Prevention of Clostridioides difficile infection (CDI) is a national priority and may be facilitated by deployment of the Targeted Assessment for Prevention (TAP) Strategy, a quality improvement framework providing a focused approach to infection prevention. This article describes the process and outcomes of TAP Strategy implementation for CDI prevention in a healthcare system.

Hospital A was identified based on CDI surveillance data indicating an excess burden of infections above the national goal; hospitals B and C participated as part of systemwide deployment. TAP facility assessments were administered to staff to identify infection control gaps and inform CDI prevention interventions. Retrospective analysis was performed using negative-binomial, interrupted time series (ITS) regression to assess overall effect of targeted CDI prevention efforts. Analysis included hospital-onset, laboratory-identified C. difficile event data for 18 months before and after implementation of the TAP facility assessments.

The systemwide monthly CDI rate significantly decreased at the intervention (β2, −44%; P = .017), and the postintervention CDI rate trend showed a sustained decrease (β1 + β3; −12% per month; P = .008). At an individual hospital level, the CDI rate trend significantly decreased in the postintervention period at hospital A only (β1 + β3, −26% per month; P = .003).

This project demonstrates TAP Strategy implementation in a healthcare system, yielding significant decrease in the laboratory-identified C. difficile rate trend in the postintervention period at the system level and in hospital A. This project highlights the potential benefit of directing prevention efforts to facilities with the highest burden of excess infections to more efficiently reduce CDI rates.

To test the hypothesis that long-term care facility (LTCF) residents with Clostridium difficile infection (CDI) or asymptomatic carriage of toxigenic strains are an important source of transmission in the LTCF and in the hospital during acute-care admissions.

A 6-month cohort study with identification of transmission events was conducted based on tracking of patient movement combined with restriction endonuclease analysis (REA) and whole-genome sequencing (WGS).

Veterans Affairs hospital and affiliated LTCF.

The study included 29 LTCF residents identified as asymptomatic carriers of toxigenic C. difficile based on every other week perirectal screening and 37 healthcare facility-associated CDI cases (ie, diagnosis >3 days after admission or within 4 weeks of discharge to the community), including 26 hospital-associated and 11 LTCF-associated cases.

Of the 37 CDI cases, 7 (18·9%) were linked to LTCF residents with LTCF-associated CDI or asymptomatic carriage, including 3 of 26 hospital-associated CDI cases (11·5%) and 4 of 11 LTCF-associated cases (36·4%). Of the 7 transmissions linked to LTCF residents, 5 (71·4%) were linked to asymptomatic carriers versus 2 (28·6%) to CDI cases, and all involved transmission of epidemic BI/NAP1/027 strains. No incident hospital-associated CDI cases were linked to other hospital-associated CDI cases.

Our findings suggest that LTCF residents with asymptomatic carriage of C. difficile or CDI contribute to transmission both in the LTCF and in the affiliated hospital during acute-care admissions. Greater emphasis on infection control measures and antimicrobial stewardship in LTCFs is needed, and these efforts should focus on LTCF residents during hospital admissions.

To investigate an outbreak of Pseudomonas aeruginosa infections and colonization in a neonatal intensive care unit.

Infection control assessment, environmental evaluation, and case-control study.

Newly built community-based hospital, 28-bed neonatal intensive care unit.

Neonatal intensive care unit patients receiving care between June 1, 2013, and September 30, 2014.

Case finding was performed through microbiology record review. Infection control observations, interviews, and environmental assessment were performed. A matched case-control study was conducted to identify risk factors for P. aeruginosa infection. Patient and environmental isolates were collected for pulsed-field gel electrophoresis to determine strain relatedness.

In total, 31 cases were identified. Case clusters were temporally associated with absence of point-of-use filters on faucets in patient rooms. After adjusting for gestational age, case patients were more likely to have been in a room without a point-of-use filter (odds ratio [OR], 37.55; 95% confidence interval [CI], 7.16–∞). Case patients had higher odds of exposure to peripherally inserted central catheters (OR, 7.20; 95% CI, 1.75–37.30) and invasive ventilation (OR, 5.79; 95% CI, 1.39–30.62). Of 42 environmental samples, 28 (67%) grew P. aeruginosa. Isolates from the 2 most recent case patients were indistinguishable by pulsed-field gel electrophoresis from water-related samples obtained from these case-patient rooms.

This outbreak was attributed to contaminated water. Interruption of the outbreak with point-of-use filters provided a short-term solution; however, eradication of P. aeruginosa in water and fixtures was necessary to protect patients. This outbreak highlights the importance of understanding the risks of stagnant water in healthcare facilities.

Infect Control Hosp Epidemiol 2017;38:801–808

To develop a method for calculating the number of healthcare-associated infections (HAIs) that must be prevented to reach a HAI reduction goal and identifying and prioritizing healthcare facilities where the largest reductions can be achieved.

Acute care hospitals that report HAI data to the Centers for Disease Control and Prevention’s National Healthcare Safety Network.

The cumulative attributable difference (CAD) is calculated by subtracting a numerical prevention target from an observed number of HAIs. The prevention target is the product of the predicted number of HAIs and a standardized infection ratio goal, which represents a HAI reduction goal. The CAD is a numeric value that if positive is the number of infections to prevent to reach the HAI reduction goal. We calculated the CAD for catheter-associated urinary tract infections for each of the 3,639 hospitals that reported such data to National Healthcare Safety Network in 2013 and ranked the hospitals by their CAD values in descending order.

Of 1,578 hospitals with positive CAD values, preventing 10,040 catheter-associated urinary tract infections at 293 hospitals (19%) with the highest CAD would enable achievement of the national 25% catheter-associated urinary tract infection reduction goal.

The CAD is a new metric that facilitates ranking of facilities, and locations within facilities, to prioritize HAI prevention efforts where the greatest impact can be achieved toward a HAI reduction goal.

Infect. Control Hosp. Epidemiol. 2015;36(12):1379–1384

To investigate an outbreak of New Delhi metallo-β-lactamase (NDM)–producing carbapenem-resistant Enterobacteriaceae (CRE) and determine interventions to interrupt transmission.

Epidemiologic investigation of an outbreak of NDM-producing CRE among patients at a Colorado acute care hospital.

Case patients had NDM-producing CRE isolated from clinical or rectal surveillance cultures (SCs) collected during the period January 1, 2012, through October 20, 2012. Case patients were identified through microbiology records and 6 rounds of SCs in hospital units where they had resided. CRE isolates were tested by real-time polymerase chain reaction for blaNDM. Medical records were reviewed for epidemiologic links; relatedness of isolates was evaluated by pulsed-field gel electrophoresis (PFGE) and whole genome sequencing (WGS). Infection control (IC) was assessed through staff interviews and direct observations.

Two patients were initially identified with NDM-producing CRE during July–August 2012. A third case patient, admitted in May, was identified through microbiology records review. SC identified 5 additional case patients. Patients had resided in 11 different units before identification. All isolates were highly related by PFGE. WGS suggested 3 clusters of CRE. Combining WGS with epidemiology identified 4 units as likely transmission sites. NDM-producing CRE positivity in certain patients was not explained by direct epidemiologic overlap, which suggests that undetected colonized patients were involved in transmission.

A 4-month outbreak of NDM-producing CRE occurred at a single hospital, highlighting the risk for spread of these organisms. Combined WGS and epidemiologic data suggested transmission primarily occurred on 4 units. Timely SC, combined with targeted IC measures, were likely responsible for controlling transmission.

To evaluate national data on healthcare-associated infections (HAIs), device utilization, and antimicrobial resistance in long-term acute care hospitals (LTACHs).

Comparison of data from LTACHs and from medical and medical-surgical intensive care units (ICUs) in short-stay acute care hospitals reporting to the National Healthcare Safety Network (NHSN) during 2010.

Rates of central line–associated bloodstream infections (CLABSIs), catheter-associated urinary tract infections (CAUTIs), and ventilator-associated pneumonia (VAP) as well as device utilization ratios were calculated. For each HAI, pathogen profiles and antimicrobial resistance prevalence were evaluated. Comparisons were made using Poisson regression and the Mood median and x2 tests.

In 2010, 104 LTACHs reported CLABSIs and 57 reported CAUTIs and VAP to the NHSN. Median CLABSI rates in LTACHs (1.25 events per 1,000 device-days reported; range, 0.0-5.96) were comparable to rates in major teaching ICUs and were higher than those in other ICUs. CAUTI rates in LTACHs (median, 2.61; range, 0.0-9.92) were higher and VAP rates (median, 0.0; range, 0.0-3.29) were generally lower than those in ICUs. Central line utilization in LTACHs was higher than that in ICUs, whereas urinary catheter and ventilator utilization was lower. Methicillin resistance among Staphylococcus aureus CLABSIs (83%) and vancomycin resistance among Enterococcus faecalis CAUTIs (44%) were higher in LTACHs than in ICUs. Multidrug resistance among Pseudomonas aeruginosa CAUTIs (25%) was higher in LTACHs than in most ICUs.

CLABSIs and CAUTIs associated with multidrug-resistant organisms present a challenge in LTACHs. Continued HAI surveillance with pathogen-level data can guide prevention efforts in LTACHs.

Infect Control Hosp Epidemiol 2012;33(10):993-1000

To describe a Klebsiella pneumoniae carbapenemase (KPC)–producing carbapenem-resistant Enterobacteriaceae (CRE) outbreak and interventions to prevent transmission.

Epidemiologic investigation of a CRE outbreak among patients at a long-term acute care hospital (LTACH).

Microbiology records at LTACH A from March 2009 through February 2011 were reviewed to identify CRE transmission cases and cases admitted with CRE. CRE bacteremia episodes were identified during March 2009–July 2011. Biweekly CRE prevalence surveys were conducted during July 2010–July 2011, and interventions to prevent transmission were implemented, including education and auditin? of staff and isolation and cohorting of CRE patients with dedicated nursing staff and shared medical equipment. Trends were evaluated using weighted linear or Poisson regression. CRE transmission cases were included in a case-control study to evaluate risk factors for acquisition. A real-time polymerase chain reaction assay was used to detect the blaKPC gene, and pulsed-field gel electrophoresis was performed to assess the genetic relatedness of isolates.

Ninety-nine CRE transmission cases, 16 admission cases (from 7 acute care hospitals), and 29 CRE bacteremia episodes were identified. Significant reductions were observed in CRE prevalence (49% vs 8%), percentage of patients screened with newly detected CRE (44% vs 0%), and CRE bacteremia episodes (2.5 vs 0.0 per 1,000 patient-days). Cases were more likely to have received β-lactams, have diabetes, and require mechanical ventilation. All tested isolates were KPC-producing K. pneumoniae, and nearly all isolates were genetically related.

CRE transmission can be reduced in LTACHs through surveillance testing and targeted interventions. Sustainable reductions within and across healthcare facilities may require a regional public health approach.

Infect Control Hosp Epidemiol 2012;33(10):984-992

Seven organ/space surgical site infections (SSIs) that occurred after arthroscopic procedures and were due to Pseudomonas aeruginosa of indistinguishable pulsed-field gel electrophoresis (PFGE) patterns occurred at hospital X in Texas from April 22, 2009, through May 7, 2009.

To determine the source of the outbreak and prevent future infections.

Infection control observations and a case-control study.

Laboratory records were reviewed for case finding. A case-control study was conducted. A case patient was defined as someone who underwent knee or shoulder arthroscopy at hospital X during the outbreak period and subsequently developed organ/space SSI due toP. aeruginosa. Cultures of environmental and surgical equipment samples were performed, and selected isolates were analyzed by PFGE. Surgical instrument reprocessing practices were reviewed, and surgical instrument lumens were inspected with a borescope after reprocessing to assess cleanliness.

The case-control study did not identify any significant patient-related or operator-related risk factors. P. aeruginosa grew from 62 of 388 environmental samples. An isolate from the gross decontamination sink had a PFGE pattern that was indistinguishable from that of the case patient isolates. All surgical instrument cultures showed no growth. Endoscopic evaluation of reprocessed arthroscopic equipment revealed retained tissue in the lumen of both the inflow/outflow cannulae and arthroscopic shaver handpiece. No additional cases occurred after changes in instrument reprocessing protocols were implemented. After this outbreak, the US Food and Drug Administration released a safety alert about the concern regarding retained tissue within arthroscopic shavers.

These SSIs were likely related to surgical instrument contamination with P. aeruginosa during instrument reprocessing. Retained tissue in inflow/outflow cannulae and shaver handpieces could have allowed bacteria to survive sterilization procedures.

Over the past 2 decades, multiple interventions have been developed to prevent catheter-associated urinary tract infections (CAUTIs). The CAUTI prevention guidelines of the Healthcare Infection Control Practices Advisory Committee were recently revised.

To examine changes in rates of CAUTI events in adult intensive care units (ICUs) in the United States from 1990 through 2007.

Data were reported to the Centers for Disease Control and Prevention (CDC) through the National Nosocomial Infections Surveillance System from 1990 through 2004 and the National Healthcare Safety Network from 2006 through 2007. Infection preventionists in participating hospitals used standard methods to identify all CAUTI events (categorized as symptomatic urinary tract infection [SUTI] or asymptomatic bacteriuria [ASB]) and urinary catheter–days (UC-days) in months selected for surveillance. Data from all facilities were aggregated to calculate pooled mean annual SUTI and ASB rates (in events per 1,000 UC-days) by ICU type. Poisson regression was used to estimate percent changes in rates over time.

Overall, 36,282 SUTIs and 22,973 ASB episodes were reported from 367 facilities representing 1,223 adult ICUs, including combined medical/surgical (505), medical (212), surgical (224), coronary (173), and cardiothoracic (109) ICUs. All ICU types experienced significant declines of 19%–67% in SUTI rates and 29%–72% in ASB rates from 1990 through 2007. Between 2000 and 2007, significant reductions in SUTI rates occurred in all ICU types except cardiothoracic ICUs.

Since 1990, CAUTI rates have declined significantly in all major adult ICU types in facilities reporting to the CDC. Further efforts are needed to assess prevention strategies that might have led to these decreases and to implement new CAUTI prevention guidelines.

Carbapenem-resistant Klebsiella pneumoniae (CRKP) is resistant to almost all antimicrobial agents, and CRKP infections are associated with substantial morbidity and mortality.

To describe an outbreak of CRKP in Puerto Rico, determine risk factors for CRKP acquisition, and detail the successful measures taken to control the outbreak.

Two case-control studies.

A 328-bed tertiary care teaching hospital.

Twenty-six CRKP case patients identified during the outbreak period of February through September 2008, 26 randomly selected uninfected control patients, and 26 randomly selected control patients with carbapenem-susceptible K. pneumoniae (CSKP) hospitalized during the same period.

We performed active case finding, including retrospective review of the hospital's microbiology database and prospective perirectal surveillance culture sampling in high-risk units. Case patients were compared with each control group while controlling for time at risk. We sequenced the blaKPC gene with polymerase chain reaction for 7 outbreak isolates and subtyped these isolates with pulsed-field gel electrophoresis.

In matched, multivariable analysis, the presence of wounds (hazard ratio, 19.0 [95% confidence interval {CI}, 2.5-142.0]) was associated with CRKP compared with no K. pneumoniae. Transfer between units (adjusted odds ratio [OR], 7.5 [95% CI, 1.8-31.1]), surgery (adjusted OR, 4.0 [95% CI, 1.0-15.7]), and wounds (adjusted OR, 4.9 [95% CI, 1.1-21.8]) were independent risk factors for CRKP compared to CSKP. A novel K. pneumoniae carbapenemase variant (KPC-8) was present in 5 isolates. Implementation of active surveillance for CRKP colonization and cohorting of CRKP patients rapidly controlled the outbreak.

Enhanced surveillance for CRKP colonization and intensified infection control measures that include limiting the physical distribution of patients can reduce CRKP transmission during an outbreak.