Keith F. Woeltje

Mandatory Influenza Vaccination of Health Care Workers: Translating Policy to Practice

BACKGROUND Influenza vaccination of health care workers has been recommended since 1984. Multiple strategies to enhance vaccination rates have been suggested, but national rates have remained low. METHODS BJC HealthCare is a large Midwestern health care organization with approximately 26,000 employees. Because organizational vaccination rates remained below target levels, influenza vaccination was made a condition of employment for all employees in 2008. Medical or religious exemptions could be requested. Predetermined medical contraindications include hypersensitivity to eggs, prior hypersensitivity reaction to influenza vaccine, and history of Guillan-Barré syndrome. Medical exemption requests were reviewed by occupational health nurses and their medical directors. Employees who were neither vaccinated nor exempted by 15 December 2008 were not scheduled for work. Employees still not vaccinated or exempt by 15 January 2009 were terminated. RESULTS Overall, 25,561 (98.4%) of 25,980 active employees were vaccinated. Ninety employees (0.3%) received religious exemptions, and 321 (1.2%) received medical exemptions. Eight employees (0.03%) were not vaccinated or exempted. Reasons for medical exemption included allergy to eggs (107 [33%]), prior allergic reaction or allergy to other vaccine component (83 [26%]), history of Guillan-Barré syndrome (15 [5%]), and other (116 [36%]), including 14 because of pregnancy. Many requests reflected misinformation about the vaccine. CONCLUSIONS A mandatory influenza vaccination campaign successfully increased vaccination rates. Fewer employees sought medical or religious exemptions than had signed declination statements during the previous year. A standardized medical exemption request form would simplify the request and review process for employees, their physicians, and occupational health and will be used next year.

Quality of traditional surveillance for public reporting of nosocomial bloodstream infection rates.

CONTEXT Central line-associated bloodstream infection (BSI) rates, determined by infection preventionists using the Centers for Disease Control and Prevention (CDC) surveillance definitions, are increasingly published to compare the quality of patient care delivered by hospitals. However, such comparisons are valid only if surveillance is performed consistently across institutions. OBJECTIVE To assess institutional variation in performance of traditional central line-associated BSI surveillance. DESIGN, SETTING, AND PARTICIPANTS We performed a retrospective cohort study of 20 intensive care units among 4 medical centers (2004-2007). Unit-specific central line-associated BSI rates were calculated for 12-month periods. Infection preventionists, blinded to study participation, performed routine prospective surveillance using CDC definitions. A computer algorithm reference standard was applied retrospectively using criteria that adapted the same CDC surveillance definitions. MAIN OUTCOME MEASURES Correlation of central line-associated BSI rates as determined by infection preventionist vs the computer algorithm reference standard. Variation in performance was assessed by testing for institution-dependent heterogeneity in a linear regression model. RESULTS Forty-one unit-periods among 20 intensive care units were analyzed, representing 241,518 patient-days and 165,963 central line-days. The median infection preventionist and computer algorithm central line-associated BSI rates were 3.3 (interquartile range [IQR], 2.0-4.5) and 9.0 (IQR, 6.3-11.3) infections per 1000 central line-days, respectively. Overall correlation between computer algorithm and infection preventionist rates was weak (ρ = 0.34), and when stratified by medical center, point estimates for institution-specific correlations ranged widely: medical center A: 0.83; 95% confidence interval (CI), 0.05 to 0.98; P = .04; medical center B: 0.76; 95% CI, 0.32 to 0.93; P = .003; medical center C: 0.50, 95% CI, -0.11 to 0.83; P = .10; and medical center D: 0.10; 95% CI -0.53 to 0.66; P = .77. Regression modeling demonstrated significant heterogeneity among medical centers in the relationship between computer algorithm and expected infection preventionist rates (P < .001). The medical center that had the lowest rate by traditional surveillance (2.4 infections per 1000 central line-days) had the highest rate by computer algorithm (12.6 infections per 1000 central line-days). CONCLUSIONS Institutional variability of infection preventionist rates relative to a computer algorithm reference standard suggests that there is significant variation in the application of standard central line-associated BSI surveillance definitions across medical centers. Variation in central line-associated BSI surveillance practice may complicate interinstitutional comparisons of publicly reported central line-associated BSI rates.

Tuberculosis infection and anergy in hemodialysis patients

Patients on hemodialysis are at increased risk for developing active tuberculosis (TB) after primary infection. Although this increased risk is well documented, the prevalence of TB infection, as indicated by a positive tuberculin skin test (TST), is not well described. End-stage renal disease is also known to be a risk factor for skin test anergy, but the rate of anergy in hemodialysis patients is unclear. We sought to identify rates of anergy and TST positivity in patients at four hemodialysis units in St Louis, Missouri, from June 1996 through August 1996. Data obtained from patients and medical records included age, years on hemodialysis, medical history, and basic laboratory data. Patients without a history of TB or a positive TST had a TST with Tubersol, as well as candida and tetanus controls, placed by the Mantoux method. Tests were read 48 hours later. Of the patients enrolled at these units, 307 of 331 (93%) were evaluated. Patients had a mean age of 58 years (range, 19 to 91 years) and had been on hemodialysis for a mean of 3.7 years (range, 1 week to 18.7 years). Blacks made up 81% of the population. A history of a positive TST was obtained from 24 patients (8%), and an additional seven (2%) had a history of active TB. Of the 276 patients tested, 93 did not respond to either control antigen, but five of these patients had a positive TST, leaving 88 (32%) anergic. Anergy was related to age, immunosuppressive drug use, and the reagents used, but not to urea reduction ratio. Positive TSTs were found in 17 of 188 of nonanergic patients (9%) (6% of all tested patients). Overall, 48 of 307 patients (16%) had a positive TST or history of TB. TB or a positive TST was associated with liver disease and peptic ulcer disease, but not socioeconomic status. All 17 newly identified TST-positive patients received chest radiographs. No new cases of active TB were found. Only two of 17 of these patients (12%) were started on isoniazid (INH) prophylaxis. We identified high rates of TST positivity and anergy in the hemodialysis patients tested. Hemodialysis patients should receive regular TST screening, and INH prophylaxis needs to be more strongly encouraged. Studies are ongoing to define the rate of TST conversion over time.

Endotracheal tube biofilm inoculation of oral flora and subsequent colonization of opportunistic pathogens.

Endotracheal (ET) tubes accumulate a biofilm during use, which can harbor potentially pathogenic microorganisms. The enrichment of pathogenic strains in the biofilm may lead to ventilator-associated pneumonia (VAP) with an increased morbidity rate in intensive care units. We used quantitative PCR (qPCR) and gene surveys targeting 16S rRNA genes to quantify and identify the bacterial community to detect fastidious/nonculturable organisms present among extubated ET tubes. We collected eight ET tubes with intubation periods between 12 h and 23 d from different patients in a surgical and a medical intensive care unit. Our qPCR data showed that ET tubes were colonized within 24 h. However, the variation between patients was too high to find a positive correlation between the bacterial load and intubation period. We obtained 1263 near full-length 16S rRNA gene sequences from the diverse bacterial communities. Over 70% of these sequences were associated with genera of typical oral flora, while only 6% were associated with gastrointestinal flora. The most common genus identified was Streptococcus (348/1263), followed by Prevotella (179/1263), and Neisseria (143/1263) with the highest relative concentrations for ET tubes with short intubation periods, indicating oral inoculation of the ET tubes. Our study also shows that even though potentially pathogenic bacteria existed in ET tube biofilms within 24 h of intubation, a longer intubation period increases the opportunity for these organisms to proliferate. In the ET tube that was in place for 23 d, 95% of the sequences belonged to Pseudomonas aeruginosa, which is a bacterial pathogen that is known to out compete commensal bacteria in biofilms, especially during periods of antibiotic treatment. Harboring such pathogens in ET biofilms may increase the chance of VAP, and should be aggressively monitored and prevented.

Attributable costs of enterococcal bloodstream infections in a nonsurgical hospital cohort.

BACKGROUND Vancomycin-resistant Enterococcus (VRE) bloodstream infections (BSIs) are associated with increased morbidity and mortality. OBJECTIVE To determine the hospital costs and length of stay attributable to VRE BSI and vancomycin-sensitive Enterococcus (VSE) BSI and the independent effect of vancomycin resistance on hospital costs. METHODS A retrospective cohort study was conducted of 21,154 nonsurgical patients admitted to an academic medical center during the period from 2002 through 2003. Using administrative data, attributable hospital costs (adjusted for inflation to 2007 US dollars) and length of stay were estimated with multivariate generalized least-squares (GLS) models and propensity score-matched pairs. RESULTS The cohort included 94 patients with VRE BSI and 182 patients with VSE BSI. After adjustment for demographics, comorbidities, procedures, nonenterococcal BSI, and early mortality, the costs attributable to VRE BSI were

Infection prevention in the intensive care unit.

4,479 (95% confidence interval [CI],

Automated Surveillance for Central Line-Associated Bloodstream Infection in Intensive Care Units

3,500-

Electronic surveillance for healthcare-associated central line-associated bloodstream infections outside the intensive care unit

5,732) in the standard GLS model and

Formulation of a model for automating infection surveillance: algorithmic detection of central-line associated bloodstream infection

4,036 (95% CI,

Data Requirements for Electronic Surveillance of Healthcare-Associated Infections

3,170-