a high prevalence of human ESBL faecal carriage in the community. Shared latrines may serve as a reservoir for transmission in urban community settings in Tanzania.

Fluconazole non-susceptible breakthrough candidemia after prolonged low-dose prophylaxis: a prospective FUNGINOS study.

OBJECTIVES: Breakthrough candidemia (BTC) on fluconazole was associated with non-susceptible Candida spp. and increased mortality. This nationwide FUNGINOS study analyzed clinical and mycological BTC characteristics. METHODS: A 3-year prospective study was conducted in 567 consecutive candidemias. Species identification and antifungal susceptibility testing (CLSI) were performed in the FUNGINOS reference laboratory. Data were analyzed according to STROBE criteria. RESULTS: 43/576 (8%) BTC occurred: 37/43 (86%) on fluconazole (28 prophylaxis, median 200 mg/day). 21% BTC vs. 23% non-BTC presented severe sepsis/septic shock. Overall mortality was 34% vs. 32%. BTC was associated with gastrointestinal mucositis (multivariate OR 5.25, 95%CI 2.23-12.40, p < 0.001) and graft-versus-host-disease (6.25, 1.00-38.87, p = 0.05), immunosuppression (2.42, 1.03-5.68, p = 0.043), and parenteral nutrition (2.87, 1.44-5.71, p = 0.003). Non-albicans Candida were isolated in 58% BTC vs. 35% non-BTC (p = 0.005). 63% of 16 BTC occurring after 10-day fluconazole were non-susceptible (Candida glabrata, Candida krusei, Candida norvegensis) vs. 19% of 21 BTC (C. glabrata) following shorter exposure (7.10, 1.60-31.30, p = 0.007). Median fluconazole MIC was 4 mg/l vs. 0.25 mg/l (p < 0.001). Ten-day fluconazole exposure predicted non-susceptible BTC with 73% accuracy. CONCLUSIONS: Outcomes of BTC and non-BTC were similar. Fluconazole non-susceptible BTC occurred in three out of four cases after prolonged low-dose prophylaxis. This implies reassessment of prophylaxis duration and rapid de-escalation of empirical therapy in BTC after short fluconazole exposure.

Respiratory Syncytial Virus Infection Control Challenges with a Novel Polymerase Chain Reaction Assay in a Tertiary Medical Center.

OBJECTIVES To evaluate host characteristics, mode of infection acquisition, and infection control procedures in patients with a positive respiratory syncytial virus (RSV) test result after the introduction of the GenXpert Influenza/RSV polymerase chain reaction (PCR) assay. DESIGN Retrospective cohort study. PATIENTS Adults with a positive PCR test result for RSV who were hospitalized in a tertiary academic medical center between January 2015 and December 2016 were included in this study. Our infection control policy applies contact isolation precautions only for immunocompromised patients. METHODS Patients were identified through 2 databases, 1 consisting of patients isolated because of RSV infection and 1 with automatically collected laboratory results. Baseline and clinical characteristics were collected through a retrospective medical chart review. The rate of and clinical factors associated with healthcare-associated RSV infections were evaluated. RESULTS In total, 108 episodes in 106 patients hospitalized with a positive Xpert RSV test result were recorded during the study period. Among them, 11 episodes were healthcare-associated infections (HAIs) and 97 were community-acquired infections (CAIs). The mean length of hospital stay (LOS, 40.2 vs 11.2 days), the mean number of room switches (3.5 vs 1.7) and ward switches (1.5 vs 0.4), and the mean numbers of contact patients (9.9 vs 3.8) were significantly longer and higher in the HAI group than in the CAI group (P<.0001). Surveillance of microbiology records and clinical data did not reveal evidence for a cluster or an epidemic during the 2-year observation period. CONCLUSIONS The introduction of a rapid molecular diagnostic test systematically applied to patients with influenza-like illness may challenge current infection control policies. In our study, patients with HAIs had a prolonged hospital stay and a high number of contact patients, and they switched rooms and wards frequently. Infect Control Hosp Epidemiol 2017;38:1291-1297.