Aspergillus fumigatus is a major pathogen causing nosocomial infections. Hospital outbreaks of invasive aspergillosis have been associated with the renovation and construction of buildings. Building construction work for fire safety upgrading was undertaken during a 16-week period in 2001 at Box Hill Hospital. This study was designed to examine the effect of construction on invasive aspergillosis when using standard and additional protective measures.

Baseline air sampling was conducted in 18 areas. The validity of the air sampling was assessed by comparing the ability of two air samplers to detect Aspergillus conidia. Surveillance of nosocomial Aspergillus infection was conducted by reviewing the records of patients with a sputum culture positive for Aspergillus and those prescribed amphotericin or itraconazole for the period of construction activity and the same period the previous year.

Aspergillus was isolated infrequently and there was no statistically significant difference in the levels of viable pathogenic fungi between areas where construction work was undertaken and areas where it was not undertaken. A moderate agreement was observed between the two air samplers (kappa = 0.4; P < .05). There was no difference in the incidence of invasive aspergillosis between 2000 and 2001 (incidence density ratio, 1.2; 95% confidence interval, 0.3 to 4.1).

The influence of construction work performed with protective measures needs to be examined in an environment with higher levels of airborne fungi to confirm the findings of this study (Infect Control Hosp Epidemiol 2003;24:472-476).

Infliximab is a chimeric monoclonal antibody against tumor necrosis factor (TNF)-alpha, used for the treatment of Crohn's disease and rheumatoid arthritis. Recently, an increased risk of infection due to Mycobacterium tuberculosis and rare cases of invasive fungal disease have been reported following infliximab therapy.

A 73-year-old woman with chronic rheumatoid arthritis who had been treated with methotrexate, leflunomide, and prednisone was given the first of three doses of infliximab in June 2001. In July 2001, she presented with cough, and in August, she had a right upper lobe infiltrate that was treated with levofloxacin without improvement. In October, the patient had right upper and middle lobe infiltrates on a chest x-ray and computed tomography scan. At bronchoscopy, an endobronchial mass was biopsied, which demonstrated Aspergillus fumigatus. Our patient had frequently accompanied her daughter on visits to another medical center following a stem cell transplant, where her daughter was instructed to wear a mask during all visits because of extensive building construction. We postulate that our patient may have acquired pulmonary aspergillosis during this period. Literature reviews on granulomatous diseases following infliximab therapy and hospital-acquired aspergillosis are presented.

The temporal relationship between the administration of infliximab and A. fumigatus infection in this patient suggests a causal relationship and possible healthcare-associated acquisition. These data underscore the importance of both patient and family education on prevention strategies when potent immune-modulating medications such as infliximab have been prescribed (Infect Control Hosp Epidemiol 2003;24:477-482)

To evaluate the airborne viable bacterial concentrations generated during sputum induction and their reduction with exhaust ventilation, ultraviolet germicidal irradiation (UVGI), or both.

Exhaust ventilation, upper air UVGI lights, and a portable UVGI unit were operated independently or in combination while and after sputum induction was performed for 58 patients suspected of having active tuberculosis. Viable airborne bacteria were sampled with volumetric air samplers, grown on blood agar, and identified with standard techniques.

During and immediately after sputum induction, concentrations of airborne bacteria, particularly respiratory tract or oropharyngeal organisms, increased rapidly, regardless of environmental conditions. The subsequent rate of reduction of airborne bacteria was most rapid with the portable UVGI unit, followed by upper air UVGI with air mixing. Exhaust ventilation achieved high air changes per hour, but efficacy in reducing airborne bacterial concentrations was low. However, the continuous entrainment of bacteria-laden air from the hallway outside may have resulted in underestimation. The efficacy of a wall-mounted upper air UVGI fixture was significantly less if there was no air mixing. The irradiation from this fixture was of adequate germicidal intensity only in a narrow horizontal plane 2.5 m above the floor.

Sputum induction was associated with a rapid and substantial increase in airborne bacteria despite the use of exhaust ventilation providing more than 30 air changes per hour, and the adjunct use of UVGI. This emphasizes that health-care workers involved in similar cough-inducing procedures performed for patients with suspected tuberculosis must wear appropriate personal respirators (Infect Control Hosp Epidemiol 2003;24:483-489)

To investigate the molecular epidemiology of systemic nosocomial infections caused by Enterobacter cloacae.

Neonatal intensive care unit (NICU) of a tertiary-care university hospital.

Forty-two high-risk neonates with systemic infections caused by E. cloacae.

From 1995 to 1997, the variables associated with death in these patients were evaluated. The molecular epidemiology of the strains responsible for the systemic infections, and 14 unrelated strains, was studied using plasmid analysis and pulsed-field gel electrophoresis (PFGE).

The overall mortality rate for infection caused by E. cloacae was 34%, whereas the crude mortality rate during the study period was 8.12% (P < .001). Gestational age (preterm neonates) and birth weight (small for gestational age) were not associated with a higher risk of death. Insertion of a venous catheter by dissection of a peripheral vein was the only invasive procedure related to death (P = .016) in this study. A molecular analysis showed that three outbreaks, each occurring in a different year, were caused by strains with distinctive DNA profiles. Only one outbreak was identified by the infection control service, in the NICU. Plasmid analysis and PFGE showed similar ability to discriminate control strains from the E. cloacae strains isolated from the neonates.

Systemic infections caused by E. cloacae in our NICU were associated with a high mortality rate and occurred as small, unrecognized outbreaks. These results may not be generalizable because the data were from a single center (Infect Control Hosp Epidemiol 2003;24:490-494).

To investigate the clinical, microbiological, and epidemiologic features of three outbreaks caused by Klebsiella during 3 years.

Neonatal intensive care unit of a university hospital.

Thirty affected neonates.

Data were collected through chart reviews and conversations with physicians. Screening samples were obtained from the staff, the neonates, and the environment. Antibiogram typing and arbitrarily primed polymerase chain reaction-based fingerprinting were used to type the strains.

The first outbreak had 13 K. pneumoniae strains isolated. The second outbreak had 10 K. oxytoca strains isolated. The third outbreak had 20 K. pneumoniae strains isolated. More than half of the patients had low birth weights, were premature, and underwent mechanical ventilation and intravenous catheterization. Approximately three-fourths of the patients died. The isolates tested were completely susceptible to meropenem, cefoxitin, and ciprofloxacin and were resistant to cephalothin. More than half of these strains were resistant to many beta-lactam antibiotics, amikacin, and trimethoprim/sul-famethoxazole. Typing procedures yielded 3 antibiotypes and 3 genotypes among the isolates of the first outbreak, 3 antibiotypes with 1 subtype and 2 genotypes with 1 subtype in the second outbreak, and 2 antibiotypes and 2 genotypes in the third outbreak.

Klebsiella outbreaks mainly affected premature neonates with intravenous catheters, mechanical ventilation, or both. The high mortality rate (76.7%) was notable. Resistance to multiple antibiotics, but mainly to broad-spectrum beta-lactam antibiotics, was observed, particularly in K. pneumoniae isolates. Molecular typing indicated that the three outbreaks were not related to one other (Infect Control Hosp Epidemiol 2003;24:495-500).

The German Nosocomial Infection Surveillance System (KISS) began in 1997 as a nationwide surveillance project for voluntary registration of nosocomial infections in intensive care units (ICUs). This study investigates trends in the rates of central venous catheter (CVC)–associated primary bloodstream infections (BSIs) in ICUs since participation in KISS.

Eighty-four ICUs that had participated in KISS for at least 24 months were considered for more detailed analysis. Monthly rates of primary BSI for the 84 ICUs were pooled for the 24 months. The best model for describing the curve of reduction was sought. Additionally, incidence densities were compared using the z test.

For the 212 ICUs participating, a relative 25.7% decrease (from 2.1 to 1.6 primary BSIs per 1,000 CVC-days) was observed from January 1997 to June 2001. The 84 ICUs that participated in KISS for a minimum of 24 months accumulated 552,359 patient-days and 404,897 CVC-days during their 24 months. A linear regression model was selected to explain the curve of primary BSI reduction in the 84 ICUs. It showed a decrease from 2.1 to 1.5 primary BSIs per 1,000 CVC-days, meaning an overall relative reduction of 28.6% during the 2-year observation period. These results were significant (Student's t test for the monthly reduction coefficient; P = .04). The reduction of primary BSIs was shown for both clinical sepsis and laboratory-confirmed, CVC-associated primary BSIs.

Performing surveillance with KISS was associated with a reduction of the rates of CVC-associated primary BSIs in ICU patients (Infect Control Hosp Epidemiol 2003;24:501-505).

To evaluate the long-term efficacy of urinary Foley catheters (latex and silicone) impregnated with (1) chlorhexidine and silver sulfadiazine (CXS) and (2) chlorhexidine, silver sulfadiazine, and triclosan (CXST) in inhibiting extra-luminal bacterial adherence and to compare their efficacy with that of silver hydrogel latex (SH) and nitrofurazone-treated silicone (NF) catheters.

The antimicrobial spectrum of these catheters was evaluated using a zone of inhibition assay. A novel in vitro urinary tract model was developed to study the potential in vivo efficacy of antimicrobial catheters in preventing extraluminal bacterial colonization. The “meatus” was inoculated daily with Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Enterococcus faecalis, Pseudomonas aeruginosa, and Candida albicans. The “bladder” portion of the model was cultured daily to determine bacterial growth.

Both CXS and CXST catheters had a broader antimicrobial spectrum than SH and NF catheters. In the in vitro model, CXST latex and silicone catheters exhibited significantly better efficacy (3 to 25 days) against uropathogens, compared with CXS (1 to 14 days) and control (0 to 5 days) catheters (P = .01). CXST latex catheters exhibited significantly longer protection against Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, and Pseudomonas aeruginosa, compared with SH catheters (P = .01). CXST silicone catheters resisted colonization with Staphylococcus aureus and Staphylococcus epidermidis for a significantly longer period (23 to 24 days) than did NF catheters (9 to 11 days) (P = .01).

Catheters impregnated with synergistic combinations of chlorhexidine, silver sulfadiazine, and triclosan exhibited broad-spectrum, long-term resistance against microbial colonization on their outer surfaces (Infect Control Hosp Epidemiol 2003;24:506-513)

To investigate and control an outbreak of epidemic keratoconjunctivitis (EKC) occurring in a neonatal intensive care unit (NICU) and to determine signs specific for EKC in newborns.

Outbreak investigation and case–control study.

NICU of a 1,600-bed university hospital in Heidelberg, Germany.

Case-patients were defined as individuals who had adenoviral antigen detected by ELISA or by PCR from conjunctival swabs or who had clinical signs of conjunctivitis. Twelve newborns from the NICU who had EKC between October and November 1998 were compared with 11 who had bacterial conjunctivitis.

Control measures included cohorting patients in contact isolation, using gloves and gowns for patient care, and using a hand rub and disinfectants with virucidal activity.

Thirteen patients, 6 healthcare workers, and 11 relatives of the patients had EKC, according to our case definition. Case-patients were more likely than control-patients to develop lacrimal swelling (P < .001), eye redness (P = .004), and lacrimation (P = .037) involving both eyes (P = .002). Prior examination by an ophthalmologist was a significant risk factor for EKC (P = .004). For diagnosis or treatment of retinopathy, premature newborns were seen by an ophthalmologist from a nearby eye care center where an EKC outbreak was ongoing. No new cases were diagnosed more than 10 days after the implementation of control measures.

In newborns, lacrimal swelling, eye redness, and lacrimation in both eyes should evoke suspicion of EKC. Ophthalmologists who have had contact with known EKC cases should use antiseptics and disinfectants with virucidal activity before contact with newborns or abstain from examining newborns (Infect Control Hosp Epidemiol 2003;24:514-519)

To investigate the relationship between hygienic measures reported for the prevention of hospital-acquired diarrhea and incidence rates of hospital-acquired diarrhea.

A survey of hospital-acquired diarrhea was conducted between January 1 and March 31, 1999. Multivariate analysis of reported measures of hygiene according to the observed incidence rates of hospital-acquired diarrhea was performed.

Thirty-one pediatric or neonatal wards located in hospitals in the southeast of France, selected as a convenience sample of wards volunteering to participate.

A total of 6,726 children younger than 5 years.

The overall incidence rate of hospital-acquired diarrhea was 3.6%. Rotavirus was responsible for 69% of the cases of hospital-acquired diarrhea. Among the hygienic measures reported by the wards for preventing hospital-acquired diarrhea were using a single room or cohorting (77.4%), washing hands (83.9%), wearing gowns (80.6%), and wearing disposable single-use gloves for diapering a patient (51.6%). By multivariate analysis, the variables statistically associated with a lower incidence of hospital-acquired diarrhea were restricting the patient's mobility outside his or her room, keeping the patient's door closed, and having fewer than 20 beds in the ward, with adjusted odds ratios of 0.34 (95% confidence interval [CL95], 0.18 to 0.65), 0.33 (CI95, 0.23 to 0.47), and 0.42 (CI95, 0.30 to 0.60), respectively.

Simple preventive measures can decrease the rate of hospital-acquired diarrhea in pediatric wards (Infect Control Hosp Epidemiol 2003;24:520-525)

To increase the proportion of inpatients vaccinated against pneumococcal infection.

Pre- and post-intervention study.

University medical center–affiliated, suburban community teaching hospital.

Unvaccinated inpatients 65 years and older and those 2 to 64 years old who had chronic medical conditions predisposing them to invasive pneumococcal infection.

The nursing staff screened newly admitted patients for eligibility based on age, diagnosis, or medications from a computer-generated admissions list and placed a pre-printed order form for the pneumococcal polysaccharide vaccine (PPV) on the charts of eligible patients. Following the physician's order, the nursing staff administered the PPV and recorded it. Ongoing quality improvements including admission vaccination screening and computer-based record keeping were initiated to identify unvaccinated eligible patients and track vaccination status.

Efforts resulted in rates of in-hospital vaccination ranging from 3.1% to 7.9% (mean, 5.2% ± 1.7% [standard deviation]) and significant improvements in the assessment of previous vaccination status, reaching 54% of eligible patients after 1 year. Ascertainment of a previous vaccination increased significantly following the initiation of the use of admission forms that specifically assessed vaccination status and a system to permanently record vaccination status in an electronic medical record (P < .05).

Concerted efforts using electronic medical records significantly improved the assessment and documentation of inpatient vaccination status. Greater improvement of the rates of in-hospital vaccination will require healthcare system–wide efforts such as a standing order policy for vaccinating all eligible patients. Standing orders for inpatient immunization supported by effective assessment and tracking systems have the potential to raise vaccination rates to the goals of Healthy People 2010 (Infect Control Hosp Epidemiol 2003;24:526-531)