Search

Group Name: Duke Center for Antimicrobial Stewardship and Infection PreventionBackground: Wastewater drains in hospital patient rooms have been identified as environmental reservoirs for multidrug-resistant organisms, and they have been linked to outbreaks of carbapenem-resistant Enterobacteriaceae (CRE). We studied the colonization of wastewater drains in a new hospital bed tower. Methods: A patient care unit in a new bed tower opened on July 18, 2020. In-room sinks were located in each hospital room opposite the patient head wall. Patients admitted to this unit underwent weekly rectal cultures to survey for carbapenemase-producing CRE. Additionally, infection preventionists performed routine surveillance of all clinical cultures for CRE. Cultures were performed from all patient room sinks in this unit monthly beginning September 14, 2020. Samples were obtained from the drain cover, handles, and top of bowl using sponges soaked in neutralizing buffer and processed using the stomacher technique. The tail-pipe was sampled using a flocked mini-tip swab soaked in neutralizing buffer; the P-trap water was sampled with sterile tubing attached to a 50-mL syringe. All samples were plated on HARDYCHROM-ESBL and KPC Colorex media and were incubated at 37°C for 24 hours. Results: The first identified CRE-positive patient was admitted to the new unit on December 4, 2020; urine culture obtained at the time of admission grew KPC–producing Klebsiella pneumoniae (KPC-KP). The sink in this patient’s room had been sampled 3 prior times (most recently on November 9, 2020) and was negative for CRE. On December 7, 2020, KPC-KP was found on the drain cover (6,750 colony-forming units, CFU) and in the sink’s P-trap (1,840 CFU) of the index patient’s room during routine sink surveillance. Additional samples from other room surfaces were taken on December 9, 2020, and KPC-KP was recovered from the computer keyboard (452 CFU) and patient bedrails (880 CFU). The patient was discharged from this room December 13, 2020, and the room underwent enhanced terminal room cleaning including UV-C light. On the next routine sink sampling on January 4, 2021, KPC-KP was recovered again in the index room sink P-trap (9,800 CFU) but at no additional sites. MLST was performed, and all isolates were ST-258. Conclusions: In a new bed tower with no prior evidence of CRE-positive patients, the first identified case of a CRE (KPC-KP) in a patient resulted in widespread environmental contamination of the room after only 3 days of hospitalization and contamination of the in-room sink drain that persisted after 1 month. Given the ease with which CRE colonizes wastewater drains, new strategies are needed to mitigate drain colonization and to prevent CRE transmission to subsequent patients.Funding: NoDisclosures: None

Background: We evaluated the impact of a comprehensive SARS-CoV-2 (COVID-19) infection prevention (IP) bundle on rates of non–COVID-19 healthcare-acquired respiratory viral infection (HA-RVI). Methods: We performed a retrospective analysis of prospectively collected respiratory viral data using an infection prevention database from April 2017 to January 2021. We defined HA-RVI as identification of a respiratory virus via nasal or nasopharyngeal swabs collected on or after hospital day 7 for COVID-19 and non–COVID-19 RVI. We compared incident rate ratios (IRRs) of HA-RVI for each of the 3 years (April 2017 to March 2020) prior to and 10 months (April 2020 to January 2021) following full implementation of a comprehensive COVID-19 IP bundle at Duke University Health System. The COVID-19 IP bundle consists of the following elements: universal masking; eye protection; employee, patient, and visitor symptom screening; contact tracing; admission and preprocedure testing; visitor restrictions; discouraging presenteeism; population density control and/or physical distancing; and ongoing attention to basic horizontal IP strategies including hand hygiene, PPE compliance, and environmental cleaning. Results: During the study period, we identified 715 HA-RVIs over 1,899,700 inpatient days, for an overall incidence rate of 0.38 HA-RVI per 1,000 inpatient days. The HA-RVI IRR was significantly higher during each of the 3 years prior to implementing the COVID-19 IP bundle (Table 1). The incidence rate of HA-RVI decreased by 60% after bundle implementation. COVID-19 became the dominant HA-RVI, and no cases of HA-influenza occurred in the postimplementation period (Figure 1). Conclusions: Implementation of a comprehensive COVID-19 IP bundle likely contributed to a reduction in HA-RVI for hospitalized patients in our healthcare system. Augmenting traditional IP interventions in place during the annual respiratory virus season may be a future strategy to reduce rates of HA-RVI for inpatients.

Background Adenoviruses (Adv) are non-enveloped viruses that can survive for long periods on environmental surfaces. However, only 1 prior publication describes an adenovirus pseudo-outbreak associated with bronchoscopes. In 1/ 2020 infectious disease physicians noted a cluster of Adv PCR-positive bronchiolar lavage (BAL) samples, which prompted an outbreak investigation. Methods We reviewed medical charts, clinical microbiology, procedure logs, bronchoscope reprocessing logs, bronchoscope cleaning, and high-level disinfection (HLD) practices. Results On 1/28/20 an infectious diseases physician alerted infection prevention to a cluster of 5 lung transplant patients diagnosed with Adv positive BAL samples. Four out of the 5 patients had the bronchoscopy in the same bronchoscopy suite. We reviewed BAL results from all bronchoscopies performed in this suite from 11/1/19 to 1/24/20 and found a total of 10 patients with positive Adv PCR results. Eight out of the 10 patients had bronchoscopies with one of two bronchoscopes. Of all patients who had a bronchoscopy with the bronchoscope from 11/1/19 to 1/24/20 and had respiratory viral panel sent at that time, 6 of 11 (55%) who underwent procedure with Scope A and 4 of 24 (17%) who underwent procedure with Scope B had positive Adv PCR results. Sham BALs were performed on both bronchoscopes and testing for Adv was negative. However, on inspection by the manufacturer, one scope failed both wet and dry leak tests and had several physical defects. Following removal of both bronchoscopes from service we did not find any positive Adv samples from the bronchoscopy unit. Conclusion Previously, very few pseudo-outbreaks of Adv have been linked to bronchoscopes. We identified a pseudo-outbreak of Adv associated with 2 bronchoscopes in a hospital-based bronchoscopy suite that stopped once we removed the associated bronchoscopes from the procedural unit. Bronchoscopy-related pseudo-outbreaks occur despite standardized procedures for HLD. Bronchoscopy clinics, particularly those with a high volume of immunocompromised patients, should prospectively review BAL cultures to identify unusual pathogen trends. These trends may be a sign of damaged equipment that would otherwise go undetected. Disclosures All Authors: No reported disclosures

Background: The Surgical Care Improvement Project 9 (SCIP 9) mandates the removal of urinary catheters within 48 hours following surgery to reduce the risk of catheter-associated urinary tract infections (CAUTIs). Although patients with thoracic epidurals are not exempt from SCIP 9, these patients may be inherently different from other surgical patients. Early removal of Foley catheters may cause urinary retention and recatheterization, which in turn can lead to CAUTI or urethral trauma. Our hospital’s current policy is to allow Foley catheters to remain in place until the thoracic epidural is removed. The goal of our study was to identify and compare the rate of CAUTI in patients with thoracic epidural catheters to the rate of CAUTI in patients without thoracic epidural catheters Methods: We performed a retrospective cohort study of patients with and without thoracic epidurals who had Foley catheters during hospitalization from July 1, 2017, to May 31, 2019. We used descriptive statistics to compare CAUTI rates based on unit between the 2 groups of patients. Results: We identified 1,834 unique patients with thoracic epidurals and urinary catheters during the study period. We found 4 CAUTIs of 9,896 catheter days (0.4 CAUTIs per 1,000 catheter days) in patients with epidural catheters and 43 CAUTIs of 36,809 catheter days (1.17 CAUTI per 1,000 catheter days) in patients without thoracic epidurals for a rate ratio of 0.346 (95% CI, 0.1242– 0.9639; P < .03). We conducted a sensitivity analysis on a subset of patients admitted under the cardiothoracic service and compared the patients with Foley catheters with and without thoracic epidurals. In this subset, we found 1 CAUTI in 5,890 catheter days (0.17 CAUTI per 1,000 catheter days) in patients with thoracic epidurals and 4 CAUTIs in 9,429 catheter days (0.42 CAUTIs per 1,000 catheter days) in patients without thoracic epidurals), for a rate of 0.4002 (95% CI, 0.0447–3.5808; P < .39). In this subgroup, 7.0% of patients with thoracic epidurals required a second Foley catheter compared to 16.9% of patients without thoracic epidurals who required a second Foley catheter (P < .01). Conclusions: Although patients with thoracic epidurals maintain Foley catheters beyond 48 hours, the CAUTI rate in these patients is lower than in patients without thoracic epidurals. Therefore, removing Foley catheters within 48 hours of surgery in patients with thoracic epidurals may not reduce the risk of CAUTI and, in fact, could be harmful. Further evaluation of confounding variables is warranted.Funding: NoneDisclosures: None

Background C. difficile remains the single most common pathogen among healthcare-associated infections. We conducted a multi-center, prospective study using on-site, near real-time root cause analyses to identify opportunities for reducing hospital-onset C. difficile infection rates (HO-CID). Methods This prospective cohort study enrolled inpatients with HO-CDI admitted to one of 20 participating hospitals in the southeastern United States from July 2019 to June 2020. For each HO-CDI case, mini root cause analyses were conducted by on-site physicians, infection preventionists, or stewardship pharmacists to assess appropriateness of C. difficile testing and inpatient antibiotic use from the 30 days preceding HO-CDI diagnosis. Results The cohort captured 554 total HO-CDI cases and 956 antibiotic use events. 147 (26.5%) of HO-CDI cases were adjudicated as likely inappropriate and a further 51 (9.2%) as potentially inappropriate. Among inappropriately tested cases, 103 (52.0%) had received either laxatives or tube feeds in the preceding 48 hours. 132 (13.8%) of antibiotic use events were identified as potentially inappropriate. Among potentially inappropriate antibiotic use events, 40 (30.3%) received unnecessarily broad-spectrum antibiotics, 20 (15.2%) lacked a confirmed infectious diagnosis, and 4 (3.0%) received a longer than guideline-recommended duration. Risk of inappropriate antibiotic use varied by infection type, with treatment of urinary tract infection being associated with the highest risk of inappropriate antibiotic use (table 1). Table 1: Relative Risk of Inappropriate Antibiotic Use by Indication Conclusion Mini root cause analyses may be a helpful tool for identifying -specific opportunities to reduce HO-CDI rates. We found a high rate of inappropriate testing, usually related to alternative causes for diarrhea such as laxative receipt or tube feeds. While rates of inappropriate antibiotic use were lower than has been reported elsewhere, the majority of opportunities for improvement related to overly broad-spectrum coverage. Urinary tract infections were most strongly associated with inappropriate antibiotic use preceding HO-CDI. Disclosures All Authors: No reported disclosures

Background: Reflex urine cultures (RUCs) have the potential to reduce unnecessary urine cultures and antibiotic use. However, urinalysis parameters that best predict true infection are unknown. In this study, we surveyed different RUC practices in laboratories across a regional network of community hospitals. Methods: We conducted a voluntary electronic survey of infection preventionists to describe laboratory practices relating to RUCs across 51 community hospitals in the Duke Infection Control Outreach Network (DICON) between May 15, 2019, and July 3, 2019. Results: We received 51 responses (response rate, 100%). Most hospital laboratories were located in North Carolina (n = 25, 49%) and Georgia (n = 18, 35%); 28 laboratories (55%) incorporated RUCs. Surveyed laboratories accepted urine samples from any source and various collection methods (eg, indwelling catheter specimens, clean catch specimens). Moreover, 24 laboratories (86%) offered RUCs for all patients, whereas 4 laboratories (14%) restricted RUCs to specific populations (ie, outpatient, emergency room or children). We observed wide variability in the urinalysis criteria used for RUCs (Table 1); 26 unique approaches were used among 28 laboratories. Also, 24 laboratories (86%) used multiple criteria and 4 (14%) used 1 criterion. Of those that used multiple criteria, all 24 proceeded to RUC if at least 1 UA criterion was met. Furthermore, 22 laboratories (79%) incorporated the presence of nitrites as a urinalysis criterion; 21 laboratories (75%) incorporated white blood cell count (WBC) as a criterion. The most frequent WBC cutoffs were “≥5” (n = 11, 39%) and “≥10” (n = 7, 25%). In addition, 21 laboratories (75%) incorporated leukocyte esterase as a urinalysis criterion, with criteria including “positive” (n = 15, 54%), “trace” (n = 4, 14%), “moderate” (n = 1, 4%), and “large” (n = 1, 4%). Also, 17 (61%) laboratories incorporated magnitude of bacteriuria as a urinalysis criterion. The cutoff ranged from “few” (n = 8, 29%), “moderate” (n = 7, 25%), to “many” (n = 2, 7%). Another 3 (11%) laboratories incorporated other criteria: presence of blood (n = 2, 7%) and presence of fungal elements (n = 1, 4%). Only 3 (11%) laboratories utilized epithelial cells as an exclusion criterion where urinalysis would not proceed to culture if epithelial cells in urinalysis samples exceeded the designated limit, ranging from “>5” to “>15”. Conclusions: More than half of the hospitals in our community hospital network utilize RUCs, but criteria varied widely. Future epidemiological research should aim to identify ideal urinalysis parameters as well as specific patient populations that safely benefit from RUC strategies.Funding: NoneDisclosures: None

In this review article, we discuss the epidemiology, microbiology, diagnosis, treatment and prevention of infections associated with cerebrospinal fluid shunts, cerebrospinal fluid drains, and deep brain stimulators. We also briefly discuss prevention strategies with appropriate antibiotics, devices, and operating room practices to decrease the risk of these infections.

Here we summarize an April 2016, 7-patient cluster of human adenovirus (HAdV) infections in a cardiothoracic surgery intensive care unit. We show that the patients were infected with a single HAdV21b type. Rapid HAdV typing diagnostics and effective antiviral interventions are needed for immunocompromised patients suffering from HAdV infections.

Background Continuous infusion cefazolin (CI) has been investigated as a means to optimize antibiotic exposure for prophylaxis against SSI, notably in patients undergoing cardiac procedures involving cardiac bypass (CPB). However, data are limited on its impact on late SSIs and adverse events. In 6/16, the Duke University Hospital (DUH) Antimicrobial Stewardship Team implemented a program to promote CI. We compared the incidence of culture-confirmed SSIs through postoperative day 90 (POD90) between patients receiving either intermittent infusion cefazolin (INT) or CI intraoperatively. We also compared the rate of acute kidney injury (AKI) between groups. Methods This retrospective quasi-experimental design included adult and pediatric patients undergoing cardiac surgery at DUH between March 2014 and August 2018 and receiving intraoperative cefazolin (alone or in combination with other antibiotics). Patients were categorized as CI (having received at least 1 intraoperative CI infusion) or INT. Culture-confirmed SSIs utilizing NHSN definitions were recorded and a relative risk (RR) determined. AKI was defined as a ≥0.3 mg/dL rise in serum creatinine within 2 days postoperatively. Results A total of 2,172 unique surgical procedures (from 2,143 unique patients) were included. Comparisons of groups are summarized in Table 1. Rates of SSIs were 1.1% and 1.6% in the CI and INT groups, respectively (RR [95% confidence interval] for CI 0.73, [0.35, 1.52]). AKI was reported in 12.9% and 17.4% of patients, respectively. Conclusion We were unable to detect a difference in late SSIs between intraoperative CI and INT cefazolin. Differences observed between AKI between groups requires further investigation, but likely impacted by confounders, including pre-existing renal dysfunction. Disclosures All authors: No reported disclosures.

Background Healthcare-associated infections (HAI) remain the leading cause of morbidity and mortality among hospitalized children. Within community hospitals with targeted infection prevention efforts, participation in an infection control network has led to significant decreases in device or procedure-related infections among adult patients. The impact of these interventions has not been assessed in pediatric patients admitted to community hospitals. Methods We conducted a retrospective cohort study to describe the burden of HAI among hospitalized infants (< 1 year old) within 53 community hospitals participating in the Duke Infection Control Outreach Network (DICON) from 2013–2018. We determined the frequency of device-related HAI, central line-associated bloodstream infections (CLABSI), catheter-associated urinary tract infections (CAUTI) and hospital-associated pneumonia or ventilator-associated events (HAP/VAE) using National Healthcare Safety Network (NHSN) definitions; and the burden of HAIs among neonatal intensive care units (NICU) and non-NICU centers. The trend of HAI was analyzed with Spearman’s correlation. Results Thirty hospitals reported 150 HAI among 141 infants over the 6-year period. Median (IQR) time to infection was 10 (4, 20) days after admission. Hospitals with a NICU (15) reported more HAI (median 5, (IQR: 3, 12)) than hospitals without a NICU (median 2 (IQR: 1, 2)) (P = 0.031). CLABSI represented 35% of HAI, HAP/VAE were 23% and CAUTI were 12%. The most frequently isolated primary organism for all HAI was Escherichia coli (22 HAI, 15%) which was also isolated in 39% of CAUTI. Methicillin-resistant and methicillin-susceptible Staphylococcus aureus (S. aureus) were the most commonly isolated organisms among CLABSI (17%) and HAP/VAE (33%). Nine centers with ≥4 years of NICU and Central line (CL) use data reported a median (IQR) rate of 1.2 (0, 2.4) CLABSIs/1,000 central line days. There was no change in median CLABSI rate over time (P = 0.47), Figure 1. Conclusion CLABSI, most commonly caused by S. aureus, represented the majority of HAI reported from hospitalized infants within community hospitals participating in an infection control network. Further research into device utilization practices may inform future interventions to reduce HAI. Disclosures All authors: No reported disclosures.

OBJECTIVETo evaluate seasonal variation in the rate of surgical site infections (SSI) following commonly performed surgical procedures.DESIGNRetrospective cohort study.METHODSWe analyzed 6 years (January 1, 2007, through December 31, 2012) of data from the 15 most commonly performed procedures in 20 hospitals in the Duke Infection Control Outreach Network. We defined summer as July through September. First, we performed 3 separate Poisson regression analyses (unadjusted, multivariable, and polynomial) to estimate prevalence rates and prevalence rate ratios of SSI following procedures performed in summer versus nonsummer months. Then, we stratified our results to obtain estimates based on procedure type and organism type. Finally, we performed a sensitivity analysis to test the robustness of our findings.RESULTSWe identified 4,543 SSI following 441,428 surgical procedures (overall prevalence rate, 1.03/100 procedures). The rate of SSI was significantly higher during the summer compared with the remainder of the year (1.11/100 procedures vs 1.00/100 procedures; prevalence rate ratio, 1.11 [95% CI, 1.04–1.19];P=.002). Stratum-specific SSI calculations revealed higher SSI rates during the summer for both spinal (P=.03) and nonspinal (P=.004) procedures and revealed higher rates during the summer for SSI due to either gram-positive cocci (P=.006) or gram-negative bacilli (P=.004). Multivariable regression analysis and sensitivity analyses confirmed our findings.CONCLUSIONSThe rate of SSI following commonly performed surgical procedures was higher during the summer compared with the remainder of the year. Summer SSI rates remained elevated after stratification by organism and spinal versus nonspinal surgery, and rates did not change after controlling for other known SSI risk factors.Infect. Control Hosp. Epidemiol.2015;36(9):1011–1016

OBJECTIVEHospitals in the National Healthcare Safety Network began reporting laboratory-identified (LabID) Clostridium difficile infection (CDI) events in January 2013. Our study quantified the differences between the LabID and traditional surveillance methods.DESIGNCohort study.SETTINGA cohort of 29 community hospitals in the southeastern United States.METHODSA period of 6 months (January 1, 2013, to June 30, 2013) of prospectively collected data using both LabID and traditional surveillance definitions were analyzed. CDI events with mismatched surveillance categories between LabID and traditional definitions were identified and characterized further. Hospital-onset CDI (HO-CDI) rates for the entire cohort of hospitals were calculated using each method, then hospital-specific HO-CDI rates and standardized infection ratios (SIRs) were calculated. Hospital rankings based on each CDI surveillance measure were compared.RESULTSA total of 1,252 incident LabID CDI events were identified during 708,551 patient-days; 286 (23%) mismatched CDI events were detected. The overall HO-CDI rate was 6.0 vs 4.4 per 10,000 patient-days for LabID and traditional surveillance, respectively (PCONCLUSIONSLabID surveillance resulted in a higher hospital-onset CDI incidence rate than did traditional surveillance. Hospital-specific rankings varied based on the HO-CDI surveillance measure used. A clear understanding of differences in CDI surveillance measures is important when interpreting national and local CDI data.Infect Control Hosp Epidemiol 2014;00(0): 1–7

Objective.Describe the epidemiology of healthcare-related (ie, healthcare-associated and hospital-acquired) pneumonia due to methicillin-resistant Staphylococcus aureus (MRSA) among hospitalized patients in community hospitals.Design.Retrospective cohort study.Setting.Twenty-four community hospitals in the southeastern United States affiliated with the Duke Infection Control Outreach Network (median size, 211 beds; range, 103–658 beds).Methods.Adult patients with healthcare-related MRSA pneumonia admitted to study hospitals from January 1, 2008, to December 31, 2012, were identified using surveillance data. Seasonal and annual incidence rates (cases per 100,000 patient-days) were estimated using generalized estimating equation models. Characteristics of community-onset and hospital-onset cases were compared.Results.A total of 1,048 cases of healthcare-related pneumonia due to MRSA were observed during 5,863,941 patient-days. The annual incidence rate of healthcare-related MRSA pneumonia increased from 11.3 cases per 100,000 patient-days (95% confidence interval [CI], 6.8–18.7) in 2008 to 15.5 cases per 100,000 patient-days (95% CI, 8.4–28.5) in 2012 (P = .055). The incidence rate was highest in winter months and lowest in summer months (15.4 vs 11.1 cases per 100,000 patient-days; incidence rate ratio, 1.39 [95% CI, 1.06–1.82]; P = .016). A total of 814 cases (77.7%) were community-onset healthcare-associated pneumonia cases; only 49 cases (4.7%) were ventilator-associated cases. Of 811 patients whose disposition was known, 240 (29.6%) died during hospitalization or were discharged to hospice.Conclusions.From 2008 through 2012, the incidence of healthcare-related MRSA pneumonia among patients who were admitted to a large network of community hospitals increased, despite the decreasing incidence of invasive MRSA infections nationwide. Additional study is warranted to evaluate trends in this important and potentially modifiable public health problem.Infect Control Hosp Epidemiol 2014;35(12):1452–1457

Background We recently investigated a clonal outbreak of Mycobacterium abscessus molecularly linked to a colonized water supply at a new hospital addition. Use of sterile water instead of tap water for patient care in ICUs successfully mitigated the respiratory phase of the outbreak. We hypothesized that avoidance of tap water would also be associated with decreased respiratory isolation of other nontuberculous mycobacteria (NTM). Methods We analyzed all positive cultures for NTM obtained at our hospital from August 2013 through December 2015. The pre-intervention outbreak period was defined as August 2013 through May 2014; the tap water avoidance intervention period was defined as June 2014 through December 2015. NTM isolation was defined as a positive culture from a respiratory specimen obtained from an ICU patient on day 3 or later of hospitalization. We also performed AFB cultures of biofilms obtained from ICU water sources. Results NTM were isolated from 137 patients during 70,168 patient-days (figure). NTM isolation decreased from 41.0 patients/10,000 patient-days in the outbreak period to 9.9 patients/10,000 patient-days in the intervention period (IRR, 0.24; 95% CI, 0.17–0.34; P < .0001) (table). Incidence rates of the 4 most common NTM (M. abscessus, M. chelonae/immunogenum, M. avium complex, and M. gordonae) also markedly decreased. Biofilm cultures were positive for at least 1 NTM isolate in 25 of 33 (76%) ICU water sources, including M. abscessus (n = 11, 33%), M. chelonae/immunogenum (n = 11, 33%), and M. gordonae (n = 11, 33%). Conclusion The use of sterile water for ICU patient care substantially decreased NTM isolation from patient respiratory specimens, presumably reducing risk of symptomatic infection. Hospitals with endemic NTM should consider tap water avoidance for high-risk patients. Disclosures All authors: No reported disclosures.

Background We investigated an increase in hospital-acquired invasive fungal infections (HA-IFI) among patients admitted to adjacent hematopoietic stem cell transplant (HSCT) and hematologic malignancy (HM) wards in the setting of a large construction project adjacent to the hospital. Methods We defined cases of HA-IFI as HSCT or HM patients who met criteria for probable or proven IFI with suspected inpatient acquisition. We hypothesized that outside construction increased internal particle/spore counts despite preconstruction prevention efforts. The environmental investigation included an evaluation of storage/distribution of supplies, air handler inspections, air particulate counts, and bioaerosol sampling of airborne fungal spores. Results From October 2017 to January 2018, 11 cases of probable/proven HA-IFI occurred (Figure 1). Infections caused by multiple pathogens (Figure 2) ranged from pneumonia and sinusitis to disseminated disease. Bioaerosol sampling and particulate counts were taken from unit corridors and rooms on both wards. Fungal species identified via bioaerosol sampling were primarily Penicillium and Cladosporium species, with rare Aspergillus identified. Geometric mean particulate counts of 1 μm aerodynamic size were reduced by 88% and 75% on the HM and HSCT wards, respectively (Figure 3). Interventions on these units occurred from January to February 2018 and included: limiting the frequency of outdoor air exchanges on air handler units, reinforcing seals around entrance doors, adjusting room pressurizations to be positive or neutral on HM ward (HSCT ward is already a positive pressure environment), eliminating cardboard associated with supplies, and requiring N95 respirators for HSCT patients when off unit. After implementing these environmental control measures, we have not identified additional cases of HA-IFI on these wards. Conclusion We describe a multispecies outbreak of IFI in HM and HSCT patients potentially associated with new building construction that occurred despite implementation of multiple pre-construction control efforts. A multifaceted strategy to improve air quality and protect patients on and off high-risk units was needed to mitigate the outbreak. Disclosures All authors: No reported disclosures.

Background We performed an investigation after noting an increase in hospital-onset (HO) KPC-producing Enterobacteriaceae (KPC-E) infections in patients admitted to a tertiary referral hospital in North Carolina. Methods We defined pre-outbreak (January 1, 2017–June 30, 2017), outbreak (July 1, 2017–October 31, 2017), and post-outbreak (November 1, 2017–March 31, 2018) phases. A clinical case was defined as any positive clinical culture for KPC-E. HO was defined as a positive clinical or surveillance culture collected on hospital day ≥3. Patients were mapped in space and time to inform targeted environmental sampling. Whole-genome sequencing (WGS) was performed on selected KPC K. pneumoniae environmental and patient isolates to determine relatedness. In October 2017, a CRE prevention bundle was implemented that included daily communication of CRE patient movement, increased audits/feedback of HCW compliance with hand hygiene, enhanced cleaning and disinfection in CRE rooms and high-risk units with bleach and UVC disinfection, and weekly rectal surveillance screens in four adult ICUs. Results 0.67 clinical cases of KPC-E per month were observed during the pre-outbreak period compared with 3.75 clinical cases of KPC-E per month during the outbreak period. K. pneumoniae was the most common species (Figure 1). Mapping of patients revealed probable direct and indirect transmission between patients in multiple hospital units (Figure 2). three patients who were non-sequentially admitted to the same ICU room over a 12-week span acquired KPC K. pneumoniae (Figure 2). Environmental cultures from the in-room sink drain and P-trap grew KPC K. pneumoniae that was related to the patient isolates by WGS; the sink was removed. Although no additional clinical cases of KPC-E occurred after full implementation of the bundle and sink removal, we continued to observe acquisition of KPC-E rectal colonization in all four ICUs (Figure 3). Conclusion We describe a multispecies outbreak of KPC-E that was mitigated through evidence-based CRE control measures and removal of a colonized sink. However, ongoing low-level presumed transmission of KPC points to persistent environmental sources. Additional study is needed to understand the prevalence of CRE in hospital sinks, factors that drive drain colonization, and contribution of CRE in a sink to nosocomial transmission. Disclosures All authors: No reported disclosures.

This cohort study examines the 5-year incidence of community-acquired and health care facility–associated Clostridioides difficile infection among patients in US community hospitals., Key Points Question What are the current trends in incidence rates of community-acquired and health care facility–associated Clostridioides difficile in US community hospitals? Findings In this multicenter cohort study of 2 025 678 admissions and 21 254 cases of Clostridioides difficile infection, the incidence of health care facility–associated C difficile infection decreased from 2013 to 2017, whereas the incidence of community-acquired C difficile infection during the same period showed no statistically significant change. The proportion of cases classified as community acquired increased over time. Meaning The findings suggest that the proportion of community-acquired C difficile infections is increasing over time and warrants further study to identify the factors behind this trend., Importance Clostridioides difficile infection (CDI) remains a leading cause of health care facility–associated infection. A greater understanding of the regional epidemiologic profile of CDI could inform targeted prevention strategies. Objectives To assess trends in incidence of health care facility–associated and community-acquired CDI among hospitalized patients over time and to conduct a subanalysis of trends in the NAP1 strain of CDI over time. Design, Setting, and Participants This long-term multicenter cohort study reviewed records of patients (N = 2 025 678) admitted to a network of 43 regional community hospitals primarily in the southeastern United States from January 1, 2013, through December 31, 2017. Generalized linear mixed-effects models were used to adjust for potential clustering within facilities and changing test method (nucleic acid amplification testing or toxin enzyme immunoassay) over time. Main Outcomes and Measures Clostridioides difficile infection incidence rates were counted as cases per 1000 admissions for community-acquired and total CDI cases or cases per 10 000 patient-days for health care facility–associated CDI. Long-term trends in the proportion of cases acquired in the community and in NAP1 strain incidence were also evaluated. Results A total of 2 025 678 admissions and 21 254 CDI cases were included (12 678 [59.6%] female; median [interquartile range] age, 69 [55-80] years). Median (interquartile range) total CDI incidence increased slightly from 7.9 (3.5-12.4) cases per 1000 admissions in 2013 to 9.3 (4.9-13.7) cases per 1000 admissions in 2017. After adjustment, the overall incidence of health care facility–associated CDI declined (incidence rate ratio [IRR], 0.995; 95% CI, 0.990-0.999; P = .03), whereas insufficient evidence was found for either an increase or a decrease in community-acquired CDI (IRR, 1.004; 95% CI, 0.999-1.009; P = .14). The proportion of cases classified as community acquired increased over time from a mean (SD) of 0.49 (0.28) in 2013 to 0.61 (0.26) in 2017 (odds ratio, 1.010 per month; 95% CI, 1.006-1.015; P

Background We evaluated the role of an in-room sink in NDM-1 K. pneumoniae (NDMKP) transmission. Methods In October 2017, Infection Prevention (IP) initiated weekly point prevalence rectal screening cultures in 4 ICUs. In 3/2018, IP launched an epidemiologic and environmental investigation following identification of a patient with NDMKP rectal colonization. Environmental samples including swabs of biofilm from drains and water from p-traps were obtained from the in-room sink. Illumina whole-genome sequencing (WGS) was performed on all NDMKP patient and environmental isolates. Single nucleotide variants (SNVs) were identified against the reference Klebsiella pneumoniae strain MLST15 (NZ_CP022127), and isolates within 150 SNVs of each other were considered to be genomically related. Results Two patients were identified with NDMKP infection or colonization between July 2017 and March 2018. The index patient had prolonged hospitalization and developed NDMKP bacteremia on hospital day (HD) 30. Approximately 9 months later, the second patient was admitted to the same ICU room that had been occupied by the index patient for 13 days and was identified to have NDMKP rectal colonization on HD 5. Environmental samples from the in-room sink of the ICU room grew NDMKP. WGS demonstrated relatedness between NDMKP isolates from the 2 patients (112 SNV), the index patient and the sink (52 SNV), and the second patient and the sink (80 SNV). The in-room sink was replaced in 4/18 and no further cases of NDMKP infection or colonization have been identified at DUH in over 12 months. Conclusion We report an NDM-1 K. pneumoniae transmission event possibly related to a contaminated in-room sink drain. Remarkably, 9 months elapsed between the index case and the second case, with no additional interim cases detected on weekly point-prevalence screening or clinical cultures. The long duration of time between and the index patient, secondary case, and sink culture may explain why WGS showed relatedness but not identical clones. Education around sink use, design, and more effective cleaning strategies are needed to mitigate environment-to-patient transmission of CRO. Disclosures All authors: No reported disclosures.

Clostridium difficile is a major cause of infection worldwide and is associated with increasing morbidity and mortality in vulnerable patient populations. Metronidazole and oral vancomycin are the currently recommended therapies for the treatment of C. difficile infection (CDI) but are associated with unacceptably high rates of disease recurrence. Novel therapies for the treatment of CDI and prevention of recurrent CDI are urgently needed. Important developments in the treatment of CDI are currently underway and include: novel antibacterial agents with narrower antimicrobial spectra of activity, manipulation of the gut microbiota and enhancement of the host antibody immune response.

OBJECTIVETo determine whether antimicrobial-impregnated textiles decrease the acquisition of pathogens by healthcare provider (HCP) clothing.DESIGNWe completed a 3-arm randomized controlled trial to test the efficacy of 2 types of antimicrobial-impregnated clothing compared to standard HCP clothing. Cultures were obtained from each nurse participant, the healthcare environment, and patients during each shift. The primary outcome was the change in total contamination on nurse scrubs, measured as the sum of colony-forming units (CFU) of bacteria.PARTICIPANTS AND SETTINGNurses working in medical and surgical ICUs in a 936-bed tertiary-care hospital.INTERVENTIONNurse subjects wore standard cotton-polyester surgical scrubs (control), scrubs that contained a complex element compound with a silver-alloy embedded in its fibers (Scrub 1), or scrubs impregnated with an organosilane-based quaternary ammonium and a hydrophobic fluoroacrylate copolymer emulsion (Scrub 2). Nurse participants were blinded to scrub type and randomly participated in all 3 arms during 3 consecutive 12-hour shifts in the intensive care unit.RESULTSIn total, 40 nurses were enrolled and completed 3 shifts. Analyses of 2,919 cultures from the environment and 2,185 from HCP clothing showed that scrub type was not associated with a change in HCP clothing contamination (P=.70). Mean difference estimates were 0.118 for the Scrub 1 arm (95% confidence interval [CI], −0.206 to 0.441; P=.48) and 0.009 for the Scrub 2 rm (95% CI, −0.323 to 0.342; P=.96) compared to the control. HCP became newly contaminated with important pathogens during 19 of the 120 shifts (16%).CONCLUSIONSAntimicrobial-impregnated scrubs were not effective at reducing HCP contamination. However, the environment is an important source of HCP clothing contamination.TRIAL REGISTRATIONClinicaltrials.gov Identifier: NCT 02645214Infect Control Hosp Epidemiol 2017;38:1147–1154

Background The rate of community-acquired Clostridium difficile infection (CA-CDI) is increasing. While receipt of antibiotics remains an important risk factor for CDI, studies related to acquisition of C. difficile outside of hospitals are lacking. As a result, risk factors for exposure to C. difficile in community settings have been inadequately studied. Main objective To identify novel environmental risk factors for CA-CDI Methods We performed a population-based retrospective cohort study of patients with CA-CDI from 1/1/2007 through 12/31/2014 in a 10-county area in central North Carolina. 360 Census Tracts in these 10 counties were used as the demographic Geographic Information System (GIS) base-map. Longitude and latitude (X, Y) coordinates were generated from patient home addresses and overlaid to Census Tracts polygons using ArcGIS; ArcView was used to assess “hot-spots” or clusters of CA-CDI. We then constructed a mixed hierarchical model to identify environmental variables independently associated with increased rates of CA-CDI. Results A total of 1,895 unique patients met our criteria for CA-CDI. The mean patient age was 54.5 years; 62% were female and 70% were Caucasian. 402 (21%) patient addresses were located in “hot spots” or clusters of CA-CDI (p

OBJECTIVETo evaluate the impact of multidrug-resistant gram-negative rod (MDR-GNR) infections on mortality and healthcare resource utilization in community hospitals.DESIGNTwo matched case-control analyses.SETTINGSix community hospitals participating in the Duke Infection Control Outreach Network from January 1, 2010, through December 31, 2012.PARTICIPANTSAdult patients admitted to study hospitals during the study period.METHODSPatients with MDR-GNR bloodstream and urinary tract infections were compared with 2 groups: (1) patients with infections due to nonMDR-GNR and (2) control patients representative of the nonpsychiatric, non-obstetric hospitalized population. Four outcomes were assessed: mortality, direct cost of hospitalization, length of stay, and 30-day readmission rates. Multivariable regression models were created to estimate the effect of MDR status on each outcome measure.RESULTSNo mortality difference was seen in either analysis. Patients with MDR-GNR infections had 2.03 higher odds of 30-day readmission compared with patients with nonMDR-GNR infections (95% CI, 1.04–3.97, P=.04). There was no difference in hospital direct costs between patients with MDR-GNR infections and patients with nonMDR-GNR infections. Hospitalizations for patients with MDR-GNR infections cost $5,320.03 more (95% CI, $2,366.02–$8,274.05, PPCONCLUSIONSOur study provides novel data regarding the clinical and financial impact of MDR gram-negative bacterial infections in community hospitals. There was no difference in mortality between patients with MDR-GNR infections and patients with nonMDR-GNR infections or control patients.Infect Control Hosp Epidemiol 2016;1–8

Background Nontuberculous mycobacteria (NTM) commonly colonize municipal water supplies and cause healthcare-associated outbreaks. We investigated a biphasic outbreak of Mycobacterium abscessus at a tertiary care hospital. Methods Case patients had recent hospital exposure and laboratory-confirmed colonization or infection with M. abscessus from January 2013 through December 2015. We conducted a multidisciplinary epidemiologic, field, and laboratory investigation. Results The incidence rate of M. abscessus increased from 0.7 cases per 10000 patient-days during the baseline period (January 2013-July 2013) to 3.0 cases per 10000 patient-days during phase 1 of the outbreak (August 2013-May 2014) (incidence rate ratio, 4.6 [95% confidence interval, 2.3-8.8]; P < .001). Thirty-six of 71 (51%) phase 1 cases were lung transplant patients with positive respiratory cultures. We eliminated tap water exposure to the aerodigestive tract among high-risk patients, and the incidence rate decreased to baseline. Twelve of 24 (50%) phase 2 (December 2014-June 2015) cases occurred in cardiac surgery patients with invasive infections. Phase 2 resolved after we implemented an intensified disinfection protocol and used sterile water for heater-cooler units of cardiopulmonary bypass machines. Molecular fingerprinting of clinical isolates identified 2 clonal strains of M. abscessus; 1 clone was isolated from water sources at a new hospital addition. We made several water engineering interventions to improve water flow and increase disinfectant levels. Conclusions We investigated and mitigated a 2-phase clonal outbreak of M. abscessus linked to hospital tap water. Healthcare facilities with endemic NTM should consider similar tap water avoidance and engineering strategies to decrease risk of NTM infection.

Summary Background Patients admitted to hospital can acquire multidrug-resistant organisms and Clostridium difficile from inadequately disinfected environmental surfaces. We determined the effect of three enhanced strategies for terminal room disinfection (disinfection of a room between occupying patients) on acquisition and infection due to meticillin-resistant Staphylococcus aureus , vancomycin-resistant enterococci, C difficile , and multidrug-resistant Acinetobacter . Methods We did a pragmatic, cluster-randomised, crossover trial at nine hospitals in the southeastern USA. Rooms from which a patient with infection or colonisation with a target organism was discharged were terminally disinfected with one of four strategies: reference (quaternary ammonium disinfectant except for C difficile , for which bleach was used); UV (quaternary ammonium disinfectant and disinfecting ultraviolet [UV-C] light except for C difficile , for which bleach and UV-C were used); bleach; and bleach and UV-C. The next patient admitted to the targeted room was considered exposed. Every strategy was used at each hospital in four consecutive 7-month periods. We randomly assigned the sequence of strategies for each hospital (1:1:1:1). The primary outcomes were the incidence of infection or colonisation with all target organisms among exposed patients and the incidence of C difficile infection among exposed patients in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT01579370. Findings 31 226 patients were exposed; 21 395 (69%) met all inclusion criteria, including 4916 in the reference group, 5178 in the UV group, 5438 in the bleach group, and 5863 in the bleach and UV group. 115 patients had the primary outcome during 22 426 exposure days in the reference group (51·3 per 10 000 exposure days). The incidence of target organisms among exposed patients was significantly lower after adding UV to standard cleaning strategies (n=76; 33·9 cases per 10 000 exposure days; relative risk [RR] 0·70, 95% CI 0·50–0·98; p=0·036). The primary outcome was not statistically lower with bleach (n=101; 41·6 cases per 10 000 exposure days; RR 0·85, 95% CI 0·69–1·04; p=0·116), or bleach and UV (n=131; 45·6 cases per 10 000 exposure days; RR 0·91, 95% CI 0·76–1·09; p=0·303) among exposed patients. Similarly, the incidence of C difficile infection among exposed patients was not changed after adding UV to cleaning with bleach (n=38 vs 36; 30·4 cases vs 31·6 cases per 10 000 exposure days; RR 1·0, 95% CI 0·57–1·75; p=0·997). Interpretation A contaminated health-care environment is an important source for acquisition of pathogens; enhanced terminal room disinfection decreases this risk. Funding US Centers for Disease Control and Prevention.

Bacteremia is a common infectious complication in hemodialysis patients. Metastatic sites of infection including infective endocarditis, vertebral osteomyelitis, spinal epidural abscess, and septic arthritis occur relatively frequently. These complications are associated with increased morbidity and mortality in hemodialysis patients. Early clinical recognition and appropriate management of these infections are necessary, and strategies to reduce the occurrence of bacteremia in this patient population are warranted.

Background Per National Healthcare Safety Network (NHSN) rules, when multiple procedures are performed during a single operation, the operation is counted in the surgical site infection (SSI) denominator of each NHSN surgical procedure category. SSIs, however, are counted only in the highest-ranking procedure category. These rules result in procedures that are ineligible to have an associated SSI being counted in SSI denominators. Methods We analyzed 3 years (January 1, 2015–December 31, 2017) of laminectomy and rectal surgery SSI data from hospitals in the Duke Infection Control Outreach Network (DICON) that used ICD procedure codes to assign denominators per NHSN definitions. We compared SSI rates using two different denominators: NHSN denominators vs. reduced denominators that counted only primary laminectomy and rectal surgery procedures. We calculated rate ratios (RR) to compare the NHSN and adjusted SSI rates for each procedure for all hospitals that reported at least 1 SSI. Results Eleven hospitals reported 87 infections following 17,247 laminectomy procedures. The overall SSI rate increased by 44% when only primary procedures were counted in the denominator (RR 1.44); but individual hospital RR ranged from 1.10 to 2.20 (Table 1). 5 hospitals reported seven SSIs following 740 rectal procedures. The overall SSI rate increased by 143% when only primary procedures were counted in the denominator (RR 2.43), but individual hospital RR ranged from 2.00 to 5.00 (Table 1). Conclusion NHSN’s method for calculating SSI denominators underestimates true SSI rate. The current method particularly impacts procedures that are frequently performed in conjunction with higher-ranking NHSN procedures. Counting only primary procedures in procedure category denominators would provide higher, more accurate SSI rates. Table 1. Comparison of SSI Rates Calculated Using Adjusted Denominators vs. NHSN Denominators Laminectomy Procedures Hospital Adjusted Rate NHSN Rate RR 1 0.55 0.50 1.10 2 0.61 0.53 1.15 3 0.63 0.55 1.16 4 0.26 0.22 1.22 5 1.18 0.90 1.30 6 1.43 1.06 1.34 7 0.24 0.18 1.34 8 0.99 0.70 1.41 9 0.82 0.46 1.77 10 0.84 0.41 2.05 11 1.09 0.50 2.20 Overall 0.72 0.50 1.44 Rectal Surgeries Hospital Adjusted Rate NHSN Rate RR 1 9.52 4.77 2.00 2 0.60 0.27 2.27 3 2.53 1.07 2.37 4 2.70 0.81 3.35 5 5.00 1.00 5.00 Overall 2.30 0.95 2.43 Disclosures All authors: No reported disclosures.

OBJECTIVETo describe the epidemiology of complex surgical site infection (SSI) following commonly performed surgical procedures in community hospitals and to characterize trends of SSI prevalence rates over time for MRSA and other common pathogensMETHODSWe prospectively collected SSI data at 29 community hospitals in the southeastern United States from 2008 through 2012. We determined the overall prevalence rates of SSI for commonly performed procedures during this 5-year study period. For each year of the study, we then calculated prevalence rates of SSI stratified by causative organism. We created log-binomial regression models to analyze trends of SSI prevalence over time for all pathogens combined and specifically for MRSA.RESULTSA total of 3,988 complex SSIs occurred following 532,694 procedures (prevalence rate, 0.7 infections per 100 procedures). SSIs occurred most frequently after small bowel surgery, peripheral vascular bypass surgery, and colon surgery. Staphylococcus aureus was the most common pathogen. The prevalence rate of SSI decreased from 0.76 infections per 100 procedures in 2008 to 0.69 infections per 100 procedures in 2012 (prevalence rate ratio [PRR], 0.90; 95% confidence interval [CI], 0.82–1.00). A more substantial decrease in MRSA SSI (PRR, 0.69; 95% CI, 0.54–0.89) was largely responsible for this overall trend.CONCLUSIONSThe prevalence of MRSA SSI decreased from 2008 to 2012 in our network of community hospitals. This decrease in MRSA SSI prevalence led to an overall decrease in SSI prevalence over the study period.Infect Control Hosp Epidemiol 2016;37:519–526

OBJECTIVETo determine whether daily chlorhexidine gluconate (CHG) bathing of intensive care unit (ICU) patients leads to a decrease in hospital-acquired infections (HAIs), particularly infections caused by methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE).DESIGNInterrupted time series analysis.SETTINGThe study included 33 community hospitals participating in the Duke Infection Control Outreach Network from January 2008 through December 2013.PARTICIPANTSAll ICU patients at study hospitals during the study period.METHODSOf the 33 hospitals, 17 hospitals implemented CHG bathing during the study period, and 16 hospitals that did not perform CHG bathing served as controls. Primary pre-specified outcomes included ICU central-line–associated bloodstream infections (CLABSIs), primary bloodstream infections (BSI), ventilator-associated pneumonia (VAP), and catheter-associated urinary tract infections (CAUTIs). MRSA and VRE HAIs were also evaluated.RESULTSChlorhexidine gluconate (CHG) bathing was associated with a significant downward trend in incidence rates of ICU CLABSI (incidence rate ratio [IRR], 0.96; 95% confidence interval [CI], 0.93–0.99), ICU primary BSI (IRR, 0.96; 95% CI, 0.94–0.99), VRE CLABSIs (IRR, 0.97; 95% CI, 0.97–0.98), and all combined VRE infections (IRR, 0.96; 95% CI, 0.93–1.00). No significant trend in MRSA infection incidence rates was identified prior to or following the implementation of CHG bathing.CONCLUSIONSIn this multicenter, real-world analysis of the impact of CHG bathing, hospitals that implemented CHG bathing attained a decrease in ICU CLABSIs, ICU primary BSIs, and VRE CLABSIs. CHG bathing did not affect rates of specific or overall infections due to MRSA. Our findings support daily CHG bathing of ICU patients.Infect Control Hosp Epidemiol 2016;37:791–797

OBJECTIVETo determine the association (1) between shorter operative duration and surgical site infection (SSI) and (2) between surgeon median operative duration and SSI risk among first-time hip and knee arthroplasties.DESIGNRetrospective cohort studySETTINGA total of 43 community hospitals located in the southeastern United States.PATIENTSAdults who developed SSIs according to National Healthcare Safety Network criteria within 365 days of first-time knee or hip arthroplasties performed between January 1, 2008 and December 31, 2012.METHODSLog-binomial regression models estimated the association (1) between operative duration and SSI outcome and (2) between surgeon median operative duration and SSI outcome. Hip and knee arthroplasties were evaluated in separate models. Each model was adjusted for American Society of Anesthesiology score and patient age.RESULTSA total of 25,531 hip arthroplasties and 42,187 knee arthroplasties were included in the study. The risk of SSI in knee arthroplasties with an operative duration shorter than the 25th percentile was 0.40 times the risk of SSI in knee arthroplasties with an operative duration between the 25th and 75th percentile (risk ratio [RR], 0.40; 95% confidence interval [CI], 0.38–0.56; PP=.36). Knee arthroplasty surgeons with shorter median operative durations had a lower risk of SSI than surgeons with typical median operative durations (RR, 0.52; 95% CI, 0.43–0.64; PCONCLUSIONSShort operative durations were not associated with a higher SSI risk for knee or hip arthroplasty procedures in our analysis.Infect. Control Hosp. Epidemiol. 2015;36(12):1431–1436

OBJECT The relationship between time of year and surgical site infection (SSI) following neurosurgical procedures is poorly understood. Authors of previous reports have demonstrated that rates of SSI following neurosurgical procedures performed during the summer months were higher compared with rates during other seasons. It is unclear, however, if this difference was related to climatological changes or inexperienced medical trainees (the July effect). The aim of this study was to evaluate for seasonal variation of SSI following spine surgery in a network of nonteaching community hospitals. METHODS The authors analyzed 6 years of prospectively collected surveillance data (January 1, 2007, to December 31, 2012) from all laminectomies and spinal fusions from 20 hospitals in the Duke Infection Control Outreach Network of community hospitals. Surgical site infections were defined using National Healthcare Safety Network criteria and identified using standardized methods across study hospitals. Regression models were then constructed using Poisson distribution to evaluate for seasonal trends by month. Each analysis was first performed for all SSIs and then for SSIs caused by specific organisms or classes of organisms. Categorical analysis was performed using two separate definitions of summer: June through September (definition 1), and July through September (definition 2). The prevalence rate of SSIs during the summer was compared with the prevalence rate during the remainder of the year by calculating prevalence rate ratios and 95% confidence intervals. RESULTS The authors identified 642 SSIs following 57,559 neurosurgical procedures (overall prevalence rate = 1.11/100 procedures); 215 occurred following 24,466 laminectomies (prevalence rate = 0.88/100 procedures), and 427 following 33,093 spinal fusions (prevalence rate = 1.29/100 procedures). Common causes of SSI were Staphylococcus aureus (n = 380; 59%), coagulase-negative staphylococci (n = 90; 14%), and Escherichia coli (n = 41; 6.4%). Poisson regression models demonstrated increases in the rates of SSI during each of the summer months for all SSIs and SSIs due to gram-positive cocci, S. aureus, and methicillin-sensitive S. aureus. Categorical analysis confirmed that the rate of SSI during the 4-month summer period was higher than the rate during the remainder of the year, regardless of which definition for summer was used (definition 1, p = 0.008; definition 2, p = 0.003). Similarly, the rates of SSI due to grampositive cocci and S. aureus were higher during the summer months than the remainder of the year regardless of which definition of summer was used. However, the rate of SSI due to gram-negative bacilli was not. CONCLUSIONS The rate of SSI following fusion or spinal laminectomy/laminoplasty was higher during the summer in this network of community hospitals. The increase appears to be related to increases in SSIs caused by gram-positive cocci and, more specifically, S. aureus. Given the nonteaching nature of these hospitals, the findings demonstrate that increases in the rate of SSI during the summer are more likely related to ecological and/or environmental factors than the July effect.

Background The NHSN recently updated risk adjustment models and “rebaselined” Standardized Infection Ratios (SIRs) for healthcare-associated infections. The CDC expected that hospital SIRs would generally increase. However, the impact of rebaselining on individual hospitals’ SIRs was unknown. Accordingly, we assessed the impact of rebaselining on SIRs in a network of community hospitals. Methods We analyzed 2016 SIR data for CAUTI, MRSA LabID events, CDI LabID events, colon SSIs (COLO), and abdominal hysterectomy SSIs (HYST) from 38 hospitals in the Duke Infection Control Outreach Network (DICON). SIRs calculated using the old and new baselines were compared. Wilcoxon signed rank test was performed to determine whether hospitals’ SIRs changed significantly following rebaselining. Hospitals were ranked by SIR for each metric, and change in rank following rebaselining was determined. Meaningful change in rank was defined as increase or decrease by ≥4 places (greater than a decile). Hospitals that did not have an SIR calculated for a given metric were excluded from that metric’s analysis. Results Median hospital SIRs for CAUTI and CDI increased significantly after rebaselining (0.587 vs 0.307, P Conclusion SIRs increased following rebaselining for CAUTI and CDI but did not change significantly for MRSA, COLO, or HYST. The majority of hospitals’ SIR rank did not change meaningfully following rebaselining. Disclosures D. Sexton, Centers for Disease Control and Prevention: Grant Investigator, Grant recipient; Centers for Disease Control and Prevention Foundation: Grant Investigator, Grant recipient; UpToDate: Collaborator, Royalty Recipient

Background We recently mitigated a clonal outbreak of Mycobacterium abscessus, including a large cluster of patients who developed invasive infection after exposure to heater-cooler units (HCU) during cardiac surgery. Recent studies have described a small number of Mycobacterium chimera infections linked to open-heart surgery; however, little is known about the epidemiology and clinical courses of cardiac surgery patients with invasive infection from rapidly-growing mycobacteria, such as M. abscessus. Methods We retrospectively collected clinical data from all patients who underwent cardiac surgery at our hospital and had positive cultures for M. abscessus from 2013 to 2016. We excluded heart transplant recipients and patients who at time of diagnosis had ventricular assist devices. We analyzed patient characteristics, antibiotic treatment courses, surgical interventions, and clinical outcomes. Results Nine cardiac surgery patients who met the case definition developed culture-proven invasive infection from M. abscessus (Figure 1). Seven (78%) infections occurred after surgeries that included valve replacement. Median time from suspected inoculation in the operating room to first positive culture was 49 days (interquartile range, 38–115 days). Seven (78%) patients had bloodstream infections, and six (67%) patients had sternal wound infections. Six (67%) patients developed disseminated disease with infection at multiple sites. All patients received combination antimicrobial therapy. The most common majority regimen (n = 6) was imipenem, amikacin, and tigecycline. Four (44%) patients experienced therapy-limiting antibiotic toxicities (Figure 2). Seven (78%) patients were well enough to undergo at least one surgical debridement. Five (56%) patients stopped therapy due to presumed cure, but four (44%) patients had deaths attributable to M. abscessus infection. Conclusion Invasive M. abscessus infection after cardiac surgery was associated with high morbidity and mortality. Most patients underwent surgical debridement and received prolonged three-drug antimicrobial therapy, which was complicated by numerous antibiotic toxicities. Treatment cured five patients, but four patients died from mycobacterial disease. Disclosures All authors: No reported disclosures.

Background ECMO recipients who develop bloodstream infections (BSI) meeting CLABSI criteria are publically-reported in inter-facility comparisons and contribute to potential penalties from CMS. We aimed to determine the incidence of BSI, specifically CLABSI, following receipt of ECMO at one of the largest ECMO centers in the US. Methods Adults who received ECMO at Duke University Hospital from 1/1/2014–12/31/2016 were included in the study. Cases were patients who acquired BSI during the ECMO exposure period, defined as 2 days after cannulation through 7 days after decannulation. Electronic medical records of case patients were reviewed and data were abstracted using a standardized template. To calculate CLABSI incidence rates (IR), we assumed that all patients on ECMO had 1 or more central venous catheters (CVC) for the duration of ECMO. Results 426 patients received 3532 days of ECMO during the 3-year study period. 29 (6.8%) patients acquired BSI (IR 8.2 /1000 ECMO days (ED)) after a median ECMO duration of 7 (range 2, 39) days. Of these, 13 met criteria for primary CLABSI (IR 3.7/1000 ED), whereas 9 had a single blood culture (BC) positive for a common commensal organism and 7 had BSI secondary to pneumonia. Although ECMO patients only represented 8% of CVC days during the study period, they accounted for 22% of reported CLABSIs for the medical (MICU) and cardiothoracic surgical ICUs (CTICU). 10 (77%) CLABSI patients had femoral sites of ECMO cannulation and/or CVC insertion and 12 (92%) were receiving broad-spectrum antibiotics at the time of CLABSI. Patients with CLABSI and secondary BSI predominantly had infections due to gram-negative rods (Fig 1). The organism recovered from the BC was susceptible to the antibiotics received in 14 (48%) of patients with positive BC. Conclusion The rate of CLABSI was more than 3 times higher in our cohort of ECMO recipients than nationally reported rates for academic MICUs and CTICUs. Research is needed to understand the preventability of these infections, as traditional prevention measures such as avoidance of the femoral site and prophylactic ABX may not be applicable or effective in this high-risk population. Furthermore, NHSN should update its CLABSI definition and/or risk adjustment to account for hospitals with high ECMO utilization. Disclosures M. Daneshmand, Maquet: Grant Investigator, Grant recipient; D. Sexton, Centers for Disease Control and Prevention: Grant Investigator, Grant recipient; Centers for Disease Control and Prevention Foundation: Grant Investigator, Grant recipient; UpToDate: Collaborator, Royalty Recipient

As with surgical procedures, regular surveillance of infectious complications following cardiac implantable electronic device procedures is possible with electronic means combining queries of ICD-9 codes and microbiologic data. Feedback of complication rates may lead to improved patient outcomes., Background. The optimum approach for infectious complication surveillance for cardiac implantable electronic device (CIED) procedures is unclear. We created an automated surveillance tool for infectious complications after CIED procedures. Methods. Adults having CIED procedures between January 1, 2005 and December 31, 2011 at Duke University Hospital were identified retrospectively using International Classification of Diseases, 9th revision (ICD-9) procedure codes. Potential infections were identified with combinations of ICD-9 diagnosis codes and microbiology data for 365 days postprocedure. All microbiology-identified and a subset of ICD-9 code-identified possible cases, as well as a subset of procedures without microbiology or ICD-9 codes, were reviewed. Test performance characteristics for specific queries were calculated. Results. Overall, 6097 patients had 7137 procedures. Of these, 1686 procedures with potential infectious complications were identified: 174 by both ICD-9 code and microbiology, 14 only by microbiology, and 1498 only by ICD-9 criteria. We reviewed 558 potential cases, including all 188 microbiology-identified cases, 250 randomly selected ICD-9 cases, and 120 with neither. Overall, 65 unique infections were identified, including 5 of 250 reviewed cases identified only by ICD-9 codes. Queries that included microbiology data and ICD-9 code 996.61 had good overall test performance, with sensitivities of approximately 90% and specificities of approximately 80%. Queries with ICD-9 codes alone had poor specificity. Extrapolation of reviewed infectious rates to nonreviewed cases yields an estimated rate of infection of 1.3%. Conclusions. Electronic queries with combinations of ICD-9 codes and microbiologic data can be created and have good test performance characteristics for identifying likely infectious complications of CIED procedures.