To compare the epidemiology and genetic relatedness of Candida tropicalis isolates causing bloodstream infection (BSI) in two hospitals.

Two tertiary-care hospitals in Korea.

A retrospective molecular epidemiologic analysis using pulsed-field gel electrophoresis (PFGE) was performed with 49 C. tropicalis isolates from sporadic cases of BSI. The isolates were collected from 27 patients at Chonnam National University Hospital (CUH) during a 6-year period and 22 patients at Asan Medical Center (AMC) during a 2-year period.

Based on the PFGE patterns, the average similarity value (SAB) for the 27 isolates from CUH was 0.84 ± 0.08, which was significantly higher than that for the 22 isolates from AMC (0.78 ± 0.06; P < .001). Of the 49 strains from patients at the 2 hospitals, 9 isolates were placed into 3 subtypes with SAB values of 1.0, which indicated that they were identical. All 9 of these strains were isolated from CUH patients, and each type strain was isolated sporadically during a period ranging from 4 months to 3 years. On comparison of the clinical characteristics of the patients of the 2 hospitals, the CUH strains were isolated more frequently from non-neutropenic patients and patients with central venous catheter–related fungemia; cases from CUH had a better outcome than those from AMC (P < .05).

These data show that the clinical and epidemiologic characteristics of C. tropicalis fungemia may differ markedly among hospitals and that some cases of C. tropicalis fungemia may be caused by endemic strains within a hospital.

To investigate the clinical features and the epidemiology of Acinetobacter baumannii in Spanish hospitals.

Prospective multicenter cohort study.

Twenty-seven general hospitals and one paraplegic center in Spain.

All cases of A. baumannii colonization or infection detected by clinical samples during November 2000 were included. Isolates were identified using phenotypic and genotypic methods. The molecular relatedness of the isolates was assessed by pulsed-field gel electrophoresis.

Twenty-five (89%) of the hospitals had 221 cases (pooled rate in general hospitals, 0.39 case per 1,000 patient-days; range, 0 to 1.17). The rate was highest in intensive care units (ICUs). Only 3 cases were pediatric. The mean age of the patients in the general hospitals was 63 years; 69% had a chronic underlying disease and 80% had previously received antimicrobial treatment. Fifty-three percent of the patients had an infection (respiratory tract, 51%; surgical site, 16%; and urinary tract, 11%). Crude mortality was higher in infected than in colonized patients (27% vs 10%; relative risk, 1.56; 95% confidence interval, 1.2 to 2.0; P = .003). Molecular analysis disclosed 79 different clones. In most hospitals, a predominant epidemic clone coexisted with other sporadic clones. Imipenem resistance was present in 39% of the hospitals.

A. baumannii was present in most participating Spanish hospitals (particularly in ICUs) with different rates among them. The organisms mainly affected predisposed patients; half of them were only colonized. Epidemic and sporadic clones coexisted in many centers.

To examine whether implementation of safety-engineered devices in 2001 had an effect on rates of percutaneous injury (PI) reported by HCWs.

Before-and-after intervention trial comparing 3-year preintervention (1998–2001) and 2-year postintervention (2001–2002) periods. PI data from anonymous, self-administered surveys were prospectively entered into CDC NaSH software.

A 427-bed, tertiary-care hospital in Manhattan.

HCWs who attended state-mandated training sessions and completed the survey (1,132 preintervention; 821 postintervention).

Implementation of a “safer-needle system” composed of various safety-engineered devices for needle-safe TV delivery-insertion, blood collection, and intramuscular-subcutaneous injection.

Preintervention, the overall annual rate of PIs self-reported on the survey was 36.5 per 100 respondents, compared with 13.9 per 100 respondents postintervention (P < .01). The annual rate of formally reported PIs decreased from 8.3 to 3.1 per 100 respondents (P < .01). Report rates varied by occupational group (P ≤ .02). The overall rate did not change between study periods (22.7% to 22.3%), although reporting improved among nurses (23.6% to 44.4%, P = .03) and worsened among building services staff (90.5% to 50%, P = .03). HCWs with greater numbers of Pis self-reported on the survey were less likely to formally report injuries (P < .01). The two most common reasons for nonreport (ie, thought injury was low risk or believed patient was low risk for blood-borne disease) did not vary from preintervention to postintervention.

Safety-engineered device implementation decreased rates of Pis formally reported and self-reported on the survey. However, this intervention, with concomitant intensive education, had varying effects on reporting behavior by occupation and a minimal effect on overall reporting rates.

The practice of safety measures by the food service staff in hospitals is necessary for the prevention of food-borne outbreaks. Hospitalized patients are more vulnerable to potential hazards, and neglecting these principles can lead to increased morbidity and mortality.

We assessed the knowledge, attitudes, and practices of food service staff regarding food hygiene in government and private hospitals in Shiraz, Iran. Two questionnaires were designed, one for food service staff and the ofher for supervisors. Thirty-one hospitals were approached, and the response rate was 99.5%. Four models were developed regarding knowledge, attitudes, and practices, and a multiple logistic regression analysis was performed. Comparison among the government and private hospitals was done.

This study showed that personnel had little knowledge regarding the pathogens that cause food-borne diseases and the correct temperature for the storage of hot or cold ready-to-eat foods. Older personnel had better attitudes and practices. Females practiced safety measures less often than did males. Personnel working in hospitals with fewer than 300 beds also had better practices. Most of the personnel had positive attitudes, but disparity between attitude and practice was noted.

There is a dire need for education and increased awareness among food service staff regarding safe food handling practices.

To describe the epidemiology of endemic multidrug-resistant Pseudomonas aeruginosa colonizations and infections in critically ill patients.

Prospective study on bacterial strain typing and retrospective cohort study of charts of patients in the intensive care unit (ICU).

Fifty-three patients with P. aeruginosa isolated from clinical cultures in 2001 were selected, divided into those with P. aeruginosa in vitro resistant to at least two classes of antibiotics (multidrug-resistant, n = 18) and those susceptible to all or resistant to only one antibiotic (susceptible, n = 35).

Risk factors for multidrug-resistant P. aeruginosa included maxillary sinusitis, long-dwelling central venous catheters, prolonged use of certain antibiotics, a high lung injury score, and prolonged mechanical ventilation and duration of stay. The frequency of colonization (approximately 50%) versus infection (ie, ventilator-associated pneumonia) did not differ between the groups. On amplified fragment-length polymorphism analysis, 64% of the multidrug-resistant strains had been potentially transmitted via cross-colonization and 36% had probably originated endogenously. ICU mortality was 22% in the multidrug-resistant group and 23% in the susceptible group, although the duration of mechanical ventilation was longer in the former.

Patients with sinusitis who stayed in the ICU longer, were ventilated longer because of acute lung injury, received antibiotics for longer durations, and had long-dwelling central venous catheters ran an elevated risk of acquiring multidrug-resistant P. aeruginosa. These patients did not have a higher mortality than patients with susceptible P. aeruginosa. Prevention of the emergence of multidrug-resistant strains requires changes in infection control measures and antibiotic policies in our ICU.

Antibiotic-associated disruption of the indigenous intestinal microflora may persist beyond the treatment period. Although piperacillin/tazobactam inhibits the establishment of vancomycin-resistant Enterococcus (VRE) stool colonization in mice during treatment, we hypothesized that this agent and other anti-anaerobic antibiotics would increase susceptibility to colonization during the period of recovery of the intestinal microflora.

Mice received 104 colony-forming units of vancomycin-resistant E. faecium by orogastric inoculation 2, 5, or 10 days after completing 5 days of subcutaneous antibiotic treatment, or both during and 2 days after the completion of treatment. Denaturing gradient gel electrophoresis (DGGE) was performed to assess changes in the intestinal microflora.

Anti-anaerobic antibiotics (ie, piperacillin/tazobactam, cefoxitin, and clindamycin) caused significant disruption of the indigenous microflora (mean DGGE similarity indices ≤ 27% in comparison with saline controls) and promoted the establishment of high-density colonization when VRE was inoculated 2 or 5, but not 10, days following treatment (P < .001). Piperacillin/tazobactam exhibited a biphasic effect on the establishment of colonization (ie, inhibition when exposed to VRE during treatment and promotion when exposed to VRE after discontinuation of treatment), resulting in greater overall promotion of colonization than did agents with minimal anti-anaerobic activity (ie, levofloxacin, cefepime, and aztreonam) when VRE was inoculated both during and 2 days after treatment (P< .001).

Patients receiving anti-anaerobic antibiotics, including piperacillin/tazobactam, may be susceptible to the establishment of high-density VRE colonization during the period of recovery of the anaerobic microflora.

Despite the novelties in operating room ventilation, airborne bacteria remain an important source of surgical wound contamination. An ultraclean airflow from the ceiling downward may convey airborne particles from the surgical team into the wound, thus increasing the risk of infection. Therefore, similar ventilation from the wound upward should be considered. We investigated the effect of wound ventilation on the concentration of airborne particles in a wound model during simulated surgery.

Randomized experimental study simulating surgery with a wound cavity model.

An operating room of a university hospital ventilated with ultraclean air directed downward.

Particles 5 um and larger were counted with and without a 5-cm deep cavity and with and with-out the insufflation of ultraclean air.

With the surgeon standing upright, no airborne particles could be detected in the wound model. In contrast, during simulated operations, the median number of particles per 0.1 cu ft reached 18 (25th and 75th percentiles, 12 and 22.25) in the model with a cavity and 15.5 (25th and 75th percentiles, 14 and 21.5) without. With a cavity, wound ventilation markedly reduced the median number of particles to 1 (range, 0 to 1.25; P< .001).

To protect a surgical wound against direct airborne contamination, air should be directed away from the wound rather than toward it. This study provides supportive evidence to earlier studies that operating room ventilation with ultraclean air is imperfect during surgical activity and that wound ventilation may be a simple complement. Further clinical trials are needed.

To examine organizational factors and occupational characteristics associated with adherence to occupational safety guidelines recommending never recapping needles.

Mail surveys were conducted with healthcare workers (HCWs) and infection control professionals (ICPs).

The surveys were conducted at all non-federal general hospitals in Iowa, except one tertiary-care hospital. Survey data were linked to annual survey data of the American Hospital Association (AHA).

HCWs were sampled from statewide rosters of physicians, nurses, and laboratory workers in Iowa. Eligible HCWs worked in a setting and position in which they were likely to routinely handle needles. ICPs at all hospitals in the state were surveyed.

Ninety-nine ICPs responded (79% response rate). AHA data were available for all variables from 84 (85%) of the hospitals. Analyses were based on 1,454 HCWs who identified one of these hospitals as their primary hospital (70% response rate). Analyses were conducted using multiple logistic regression. Positive predictors of consistent adherence included infection control personnel hours per full-time–equivalent employee (odds ratio [OR], 1.03), frequency of standard precautions education (OR, 1.11), facilities providing personal protective equipment (OR, 1.82), facilities using needleless intravenous systems (OR, 1.42), and management support for safety (OR, 1.05). Negative predictors were use of “blood and body fluid precautions” isolation category (OR, 0.74) and increased job demands (OR, 0.90).

Healthcare organizations can improve staff safety by investing wisely in educational programs regarding approaches to minimize these risks, providing protective equipment, and eliminating the use of blood and body fluid precautions as an isolation policy.

To evaluate the dynamics of bacterial contamination of healthcare workers' (HCWs) hands during neonatal care.

The 20-bed neonatal unit of a large acute care teaching hospital in Geneva, Switzerland.

Structured observation sessions were conducted. A sequence of care began when the HCW performed hand hygiene and ended when the activity changed or hand hygiene was performed again. Alcohol-based handrub was the standard procedure for hand hygiene. An imprint of the five fingertips of the dominant hand was obtained before and after hand hygiene and at the end of a sequence of care. Regression methods were used to model the final bacterial count according to the type and duration of care and the use of gloves.

One hundred forty-nine sequences of care were observed. Commensal skin flora comprised 72.4% of all culture-positive specimens (n = 360). Other microorganisms identified were Enterobacteriaceae (n = 55, 13.8%); Staphylococcus aureus (n = 10, 2.5%); and fungi (n = 7,1.8%). Skin contact, respiratory care, and diaper change were independently associated with an increased bacterial count; the use of gloves did not fully protect HCWs' hands from bacterial contamination.

These data confirm that hands become progressively contaminated with commensal flora and potential pathogens during neonatal care, and identify activities at higher risk for hand contamination. They also reinforce the need for hand hygiene after a sequence of care, before starting a different task, and after glove removal.

To review the evidence regarding the effects of interventions to improve hospital design and construction on the occurrence of nosocomial infections.

Systematic review of experimental and non-experimental, architectural intervention studies in intensive care units (ICUs), surgical departments, isolation units, and hospitals in general. The studies dated from 1975, and were in English, French, German, Italian, and Spanish. Regardless of format, the studies were identified through seven medical databases, reference lists, and expert consultation.

One hundred seventy-eight scientific articles were identified; however, none of these described a meta-analy-sis, systematic review, or randomized, controlled trial. Most of the articles were categorized at the lowest level of evidence (expert judgment or consensus statements). Only 17 described completed concurrent or historical cohort studies matching the inclusion criteria (ICUs, 9; surgical departments, 4; isolation units, 2; hospitals in generai, 2). The interventions generally included a move to other premises or renovation. However, in many studies, the staff-to-patient ratio was also improved. Some studies showed lower infection rates after intervention, but this finding cannot be generalized because of confounding and fre-quently small study populations.

The lack of stringent evidence linking hospital design and construction with the prevention of nosocomial infection is partly attributable to the multifactorial nature of these infections, and some improvement will be seen if basic conditions such as the availability of sufficient space, isolation capac-ity, and facilities for handwashing are met. However, to our knowledge, other factors, especially the improper hand hygiene of medical staff, have greater impact.

To assess the co-colonization rates of extended-spectrum beta-lactamase (ESBL)-producing bacteria and vancomycin-resistant Enterococcus (VRE) obtained on active surveillance cultures.

Prospective cohort study.

Medical and surgical intensive care units (ICUs) of a tertiary-care hospital.

Patients admitted between September 2001 and November 2002 to the medical and surgical ICUs at the University of Maryland Medical System had active surveillance perirectal cultures performed. Samples were concurrently processed for VRE and ESBL-producing bacteria.

Of 1,362 patients who had active surveillance cultures on admission, 136 (10%) were colonized with VRE. Among these, 15 (positive predictive value, 11%) were co-colonized with ESBL. Among the 1,226 who were VRE negative, 1,209 were also ESBL negative (negative predictive value, 99%). Among the 1,362 who had active surveillance cultures on admission, 32 (2%) were colonized with ESBL. Among these, 15 (47%) were co-colonized with VRE. Of the 32 patients colonized with ESBL, 10 (31%) had positive clinical cultures for ESBL on the same hospital admission. For these 10 patients, the surveillance cultures were positive an average of 2.7 days earlier than the clinical cultures.

Patients who are colonized with VRE can also be co-colonized with other antibiotic-resistant bacteria such as ESBL-producing bacteria. Our study is the first to measure co-colonization rates of VRE and ESBL-producing bacteria. Isolating VRE-colonized patients would isolate 47% of the ESBL-colonized patients without the need for further testing. Hence, active surveillance for VRE should also theoretically diminish the amount of patient-to-patient transmission of ESBL-producing bacteria.

To study clusters of infections caused by Serratia marcescens in a neonatal intensive care unit (NICU) and to determine risk factors for S. marcescens infection or colonization.

Genotyping of S. marcescens isolates was performed by pulsed-field gel electrophoresis (PFGE). A retrospective case-control study was conducted.

A tertiary-care pediatric hospital with a 16-bed NICU.

All neonates with at least one culture positive for S. marcescens in the NICU during December 1999 to July 2002. Case-patients (n = 11) treated in the NICU during December 1999 to February 2000 were included in the case-control study. Neonates treated in the NICU for at least 72 hours during the same period with cultures negative for S. marcescens were used as control-patients (n = 27).

S. marcescens was cultured from 19 neonates; 9 were infected and 10 were colonized. PFGE analysis identified three epidemic strains; each cluster consisted of identical isolates, except one isolate in the first cluster that was different. The risk factors identified were low birth weight, prematurity, prolonged respiratory therapy, prolonged use of antibiotics, and maternal infection prior to delivery. Overcrowding and understaffing were recorded simultaneously with the clusters.

PFGE analysis showed three independent clusters. Several factors contributed to spread of the epidemic strains: (1) there were many severely premature and susceptible neonates, (2) the NICU was overcrowded during the clusters, and (3) transmission was likely to occur via the hands of staff. Cohorting and improvement of routine infection control measures led to the cessation of each cluster.

To investigate an outbreak of Candida parapsilosis bloodstream infections (BSIs) involving three patients admitted to a pediatric oncology unit between April and June 2002.

After the third case was documented, cultures were performed of the hands of all medical and paramedical staff members in the pediatric oncology unit and of environmental surfaces in the rooms occupied by the three patients. Electrophoretic karyotyping with pulsed-field gel electrophoresis and arbitrarily primed polymerase chain reaction were used to assess the genetic relatedness among C. parapsilosis isolates.

The three cases of C. parapsilosis BSI were diagnosed based on blood cultures performed during a 38-day period. Evidence of prior C. parapsilosis colonization of the gastrointestinal tract was present in only the first case. Each patient had an indwelling central venous catheter (CVC), which was promptly removed, and semiquantitative catheter tip cultures also revealed C. parapsilosis. None of the 30 environmental cultures performed was positive for C. parapsilosis, but the fungus was isolated from the hands of 6 of the 20 nurses tested. Both molecular typing methods revealed identical DNA fingerprinting patterns for all 13 patient isolates (7 from blood, 3 from CVC tips, and 3 from the gastrointestinal tract) and for 5 of the 6 recovered from the nurses' hands.

These findings suggest the possibility of cross-infection with a single C. parapsilosis strain that was transmitted (probably during CVC dressing changes) by nurses whose hands were colonized with it. The role of previous gastrointestinal colonization in the first case cannot be excluded.