Although influenza vaccination of healthcare workers reduces influenza-like illness and overall mortality among patients, national rates of vaccination for healthcare providers are unacceptably low. We report the implementation of a new mandatory vaccination policy by means of a streamlined electronic enrollment and vaccination tracking system at the National Institutes of Health (NIH) Clinical Center.

To evaluate the outcome of a new mandatory staff influenza vaccination program.

A new hospital policy endorsed by all the component NIH institutes and the Clinical Center departments mandated that employees who have patient contact either be vaccinated annually against influenza or sign a declination specifying the reason(s) for refusal. Those who fail to comply would be required to appear before the Medical Executive Committee to explain their rationale. We collected in a database the names of all physician and nonphysician staff who had patient contact. When a staff member either was vaccinated or declined vaccination, a simple system of badge scanning and bar-coded data entry captured essential data. The database was continuously updated, and it provided a list of noncompliant employees with whom to follow up.

By February 12, 2009, all 2,754 identified patient-care employees either were vaccinated or formally declined vaccination. Among those, 2,424 (88%) were vaccinated either at the NIH or elsewhere, 36 (1.3%) reported medical contraindications, and 294 (10.7%) declined vaccination for other reasons. Among the 294 employees without medical contraindications who declined, the most frequent reason given for declination was concern about side effects.

Implementation of a novel vaccination tracking process and a hospital policy requiring influenza vaccination or declination yielded dramatic improvement in healthcare worker vaccination rates and likely will result in increased patient safety in our hospital.

Intensive care units (ICUs) are potential high-risk areas for the transmission of respiratory viruses such as influenza. An influenza pandemic is expected to result in a dramatic surge of critically ill patients, and ICU healthcare workers (HCW) are likely to be at high risk of infection.

To characterize the knowledge, attitudes, and expected behaviors of ICU HCWs concerning the risk of and response to an influenza pandemic.

A survey was distributed to 292 HCWs (ie, internal medicine house staff, pulmonary and critical care fellows and faculty members, nurses, and respiratory care professionals) at 2 hospitals in Baltimore, Maryland.

Of the 292 HCWs, 256 (88%) completed the survey. Just over one-half of the respondents believed there is at least a 45% chance of an influenza pandemic within the next 5 years. However, only 41% reported knowing how to protect themselves during an outbreak. Despite this common belief that a pandemic is likely in the near future, 59% of those surveyed reported only minimal knowledge of the risks of and protective strategies for an influenza pandemic, and 20% reported being unlikely to report to work during a pandemic or being unsure about whether they would do so. The odds of reporting to work varied on the basis of race and responsibility for child care.

ICU HCWs reported having minimal knowledge concerning the risk of and response to an influenza pandemic, even though more that one-half of HCWs expect that a pandemic will occur in the near future. This finding in a high-risk setting is of concern, given that lack of knowledge among HCWs may result in increased nosocomial transmission to HCWs and patients. Interventions to improve knowledge of pandemics and understanding of risks among ICU HCWs are essential.

To characterize practices related to measuring influenza vaccination rates among healthcare personnel in US hospitals.

Descriptive survey.

Nonfederal, short-stay hospitals that provide general medical and surgical services, identified by use of the 2004 American Hospital Association Annual Survey Database.

Healthcare personnel from 996 randomly sampled US hospitals stratified by region and bed size.

A self-administered questionnaire was distributed in 2006 to infection control coordinators to gather data on policies and practices related to the provision of the influenza vaccine and on the measurement and reporting of influenza vaccination rates. Descriptive statistics and associations were calculated, and logistic regression was conducted.

The response rate was 56% (ie, 555 of 996 US hospitals responded to the questionnaire). Weighting accounted for sampling design and nonresponse. Most hospitals provided the influenza vaccine to employees (100%), credentialed medical staff (ie, independent practitioners; 94%), volunteers (86%), and contract staff (83%); provision for students and residents was less frequent (58%). Only 69% of hospitals measured vaccination rates (mean coverage rate, 55%). Most hospitals that measured coverage included employees (98%) in the vaccination rates, whereas contract staff (53%), credentialed medical staff (56%), volunteers (56%), and students and residents (30%) were less commonly included. Among hospitals measuring coverage, 44% included persons for which vaccine was contraindicated, and 51% included persons who refused vaccination. After adjustment for region and size, hospitals with vaccination plans written into policy (odds ratio, 2.0 [95% confidence interval, 1.22–7.67]) or that addressed internally reporting coverage (odds ratio, 4.8 [95% confidence interval, 2.97–7.66]) were more likely to measure coverage than were hospitals without such plans.

Hospitals vary in terms of the groups of individuals included in influenza vaccination coverage measurements. Standardized measures may improve comparability of hospital-reported vaccination rates. Measuring coverage in a manner that facilitates identification of occupational groups with low vaccination rates may inform development of targeted interventions.

Methicillin-resistant Staphylococcus aureus (MRSA) can cause severe infection in patients who are undergoing vascular surgical operations. Testing all vascular surgery patients preoperatively for MRSA and attempting to decolonize those who have positive results may be a strategy to prevent MRSA infection. The economic value of such a strategy has not yet been determined.

We developed a decision-analytic computer simulation model to determine the economic value of using such a strategy before all vascular surgical procedures from the societal and third-party payer perspectives at different MRSA prevalence and decolonization success rates.

The model showed preoperative MRSA testing to be cost-effective (incremental cost-effectiveness ratio, <$50,000 per quality-adjusted life year) when the MRSA prevalence is ≥0.01 and the decolonization success rate is ≥0.25. In fact, this strategy was dominant (ie, less costly and more effective) at the following thresholds: MRSA prevalence ≥0.01 and decolonization success rate ≥0.5, and MRSA prevalence ≥0.025 and decolonization success rate ≥0.25.

Testing and decolonizing patients for MRSA before vascular surgery may be a cost-effective strategy over a wide range of MRSA prevalence and decolonization success rates.

To describe a pseudo-outbreak of Clostridium difficile infection (CDI) caused by a faulty toxin assay lot and to determine the effect of sensitivity, specificity, and repeated testing for C. difficile on perceived CDI burden, positive predictive value, and false-positive results.

Outbreak investigation and criterion standard.

Patients hospitalized at a tertiary care hospital who had at least 1 toxin assay for detection of C. difficile performed during the period from July 1, 2004, through June 30, 2006.

The run control chart method and the x2 test were used to compare CDI rates and the proportion of positive test results before, during, and after the pseudo-outbreak. The effect of repeated testing was evaluated by using 3 hypothetical models with a sample of 10,000 patients and various assay sensitivity and specificity estimates.

In November of 2005, the CDI rate at the hospital increased from 1.5 to 2.6 cases per 1,000 patient-days (P< .01), and the proportion of positive test results increased from 13.6% to 22.1% (P< .01). An investigation revealed a pseudo-outbreak caused by a faulty toxin assay lot. A decrease of only 1.2% in the specificity of the toxin assay would result in a 32% increase in perceived incidence of CDI at this institution. When calculated by use of the manufacturer's stated specificity and sensitivity and this institution's testing practices, the positive predictive value of the test decreased from 80.6% to 4.1% for patients who received 3 tests.

Specificity is as important as sensitivity when testing for CDI. False-positive CDI cases can drain hospital resources and adversely affect patients. Repeated testing for C. difficile should be performed with caution.

To characterize the clinical and molecular epidemiology of multidrug-resistant (MDR) organisms in residents, in healthcare workers (HCWs), and on inanimate surfaces at a long-term care facility (LTCF).

Point-prevalence study in 4 separate wards at a 600-bed urban LTCF that was conducted from October 31, 2006 through February 5, 2007.

One hundred sixty-one LTCF residents and 13 HCWs.

Nasal and rectal samples were obtained for culture from each resident, selected environmental surfaces in private and common rooms, and the hands and clothing of HCWs in each ward. All cultures were evaluated for the presence of MDR gram-negative bacteria, methicillin-resistant Staphylococcus aureus, and vancomycin-resistant enterococci. Clinical and demographic information were collected for each enrolled resident. Molecular typing was performed to identify epidemiologically related strains.

A total of 37 (22.8%), 1 (0.6%), and 18 (11.1%) residents were colonized with MDR gram-negative bacteria, vancomycin-resistant enterococci, and methicillin-resistant S. aureus, respectively. MDR gram-negative bacteria were recovered from 3 (1.8%) of the 175 environmental samples cultured, all of which were obtained from common areas in LTCF wards. One (7.7%) of the 13 HCWs harbored MDR gram-negative bacteria. Molecular typing identified clonally related MDR gram-negative strains in LTCF residents. After multivariable analysis, length of hospital stay of at least 4 years, fecal incontinence, and antibiotic exposure for at least 8 days were independent risk factors associated with harboring MDR gram-negative bacteria among LTCF residents.

The prevalence of MDR gram-negative bacteria is high among LTCF residents and exceeds that of vancomycin-resistant enterococci and methicillin-resistant S. aureus. Common areas in LTCFs may provide a unique opportunity for person-to-person transmission of MDR gram-negative bacteria.

Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae is an emerging pathogen with serious clinical and infection control implications. To our knowledge, no study has specifically examined risk factors for KPC-producing K. pneumoniae or its impact on mortality.

To identify risk factors for infection or colonization with KPC-producing K. pneumoniae, a case-control study was performed. Case patients with KPC-producing K. pneumoniae were compared with control subjects with carbapenem-susceptible K. pneumoniae. A cohort study evaluated the association between KPC-producing K. pneumoniae and in-hospital mortality.

Fifty-six case patients and 863 control subjects were identified. In multivariable analysis, independent risk factors for KPC-producing K. pneumoniae were (1) severe illness (adjusted odds ratio [AOR], 4.31; 95% confidence interval [CI], 2.25–8.25), (2) prior fluoroquinolone use (AOR, 3.39; 95% CI, 1.50, 7.66), and (3) prior extended-spectrum cephalosporin use (AOR, 2.55; 95% CI, 1.18, 5.52). Compared with samples from other anatomic locations, K. pneumoniae isolates from blood samples were less likely to harbor KPC (AOR, 0.33; 95% CI, 0.12, 0.86). KPC-producing K. pneumoniae was independently associated with in-hospital mortality (AOR, 3.60; 95% CI, 1.87–6.91).

KPC-producing K. pneumoniae is an emerging pathogen associated with significant mortality. Our findings highlight the urgent need to develop strategies for prevention and infection control. Limiting use of certain antimicrobials, specifically fluoroquinolones and cephalosporins, use may be effective strategies.

Acinetobacter baumannii is an emerging gram-negative pathogen that can cause healthcare-acquired infections among patients. Treatment is complicated for cases of healthcare-acquired infection with A. baumannii resistant to imipenem.

To elucidate the risk factors for imipenem-resistant A. baumannii (IRAB) infection or colonization and to identify the effect of resistance on clinical and economic outcomes.

We analyzed data from 2 medical centers of the University of Pennsylvania. Longitudinal trends in the prevalence of IRAB clinical isolates were characterized during the period from 1989 through 2004. For A. baumannii isolates obtained from 2001 through 2006, a case-control study was conducted to investigate the association between prior carbapenem use and IRAB infection or colonization, and a cohort study was performed to identify the effect of IRAB infection or colonization on mortality, length of stay after culture, and hospital cost after culture.

From 1989 through 2004, the annual prevalence of IRAB isolates ranged from 0% to 21%. During the period from 2001 through 2006, there were 386 unique patients with A. baumannii isolates, and 89 (23.1%) had IRAB isolates. Prior carbapenem use was independently associated with IRAB infection or colonization (adjusted odds ratio, 3.04 [95% confidence interval, 1.07–8.65]). There was a borderline significant association between IRAB infection or colonization and mortality, although this association was limited to isolates recovered from blood samples (adjusted odds ratio, 5.30 [95% confidence interval, 0.81–34.59]). Compared with patients with imipenem-susceptible A. baumannii infection or colonization, patients with IRAB infection or colonization had a longer hospital stay after culture (median, 21 vs 16 days; P = .07) and greater hospital charges after culture (mean, $334,516 vs $276,059; P = .03). After controlling for patient location in an intensive care unit, transfer from another facility, and length of hospital stay before culture, there was no longer an independent association between IRAB infection or colonization and higher cost after culture and length of stay after positive culture result.

Many A. baumannii isolates exhibit imipenem resistance, which is strongly associated with prior use of carbapenems. Given the high mortality rate associated with A. baumannii infection or colonization, interventions to curb further emergence of cases of IRAB infection and strategies to optimize therapy are needed.

The aim of this study was to determine potential risk factors for mortality in patients with nosocomial Stenotrophomonas maltophilia pneumonia.

A retrospective, single-center, observational study.

A 2400-bed tertiary teaching hospital in southern Taiwan.

This retrospective study evaluated patients (age, at least 18 years) with nosocomial pneumonia (S. maltophilia isolated from respiratory culture) who were seen at Kaohsiung Chang Gung Memorial Hospital over a 3-year period. A total of 406 patients (64% male, mean age ± standard deviation, 69.6 ± 14.93 years; mean duration of hospital stay ± standard deviation, 57.5 ± 39.47 days) were included.

Most index isolates (53.9%) were from the first sample cultured. Polymicrobial isolates were cultured from samples from 177 (43.6%) of the 406 study patients. The most common copathogen was Pseudomonas aeruginosa (53.11% of isolates). The all-cause hospital mortality rate was 42.6% (173 deaths among 406 patients). Survivors had a shorter time from admission to a positive index culture result than did nonsurvivors (26.1 vs 31.7 days; P = .04). Mortality was significantly higher among patients with malignancy (adjusted odds ratio [AOR], 2.48; 95% confidence interval [CI], 1.52–4.07; P < .001 ), renal disease (AOR, 2.6; 95% CI, 1.51–4.47; P = .001), intensive care unit stay (AOR, 1.72; 95% CI, 1.1–2.7; P = .018), and inadequate initial empirical antibiotic therapy (AOR, 2.17; 95% CI, 1.4–3.38; P = .001).

S. maltophilia pneumonia is associated with a high mortality rate and is commonly associated with concomitant polymicrobial colonization or infection. Underlying comorbidities and inadequate initial empirical antibiotic therapy substantially account for increased mortality rates.

Healthcare-associated infections are likely to be caused by drug-resistant and possibly mixed organisms and to be treated with inappropriate antibiotics. Because prompt appropriate treatment is associated with better outcomes, we studied the epidemiology of healthcare-associated complicated skin and skin-structure infections (cSSSIs).

Persons hospitalized with cSSSI and a positive culture result.

We conducted a single-center retrospective cohort study from April 2006 through December 2007. We differentiated healthcare-associated from community-acquired cSSSIs by at least 1 of the following risk factors: (1) recent hospitalization, (2) recent antibiotics, (3) hemodialysis, and (4) transfer from a nursing home. Inappropriate treatment was defined as no antimicrobial therapy with activity against the offending pathogen(s) within 24 hours after collection of a culture specimen. Mixed infections were those caused by both a gram-positive and a gram-negative organism.

Among 717 hospitalized patients with cSSSI, 527 (73.5%) had healthcare-associated cSSSI. Gram-negative organisms were more common (relative risk, 1.24 [95% confidence interval, 1.14–1.35) and inappropriate treatment trended toward being more common (odds ratio, 1.29 [95% confidence interval, 0.85–1.95]) in healthcare-associated cSSSI than in community-acquired cSSSI. Mixed cSSSIs occurred in 10.6% of patients with healthcare-associated cSSSI and 6.3% of those with community-acquired cSSSI (P = .082) and were more likely to be treated inappropriately than to be nonmixed infections (odds ratio, 2.42 [95% confidence interval, 1.43–4.10]). Both median length of hospital stay (6.2 vs 2.9 days; P < .001) and mortality rate (6.6% vs 1.1%; P = .003) were significantly higher for healthcare-associated cSSSI than community-acquired cSSSI.

Healthcare-associated cSSSIs are common and are likely to be caused by gram-negative organisms. Mixed infections carry a <2-fold greater risk of inappropriate treatment. Healthcare-associated cSSSIs are associated with increased mortality and prolonged length of hospital stay, compared with community-acquired cSSSIs.

To describe the prevalence, characteristics, and barriers to implementation of antimicrobial stewardship programs (ASPs) in pediatrics.

In December 2008, we surveyed the pediatric members of the Emerging Infections Network, a network of infectious diseases consultants located throughout North America. Participants responded regarding whether their hospital had or planned to develop an ASP, its characteristics, barriers to improvement or implementation, and perceptions about antimicrobial resistance.

Of 246 pediatric infectious disease consultants surveyed, 147 (60%) responded. Forty-five respondents (33%) reported having an ASP, and 25 (18%) were planning a program. The percentage of respondents from freestanding children's hospitals who were planning ASPs was higher than the percentage of respondents from other settings who were planning ASPs (P = .04). Most existing programs were developed before 2000 and had a limited number of full-time equivalent staff, and few programs used a prospective audit-and-feedback structure. Many programs were not monitoring important end points associated with ASPs, including cost and number of antibiotic-days. The major barriers to implementation of an ASP were lack of resources, including funding, time, and personnel, noted by more than 50% of respondents. Regardless of the presence of an ASP, respondents perceived antibiotic resistance as a more significant problem nationally than at their local hospital (P < .001).

The prevalence of ASPs in pediatrics is limited, and opportunities exist to improve current programs.

To investigate the annual rate of tuberculosis (TB) infection among newly employed nurses using both tuberculin skin test (TST) and QuantiFERON-TB Gold (QFT-G; Cellestis Limited) assay.

A prospective cohort study involving newly employed nurses.

A tertiary care university hospital in South Korea.

All participants (n = 196) were tested with the TST and QFT-G assay at baseline. After 1 year, the TST and QFT-G assay were reperformed for subjects who had negative TST results at baseline and for all subjects, respectively.

The baseline TST and QFT-G assays were positive for 101 subjects (51.5%) and 28 subjects (14.3%), respectively; 22 subjects (11.2%) had positive results of both tests. Although the overall between-test agreement was 54.9% (κ = 0.151 [95% confidence interval, 0.047–0.245]), agreement improved to 78.5% (κ = 0.462 [95% confidence interval, 0.007–0.917]) for subjects who had not received bacille Calmette-Guérin vaccination. After 1 year, the TST yielded positive results for 16 (21.3%) of 75 nurses with negative baseline results, and the QFT-G assay yielded positive results for 21 (14.4%) of 146 subjects with negative baseline Results. Collectively, 5 subjects (3.0%) experienced conversion to positive results with both tests, and 32 subjects (18.9%) experienced conversion to positive results with one of the tests. Neither the employing hospital department nor exposure to patients with TB affected test conversion status.

The poor overall agreement between TST and QFT-G results may have been caused by the confounding effect of bacille Calmette-Guérin vaccination. The annual risk of TB infection among newly employed nurses was at least 3% on the basis of results of both the TST and QFT-G test. Stricter preventive strategies against TB spread should be implemented in our hospital.