Comparative analysis of sampling and detection methods for fungal contamination on common healthcare environment surface materials.

We evaluated sampling and detection methods for fungal contamination on healthcare surface materials, comparing the efficacy of foam sponges, flocked swabs, and Replicate Organism Detection And Counting (RODAC) plates alongside culture-based quantification and quantitative polymerase chain reaction (qPCR). Findings indicate that sponge sampling and qPCR detection performed best, suggesting a foundation for future studies aiming to surveillance practices for fungi.

Mycobacterium immunogenum acquisition from hospital tap water: a genomic and epidemiologic analysis.

We identified 23 cases of Mycobacterium immunogenum respiratory acquisition linked to a colonized plumbing system at a new hospital addition. We conducted a genomic and epidemiologic investigation to assess for clonal acquisition of M. immunogenum from hospital water sources and improve understanding of genetic distances between M. immunogenum isolates. We performed whole-genome sequencing on 28 M. immunogenum isolates obtained from August 2013 to July 2021 from patients and water sources on four intensive care and intermediate units at an academic hospital. Study hospital isolates were recovered from 23 patients who experienced de novo respiratory isolation of M. immunogenum and from biofilms obtained from five tap water outlets. We also analyzed 10 M. immunogenum genomes from previously sequenced clinical (n = 7) and environmental (n = 3) external control isolates. The 38-isolate cohort clustered into three clades with pairwise single-nucleotide polymorphism (SNP) distances ranging from 0 to 106,697 SNPs. We identified two clusters of study hospital isolates in Clade 1 and one cluster in Clade 2 for which clinical and environmental isolates differed by fewer than 10 SNPs and had less than 0.5% accessory genome variation. A less restrictive combined threshold of 40 SNPs and 5% accessory genes reliably captured additional isolates that met clinical criteria for hospital acquisition, but 12 (4%) of 310 epidemiologically unrelated isolate pairs also met this threshold. Core and accessory genome analyses confirmed respiratory acquisition of multiple clones of M. immunogenum from hospital water sources to patients. When combined with epidemiologic investigation, genomic thresholds accurately distinguished hospital acquisition.

Healthcare Provider N95 Respirator Contamination Worn Behind Face Shields With SARS-CoV-2 During Routine Clinical Care of Patients With COVID-19.

N95 respirator contamination with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during clinical care of patients with coronavirus disease 2019 is poorly understood. We performed a prospective observational study on healthcare provider's (HCP's) N95 respirators' and face shields' SARS-CoV-2 contamination during aerosol-generating procedures on SARS-CoV-2-positive patients housed in a COVID-19-specific unit. Medical masks worn on top of HCP's N95 respirators, and under face shields, during study aerosol-generating procedures were used as surrogates to detect contamination to avoid waste. Thirty-three HCPs were studied, and a total of 33 mask and 27 face shields were sampled. Masks were cut into 9 pieces and face shields were sampled twice, front and back, to determine locality of contamination; however, no positive samples were identified using standard polymerase chain reaction techniques with a CT value up to 40. All 9 mask piece samples were then pooled, as were face shield samples, using centrifugal concentration with polyethersulfone membranes. Once pooled and concentrated, overall, 9 (15%) samples were positive via real-time polymerase chain reaction: 5 from masks (15.2%) and 4 from face shields (14.8%).

Identification of carbapenem-resistant organism (CRO) contamination of in-room sinks in intensive care units in a new hospital bed tower.

BACKGROUND: The origins and timing of inpatient room sink contamination with carbapenem-resistant organisms (CROs) are poorly understood. METHODS: We performed a prospective observational study to describe the timing, rate, and frequency of CRO contamination of in-room handwashing sinks in 2 intensive care units (ICU) in a newly constructed hospital bed tower. Study units, A and B, were opened to patient care in succession. The patients in unit A were moved to a new unit in the same bed tower, unit B. Each unit was similarly designed with 26 rooms and in-room sinks. Microbiological samples were taken every 4 weeks from 3 locations from each study sink: the top of the bowl, the drain cover, and the p-trap. The primary outcome was sink conversion events (SCEs), defined as CRO contamination of a sink in which CRO had not previously been detected. RESULTS: Sink samples were obtained 22 times from September 2020 to June 2022, giving 1,638 total environmental cultures. In total, 2,814 patients were admitted to study units while sink sampling occurred. We observed 35 SCEs (73%) overall; 9 sinks (41%) in unit A became contaminated with CRO by month 10, and all 26 sinks became contaminated in unit B by month 7. Overall, 299 CRO isolates were recovered; the most common species were Enterobacter cloacae and Pseudomonas aeruginosa. CONCLUSION: CRO contamination of sinks in 2 newly constructed ICUs was rapid and cumulative. Our findings support in-room sinks as reservoirs of CRO and emphasize the need for prevention strategies to mitigate contamination of hands and surfaces from CRO-colonized sinks.

Racial disparities in Clostridioides difficile testing in three southeastern US hospitals.

OBJECTIVE: To analyze Clostridioides difficile testing in 3 hospitals in central North Carolina to validate previous racial health-disparity findings. METHODS: We completed a retrospective analysis of inpatient C. difficile tests from 2015 to 2021 at 3 university-affiliated hospitals in North Carolina. We calculated the number of C. difficile tests per 1,000 patient days stratified by race: White, Black, and non-White, non-Black (NWNB). We defined a unique C. difficile test as one that occurred in an inpatient unit with a matching laboratory accession ID and on differing calendar days. Tests were evaluated overall, by hospital, by year, and by positivity rate. RESULTS: In total, 35,160 C. difficile tests and 2,571,850 patient days across all 3 hospitals from 2015 to 2021 were analyzed. The median number of C. difficile tests per 1,000 patient days was 13.85 (interquartile range [IQR], 9.88-16.07). Among all C. difficile tests, 5,225 (15%) were positive. White patients were administered more C. difficile tests (14.46 per 1,000 patient days) than Black patients (12.96; P < .0001) or NWNB race patients (10.27; P < .0001). Black patients were administered more tests than NWNB patients (P < .0001). White patients tested positive at a similar rate to Black patients (15% vs 15%; P = .3655) and higher than NWNB individuals (12%; P = .0061), and Black patients tested positive at a higher rate than NWNB patients (P = .0024). CONCLUSION: White patients received more C. difficile tests than Black and NWNB patient groups when controlling for race patient days. Future studies should control for comorbidities and investigate community onset of C. difficile by race and ethnicity.

A cluster of three extrapulmonary Mycobacterium abscessus infections linked to well-maintained water-based heater-cooler devices.

BACKGROUND: Various water-based heater-cooler devices (HCDs) have been implicated in nontuberculous mycobacteria outbreaks. Ongoing rigorous surveillance for healthcare-associated M. abscessus (HA-Mab) put in place following a prior institutional outbreak of M. abscessus alerted investigators to a cluster of 3 extrapulmonary M. abscessus infections among patients who had undergone cardiothoracic surgery. METHODS: Investigators convened a multidisciplinary team and launched a comprehensive investigation to identify potential sources of M. abscessus in the healthcare setting. Adherence to tap water avoidance protocols during patient care and HCD cleaning, disinfection, and maintenance practices were reviewed. Relevant environmental samples were obtained. Patient and environmental M. abscessus isolates were compared using multilocus-sequence typing and pulsed-field gel electrophoresis. Smoke testing was performed to evaluate the potential for aerosol generation and dispersion during HCD use. The entire HCD fleet was replaced to mitigate continued transmission. RESULTS: Clinical presentations of case patients and epidemiologic data supported intraoperative acquisition. M. abscessus was isolated from HCDs used on patients and molecular comparison with patient isolates demonstrated clonality. Smoke testing simulated aerosolization of M. abscessus from HCDs during device operation. Because the HCD fleet was replaced, no additional extrapulmonary HA-Mab infections due to the unique clone identified in this cluster have been detected. CONCLUSIONS: Despite adhering to HCD cleaning and disinfection strategies beyond manufacturer instructions for use, HCDs became colonized with and ultimately transmitted M. abscessus to 3 patients. Design modifications to better contain aerosols or filter exhaust during device operation are needed to prevent NTM transmission events from water-based HCDs.

Disinfection efficacy of Oxivir TB wipe residue on severe acute respiratory coronavirus virus 2 (SARS-CoV-2).

We assessed Oxivir Tb wipe disinfectant residue in a controlled laboratory setting to evaluate low environmental contamination of SARS-CoV-2. Frequency of viral RNA detection was not statistically different between intervention and control arms on day 3 (P=0.14). Environmental contamination viability is low; residual disinfectant did not significantly contribute to low contamination.

Impact of alcohol-based hand-rub disinfection on bacterial bioburden on stethoscopes in a real-world clinical setting.

In this randomized study, use of alcohol-based hand-rub disinfection significantly reduced bacterial bioburden of stethoscopes in routine clinical use. Prior cleaning of stethoscopes on the study day did not affect baseline contamination rates, which suggests that the efficacy of alcohol disinfection is short-lived and may need to be repeated between patients.

Evaluation of hospital blood culture utilization rates to identify opportunities for diagnostic stewardship.

OBJECTIVES: To evaluate the pattern of blood-culture utilization among a cohort of 6 hospitals to identify potential opportunities for diagnostic stewardship. METHODS: We completed a retrospective analysis of blood-culture utilization during adult inpatient or emergency department (ED) encounters in 6 hospitals from May 2019 to April 2020. We investigated 2 measures of blood-culture utilization rates (BCURs): the total number of blood cultures, defined as a unique accession number per 1,000 patient days (BCX) and a new metric of blood-culture events per 1,000 patient days to account for paired culture practices. We defined a blood-culture event as an initial blood culture and all subsequent samples for culture drawn within 12 hours for patients with an inpatient or ED encounter. Cultures were evaluated by unit type, positivity and contamination rates, and other markers evaluating the quality of blood-culture collection. RESULTS: In total, 111,520 blood cultures, 52,550 blood culture events, 165,456 inpatient admissions, and 568,928 patient days were analyzed. Overall, the mean BCUR was 196 blood cultures per 1,000 patient days, with 92 blood culture events per 1,000 patient days (range, 64-155 among hospitals). Furthermore, 7% of blood-culture events were single culture events, 55% began in the ED, and 77% occurred in the first 3 hospital days. Among all blood cultures, 7.7% grew a likely pathogen, 2.1% were contaminated, and 5.9% of first blood cultures were collected after the initiation of antibiotics. CONCLUSIONS: Blood-culture utilization varied by hospital and was heavily influenced by ED culture volumes. Hospital comparisons of blood-culture metrics can assist in identifying opportunities to optimize blood-culture collection practices.

Evaluation of an Opt-Out Protocol for Antibiotic De-Escalation in Patients With Suspected Sepsis: A Multicenter, Randomized, Controlled Trial.

BACKGROUND: Sepsis guidelines recommend daily review to de-escalate or stop antibiotics in appropriate patients. This randomized, controlled trial evaluated an opt-out protocol to decrease unnecessary antibiotics in patients with suspected sepsis. METHODS: We evaluated non-intensive care adults on broad-spectrum antibiotics despite negative blood cultures at 10 US hospitals from September 2018 through May 2020. A 23-item safety check excluded patients with ongoing signs of systemic infection, concerning or inadequate microbiologic data, or high-risk conditions. Eligible patients were randomized to the opt-out protocol vs usual care. Primary outcome was post-enrollment antibacterial days of therapy (DOT). Clinicians caring for intervention patients were contacted to encourage antibiotic discontinuation using opt-out language. If continued, clinicians discussed the rationale for continuing antibiotics and de-escalation plans. To evaluate those with zero post-enrollment DOT, hurdle models provided 2 measures: odds ratio of antibiotic continuation and ratio of mean DOT among those who continued antibiotics. RESULTS: Among 9606 patients screened, 767 (8%) were enrolled. Intervention patients had 32% lower odds of antibiotic continuation (79% vs 84%; odds ratio, 0.68; 95% confidence interval [CI], .47-.98). DOT among those who continued antibiotics were similar (ratio of means, 1.06; 95% CI, .88-1.26). Fewer intervention patients were exposed to extended-spectrum antibiotics (36% vs 44%). Common reasons for continuing antibiotics were treatment of localized infection (76%) and belief that stopping antibiotics was unsafe (31%). Thirty-day safety events were similar. CONCLUSIONS: An antibiotic opt-out protocol that targeted patients with suspected sepsis resulted in more antibiotic discontinuations, similar DOT when antibiotics were continued, and no evidence of harm. CLINICAL TRIALS REGISTRATION: NCT03517007.

An Enhanced Strategy for Daily Disinfection in Acute Care Hospital Rooms: A Randomized Clinical Trial.

Importance: Environmental contamination is a source of transmission between patients, health care practitioners, and other stakeholders in the acute care setting. Objective: To compare the efficacy of an enhanced daily disinfection strategy vs standard disinfection in acute care hospital rooms. Design, Setting, and Participants: This randomized clinical trial (RCT) was conducted in acute care hospital rooms at Duke University Hospital in Durham, North Carolina, from November 2021 to March 2022. Rooms were occupied by patients with contact precautions. Room surfaces (bed rails, overbed table, and in-room sink) were divided into 2 sides (right vs left), allowing each room to serve as its own control. Each side was randomized 1:1 to the intervention group or control group. Interventions: The intervention was a quaternary ammonium, salt-based, 24-hour continuously active germicidal wipe. It was applied in addition to routine disinfection for the intervention group. The control group received no intervention beyond routine disinfection. Main Outcomes and Measures: The primary outcome was the total contamination, measured in colony-forming units (CFUs) on the bed rails, overbed table, and sink on study day 1. The secondary outcomes were the proportion of sample areas with positive test results for clinically important pathogens, including methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus, and carbapenem-resistant Enterobacteriaceae; the similarity in baseline contamination between sample area sides on study day 0 before application of the intervention, and the proportion of sample areas with removed UV luminescent gel on study day 1. Results: A total of 50 study rooms occupied by 50 unique patients (median [IQR] age, 61 [45-69] years; 26 men [52%]) with contact precautions were enrolled. Of these patients, 41 (82%) were actively receiving antibiotics, 39 (78%) were bedridden, and 28 (56%) had active infections with study-defined clinically important pathogens. On study day 1, the median (IQR) total CFUs for the intervention group was lower than that for the control group (3561 [1292-7602] CFUs vs 5219 [1540-12 364] CFUs; P = .002). On study day 1, the intervention side was less frequently contaminated with patient-associated clinically important pathogens compared with the control side of the room (4 [14%] vs 11 [39%]; P = .04). Conclusions and Relevance: Results of this RCT demonstrated that a quaternary ammonium, salt-based, 24-hour continuously active germicidal wipe decreased the environmental bioburden in acute care hospital rooms compared with routine disinfection. The findings warrant large-scale RCTs to determine whether enhanced daily disinfection strategies can decrease patient acquisition and adverse patient outcomes. Trial Registration: ClinicalTrials.gov Identifier: NCT05560321.

The Impact of Infection Versus Colonization on Clostridioides difficile Environmental Contamination in Hospitalized Patients With Diarrhea.

Background: Patients with Clostridioides difficile infections (CDIs) contaminate the healthcare environment; however, the relative contribution of contamination by colonized individuals is unknown. Current guidelines do not recommend the use of contact precautions for asymptomatic C difficile carriers. We evaluated C difficile environmental contamination in rooms housing adult inpatients with diarrhea based on C difficile status. Methods: We performed a prospective cohort study of inpatient adults with diarrhea who underwent testing for CDI via polymerase chain reaction (PCR) and enzyme immunoassay (EIA). Patients were stratified into cohorts based on test result: infected (PCR+/EIA+), colonized (PCR+/EIA-), or negative/control (PCR-). Environmental microbiological samples were taken within 24 hours of C difficile testing and again for 2 successive days. Samples were obtained from the patient, bathroom, and care areas. Results: We enrolled 94 patients between November 2019 and June 2021. Clostridioides difficile was recovered in 93 (38%) patient rooms: 44 (62%) infected patient rooms, 35 (43%) colonized patient rooms (P = .08 vs infected 38 patient rooms), and 14 (15%) negative patient rooms (P < .01 vs infected; P < .01 vs colonized). Clostridioides difficile was recovered in 40 (56%), 6 (9%), and 20 (28%) of bathrooms, care areas and patient areas in 40 infected patient rooms; 34 (41%), 1 (1%), and 4 (5%) samples in colonized patient rooms; and 12 (13%), 1 (1%), and 3 (3%) of samples in negative patient rooms, respectively. Conclusions: Patients colonized with C difficile frequently contaminated the hospital environment. Our data support the use of contact precautions when entering rooms of patients colonized with C difficile, especially when entering the bathroom.

Severe acute respiratory syndrome coronavirus 2 environmental contamination in hospital rooms is uncommon using viral culture techniques.

We assessed environmental contamination of inpatient rooms housing coronavirus disease 2019 (COVID-19) patients in a dedicated COVID-19 unit. Contamination with severe acute respiratory syndrome coronavirus 2 was found on 5.5% (19/347) of surfaces via reverse transcriptase polymerase chain reaction and 0.3% (1/347) of surfaces via cell culture. Environmental contamination is uncommon in hospitals rooms; RNA presence is not a specific indicator of infectious virus.

Impact of Oral Metronidazole, Vancomycin, and Fidaxomicin on Host Shedding and Environmental Contamination With Clostridioides difficile.

BACKGROUND: Shedding of Clostridioides difficile spores from infected individuals contaminates the hospital environment and contributes to infection transmission. We assessed whether antibiotic selection affects C. difficile shedding and contamination of the hospital environment. METHODS: In this prospective, unblinded, randomized controlled trial of hospitalized adults with C. difficile infection, patients were randomized 1:1:1 to receive fidaxomicin, oral vancomycin, or metronidazole. The primary outcome was change in environmental contamination rate during treatment. Secondary outcomes included stool shedding, total burden of contamination, and molecular relatedness of stool versus environmental C. difficile isolates. RESULTS: Of 33 patients enrolled, 31 (94%) completed the study. Fidaxomicin (-0.36 log10 colony-forming units [CFUs]/d [95% confidence interval (CI), -.52 to -.19]; P < .01) and vancomycin (-0.17 log10 CFUs/d [-.34 to -.01]; P = .05) were associated with more rapid decline in C. difficile shedding than metronidazole (-0.01 log10 CFUs/d [95% CI, -.10 to .08). Both vancomycin (6.3% [95% CI, 4.7-8.3) and fidaxomicin (13.1% [10.7-15.9]) were associated with lower rates of environmental contamination than metronidazole (21.4% [18.0-25.2]). With specific modeling of within-subject change over time, fidaxomicin (adjusted odds ratio, 0.83 [95% CI, .70-.99]; P = .04) was associated with more rapid decline in environmental contamination than vancomycin or metronidazole. Overall, 207 of 233 environmental C. difficile isolates (88.8%) matched patient stool isolates by ribotyping, without significant difference by treatment. CONCLUSIONS: Fidaxomicin, and to a lesser extent vancomycin, reduces C. difficile shedding and contamination of the hospital environment relative to metronidazole. Treatment choice may play a role in reducing healthcare-associated C. difficile transmission. CLINICAL TRIALS REGISTRATION: NCT02057198.

Impact of preoperative chlorhexidine gluconate (CHG) application methods on preoperative CHG skin concentration.

Elective surgical patients routinely bathe with chlorhexidine gluconate (CHG) at home days prior to their procedures. However, the impact of home CHG bathing on surgical site CHG concentration is unclear. We examined 3 different methods of applying CHG and hypothesized that different application methods would impact resulting CHG skin concentration.