To determine whether reuse of insulin pens among multiple patients resulted in transmission of bloodborne pathogens (BBP).

Retrospective cohort study.

Two Veterans Affairs medical centers.

Veterans who received insulin via insulin pens from 2010 to 2013.

Patients were identified through electronic health records, notified of possible exposure, and serotested for human immunodeficiency virus, hepatitis C virus (HCV), and hepatitis B virus. Newly discovered case patients were assessed in relation to potential proximate patients to determine viral strain relatedness by HCV envelope (env) gene sequencing.

Of 1,791 hospitalized veterans who received insulin via insulin pen, 1,155 were tested for at least 1 viral infection after exposure. Of these, 67 patients were newly diagnosed with 1 or more viral BBPs. For human immunodeficiency virus and hepatitis B virus no additional strain testing of case or proximate patients was possible; 8 HCV cases and 45 proximates (40 unique patients; 5 patients were positive for 2 genotypes) were identified as needing strain testing. Only 3 cases and their 19 proximates had samples available for further testing. None of the 26 remaining proximate patients had blood available for further testing. Median genetic distance between the HCV env sequences of those available for additional testing ranged from 14% to 24%, indicating nonrelatedness.

Our investigation revealed that exposure to insulin pen reuse did not result in HCV transmission among patients who had viral genetic analysis performed. Analysis for any additional potential transmission of blood-borne pathogens was limited by the available samples.

Infect Control Hosp Epidemiol 2015;36(10):1121–1129

Hospital environments influence healthcare-associated infection (HAI) patterns, but the role of evidenced-based design (EBD) and residual bacterial DNA (previously thought to be clinically inert) remain incompletely understood.

In a newly built EBD hospital, we used culture-based and culture-free (molecular) assays, pulsed-field gel electrophoresis (PFGE), and whole-genome sequencing (WGS) to determine: (1) patterns of environmental contamination with target organisms (TOs) and multidrug-resistant (MDR) target organisms (MDR-TOs); (2) genetic relatedness between environmentally isolated MDR-TO and those from HAIs; and (3) correlation between surface contamination and HAIs.

A total of 1,273 high-touch surfaces were swabbed before and after terminal cleaning during 77 room visits. Of the 2,546 paired swabs, 47% had cultivable biomaterial and 42% had PCR-amplifiable DNA. The ratios of TOs detected to surfaces assayed were 85 per 1,273 for the culture-based method and 106 per 1,273 for the PCR-based method. Sinks, toilet rails, and bedside tables most frequently harbored biomaterial. Although cleaned surfaces were less likely to have cultivable TOs than precleaned surfaces, they were not less likely to harbor bacterial DNA. The rate of MDR-TOs to surfaces swabbed was 0.1% (3/2546). Although environmental MDR-TOs and MDR-TOs from HAIs were genetically related by PFGE, WGS revealed that they were unrelated. Environmental levels of cultivable Enterococcus spp. and E. coli DNA were positively correlated with infection incidences (P<.04 and P<.005, respectively).

MDR-TOs were rarely detected during surveillance and were not implicated in HAIs. The roles of environmental DNA and EBD, particularly with respect to water-associated fixtures or the potential suppression of cultivable environmental MDR-TOs, warrant multicenter investigations.

Infect Control Hosp Epidemiol 2015;36(10):1130–1138

Targeted surveillance has focused on device-associated infections and surgical site infections (SSIs) and is often limited to healthcare-associated infections (HAIs) in high-risk areas. Longitudinal trends in all HAIs, including other types of HAIs, and HAIs outside of intensive care units (ICUs) remain unclear. We examined the incidences of all HAIs using comprehensive hospital-wide surveillance over a 12-year period (2001–2012).

This retrospective observational study was conducted at the University of North Carolina (UNC) Hospitals, a tertiary care academic facility. All HAIs, including 5 major infections with 14 specific infection sites as defined using CDC criteria, were ascertained through comprehensive hospital-wide surveillance. Generalized linear models were used to examine the incidence rate difference by infection type over time.

A total of 16,579 HAIs included 6,397 cases in ICUs and 10,182 cases outside ICUs. The incidence of overall HAIs decreased significantly hospital-wide (−3.4 infections per 1,000 patient days), in ICUs (−8.4 infections per 1,000 patient days), and in non-ICU settings (−1.9 infections per 1,000 patient days). The incidences of bloodstream infection, urinary tract infection, and pneumonia in hospital-wide settings decreased significantly, but the incidences of SSI and lower respiratory tract infection remained unchanged. The incidence of Clostridium difficile infection (CDI) increased remarkably. The outcomes were estimated to include 700 overall HAIs prevented, 40 lives saved, and cost savings in excess of $10 million.

We demonstrated success in reducing overall HAIs over a 12-year period. Our data underscore the necessity for surveillance and infection prevention interventions outside of the ICUs, for non–device-associated HAIs, and for CDI.

Infect Control Hosp Epidemiol 2015;36(10):1139–1147

Prevalence of blaKPC-encoding Enterobacteriaceae (KPC) in Chicago long-term acute care hospitals (LTACHs) rose rapidly after the first recognition in 2007. We studied the epidemiology and transmission capacity of KPC in LTACHs and the effect of patient cohorting.

Data were available from 4 Chicago LTACHs from June 2012 to June 2013 during a period of bundled interventions. These consisted of screening for KPC rectal carriage, daily chlorhexidine bathing, medical staff education, and 3 cohort strategies: a pure cohort (all KPC-positive patients on 1 floor), single rooms for KPC-positive patients, and a mixed cohort (all KPC-positive patients on 1 floor, supplemented with KPC-negative patients). A data-augmented Markov chain Monte Carlo (MCMC) method was used to model the transmission process.

Average prevalence of KPC colonization was 29.3%. On admission, 18% of patients were colonized; the sensitivity of the screening process was 81%. The per admission reproduction number was 0.40. The number of acquisitions per 1,000 patient days was lowest in LTACHs with a pure cohort ward or single rooms for colonized patients compared with mixed-cohort wards, but 95% credible intervals overlapped.

Prevalence of KPC in LTACHs is high, primarily due to high admission prevalence and the resultant impact of high colonization pressure on cross transmission. In this setting, with an intervention in place, patient-to-patient transmission is insufficient to maintain endemicity. Inclusion of a pure cohort or single rooms for KPC-positive patients in an intervention bundle seemed to limit transmission compared to use of a mixed cohort.

Infect Control Hosp Epidemiol 2015;36(10):1148–1154

To characterize the epidemiology of multidrug-resistant (MDR) Acinetobacter baumannii colonization in high-risk nursing home (NH) residents.

Nested case-control study within a multicenter prospective intervention trial.

Four NHs in Southeast Michigan.

Case patients and control subjects were NH residents with an indwelling device (urinary catheter and/or feeding tube) selected from the control arm of the Targeted Infection Prevention study. Cases were residents colonized with MDR (resistant to ≥3 classes of antibiotics) A. baumannii; controls were never colonized with MDR A. baumannii.

For active surveillance cultures, specimens from the nares, oropharynx, groin, perianal area, wounds, and device insertion site(s) were collected upon study enrollment, day 14, and monthly thereafter. A. baumannii strains and their susceptibilities were identified using standard microbiologic methods.

Of 168 NH residents, 25 (15%) were colonized with MDR A. baumannii. Compared with the 143 controls, cases were more functionally disabled (Physical Self-Maintenance Score >24; odds ratio, 5.1 [95% CI, 1.8–14.9]; P<.004), colonized with Proteus mirabilis (5.8 [1.9–17.9]; P<.003), and diabetic (3.4 [1.2–9.9]; P<.03). Most cases (22 [88%]) were colonized with multiple antibiotic-resistant organisms and 16 (64%) exhibited co-colonization with at least one other resistant gram-negative bacteria.

Functional disability, P. mirabilis colonization, and diabetes mellitus are important risk factors for colonization with MDR A. baumannii in high-risk NH residents. A. baumannii exhibits widespread antibiotic resistance and a preference to colonize with other antibiotic-resistant organisms, meriting enhanced attention and improved infection control practices in these residents.

Infect Control Hosp Epidemiol 2015;36(10):1155–1162

Whether contact precautions (CP) are required to control the endemic transmission of methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococcus (VRE) in acute care hospitals is controversial in light of improvements in hand hygiene, MRSA decolonization, environmental cleaning and disinfection, fomite elimination, and chlorhexidine bathing.

To provide a framework for decision making around use of CP for endemic MRSA and VRE based on a summary of evidence related to use of CP, including impact on patients and patient care processes, and current practices in use of CP for MRSA and VRE in US hospitals.

A literature review, a survey of Society for Healthcare Epidemiology of America Research Network members on use of CP, and a detailed examination of the experience of a convenience sample of hospitals not using CP for MRSA or VRE.

Hospital epidemiologists and infection prevention experts.

No high quality data support or reject use of CP for endemic MRSA or VRE. Our survey found more than 90% of responding hospitals currently use CP for MRSA and VRE, but approximately 60% are interested in using CP in a different manner. More than 30 US hospitals do not use CP for control of endemic MRSA or VRE.

Higher quality research on the benefits and harms of CP in the control of endemic MRSA and VRE is needed. Until more definitive data are available, the use of CP for endemic MRSA or VRE in acute care hospitals should be guided by local needs and resources.

Infect Control Hosp Epidemiol 2015;36(10):1163–1172

Infections cause morbidity and mortality in neonatal intensive care units (NICUs). The association between nursery design and nosocomial infections is unclear.

To determine whether rates of colonization by methicillin-resistant Staphylococcus aureus (MRSA), late-onset sepsis, and mortality are reduced in single-patient rooms.

Retrospective cohort study.

NICU in a tertiary referral center.

Our NICU is organized into single-patient and open-unit rooms. Clinical data sets including bed location and microbiology results were examined over 29 months. Differences in outcomes between bed configurations were determined by χ2 and Cox regression.

All NICU patients.

Among 1,823 patients representing 55,166 patient-days, single-patient and open-unit models had similar incidences of MRSA colonization and MRSA colonization-free survival times. Average daily census was associated with MRSA colonization rates only in single-patient rooms (hazard ratio, 1.31; P=.039), whereas hand hygiene compliance on room entry and exit was associated with lower colonization rates independent of bed configuration (hazard ratios, 0.834 and 0.719 per 1% higher compliance, respectively). Late-onset sepsis rates were similar in single-patient and open-unit models as were sepsis-free survival and the combined outcome of sepsis or death. After controlling for demographic, clinical, and unit-based variables, multivariate Cox regression demonstrated that bed configuration had no effect on MRSA colonization, late-onset sepsis, or mortality.

MRSA colonization rate was impacted by hand hygiene compliance, regardless of room configuration, whereas average daily census affected only infants in single-patient rooms. Single-patient rooms did not reduce the rates of MRSA colonization, late-onset sepsis, or death.

Infect Control Hosp Epidemiol 2015;36(10):1173–1182

The incidence of Clostridium difficile infection (CDI) has increased and has been associated with poor outcomes among hospitalized children, including increased risk of death. The purpose of this study was to identify risk factors for all-cause in-hospital mortality among children with CDI.

A multicenter cohort of children with CDI, aged 1–18 years, was established among children hospitalized at 41 freestanding children’s hospitals between January 1, 2006 and August 31, 2011. Children with CDI were identified using a validated case-finding tool (ICD-9-CM code for CDI plus C. difficile test charge). Only the first CDI-related hospitalization during the study period was used. Risk factors for all-cause in-hospital mortality within 30 days of C. difficile test were evaluated using a multivariable logistic regression model.

We identified 7,318 children with CDI during the study period. The median age of this cohort was 6 years [interquartile range (IQR): 2–13]; the mortality rate was 1.5% (n=109); and the median number of days between C. difficile testing and death was 12 (IQR, 7–20). Independent risk factors for death included older age [adjusted odds ratio (OR, 95% confidence interval), 2.29 (1.40–3.77)], underlying malignancy [3.57 (2.36–5.40)], cardiovascular disease [2.06 (1.28–3.30)], hematologic/immunologic condition [1.89 (1.05–3.39)], gastric acid suppression [2.70 (1.43–5.08)], and presence of >1 severity of illness marker [3.88 (2.44–6.19)].

Patients with select chronic conditions and more severe disease are at increased risk of death. Identifying risk factors for in-hospital mortality can help detect subpopulations of children that may benefit from targeted CDI prevention and treatment strategies.

Infect Control Hosp Epidemiol 2015;36(10):1183–1189

To describe and compare the mortality associated with nosocomial pneumonia due to Pseudomonas aeruginosa (Pa-NP) according to pneumonia classification (community-onset pneumonia [COP], hospital-acquired pneumonia [(HAP], and ventilator-associated pneumonia [VAP]).

We conducted a retrospective cohort study of adults with Pa-NP. We compared mortality for Pa-NP among patients with COP, HAP, and VAP and used logistic regression to identify risk factors for hospital mortality and inappropriate initial antibiotic therapy (IIAT).

Twelve acute care hospitals in 5 countries (United States, 3; France, 2; Germany, 2; Italy, 2; and Spain, 3).

A total of 742 patients with Pa-NP.

Hospital mortality was greater for those with VAP (41.9%) and HAP (40.1%) compared with COP (24.5%) (P<.001). In multivariate analyses, independent predictors of hospital mortality differed by pneumonia classification (COP: need for mechanical ventilation and intensive care; HAP: multidrug-resistant isolate; VAP: IIAT, increasing age, increasing Charlson comorbidity score, bacteremia, and use of vasopressors). Presence of multidrug resistance was identified as an independent predictor of IIAT for patients with COP and HAP, whereas recent antibiotic administration was protective in patients with VAP.

Among patients with Pa-NP, pneumonia classification identified patients with different risks for hospital mortality. Specific risk factors for hospital mortality also differed by pneumonia classification and multidrug resistance appeared to be an important risk factor for IIAT. These findings suggest that pneumonia classification for P. aeruginosa identifies patients with different mortality risks and specific risk factors for outcome and IIAT.

Infect Control Hosp Epidemiol 2015;36(10):1190–1197

Hip or knee arthroplasty infection (HKAI) leads to heavy medical consequences even if rare.

To assess the routine use of a hospital discharge detection algorithm of prosthetic joint infection as a novel additional tool for surveillance.

A historic 5-year cohort study was built using a hospital database of people undergoing a first hip or knee arthroplasty in 1 French region (2.5 million inhabitants, 39 private and public hospitals): 32,678 patients with arthroplasty code plus corresponding prosthetic material code were tagged. HKAI occurrence was then tracked in the follow-up on the basis of a previously validated algorithm using International Statistical Classification of Disease, Tenth Revision, codes as well as the surgical procedures coded. HKAI density incidence was estimated during the follow-up (up to 4 years after surgery); risk factors were analyzed using Cox regression.

A total of 604 HKAI patients were identified: 1-year HKAI incidence was1.31%, and density incidence was 2.2/100 person-years in hip and 2.5/100 person-years in knee. HKAI occurred within the first 30 days after surgery for 30% but more than 1 year after replacement for 29%. Patients aged 75 years or older, male, or having liver diseases, alcohol abuse, or ulcer sore had higher risk of infection. The inpatient case fatality in HKAI patients was 11.4%.

The hospital database method used to measure occurrence and risk factors of prosthetic joint infection helped to survey HKAI and could optimize healthcare delivery.

Infect Control Hosp Epidemiol 2015;36(10):1198–1207

Healthcare-associated infection rates are higher in low- and middle-income countries compared with high-income countries, resulting in relatively larger incidence of patient mortality and disability and additional healthcare costs.

To use the Infection Control Assessment Tool to assess gaps in infection control (IC) practices in the participating countries.

Six international sites located in Argentina, Greece, Hungary, India, Nepal, and South Africa provided information on the health facility and the surgical modules relating to IC programs, surgical antibiotic use and surgical equipment procedures, surgical area practices, sterilization and disinfection of equipment and intravenous fluid, and hand hygiene. Modules were scored for each country.

The 6 international sites completed 5 modules. Of 121 completed sections, scores of less than 50% of the recommended IC practices were received in 23 (19%) and scores from 50% to 75% were received in 43 (36%). IC programs had various limitations in many sites and surveillance of healthcare-associated infections was not consistently performed. Lack of administration of perioperative antibiotics, inadequate sterilization and disinfection of equipment, and paucity of hand hygiene were found even in a high-income country. There was also a lack of clearly written defined policies and procedures across many facilities.

Our results indicate that adherence to recommended IC practices is suboptimal. Opportunities for improvement of IC practices exist in several areas, including hospital-wide IC programs and surveillance, antibiotic stewardship, written and posted guidelines and policies across a range of topics, surgical instrument sterilization procedures, and improved hand hygiene.

Infect. Control Hosp. Epidemiol. 2015;36(10):1208–1214