To determine hospital-related risk factors for surgical-site infection (SSI) following hip arthroplasty.

Prospective, multicenter cohort study based on surveillance data and data collected through a structured telephone interview. With the use of multilevel logistic regression, the independent effect of hospital-related characteristics on SSI was assessed.

Thirty-six acute care hospitals in the Dutch surveillance network for nosocomial infections (PREZIES), from 1996 to 2000.

Thirteen thousand six hundred eighty patients who underwent total or partial hip arthroplasty.

A high annual volume of operations was associated with a reduced risk of SSI (risk-adjusted risk ratio [RR] per 50 extra operations, 0.85; 95% confidence interval [CI95], 0.74–0.97). With each extra full-time–equivalent infection control staff member per 250 beds available for prevention of SSI, the risk for SSI was decreased (RR, 0.48; CI95, 0.16–1.44), although the decrease was not statistically significant. Hospital size, teaching status, university affiliation, and number of surgeons and their years of experience showed no important association with the risk of SSI.

Undergoing surgery in a hospital with a low volume of operations increases a patient's risk of SSI.

To quantify the occurrence of surgical-site infections (SSIs) in an Italian region and to estimate the proportion of potentially avoidable infections through benchmarking comparison.

Prospective study during 1 month based on a convenience sample of surgical patients admitted to 31 public hospitals. All of the patients undergoing an intervention included among the 44 operative procedures of the National Nosocomial Infections Surveillance (NNIS) System were enrolled. Ninety-five percent of the patients were actively observed after discharge for up to 30 days for all of the operations and for up to 1 year for operations involving implantation.

Among the 6,167 operative procedures studied, 290 infections were recorded (4.7 per 100 procedures), 206 (71%) of which were SSIs (3.3 per 100 procedures; 95% confidence interval, 2.9–3.9). One hundred thirty-five SSIs (65.5%) were superficial infections, 53 (25.7%) were deep infections, and 12 (5.8%) were organ–space infections; in 6 cases (2.9%), the type of SSI was not recorded. The frequency of SSIs observed in this study was significantly higher for several procedures than that expected when the NNIS System rates (standardized infection ratio [SIR] ranging from 1.77 to 6.42) or the Hungarian rates (SIR ranging from 1.28 to 3.04) were applied to the study population.

The high intensity of postdischarge surveillance can in part explain the differences observed. To allow for meaningful benchmarking comparison, in addition to intrinsic patient risk, data on the intensity of postdischarge surveillance should be included in published reports.

To evaluate a multi-method approach to postdischarge surveillance of surgical-site infections (SSIs) and to identify infection rates and risk factors associated with SSI following cesarean section.

Cross-sectional survey.

Academic tertiary-care obstetric and gynecology center with 54 beds.

All women who delivered by cesarean section in Tartu University Women's Clinic during 2002.

Infections were identified during hospital stay or by postdischarge survey using a combination of telephone calls, healthcare worker questionnaire, and outpatient medical records review. SSI was diagnosed according to the criteria of the Centers for Disease Control and Prevention National Nosocomial Infections Surveillance System.

The multi-method approach gave a follow-up rate of 94.8%. Of 305 patients, 19 (6.2%; 95% confidence interval [CI95)], 3.8-9.6) had SSIs. Forty-two percent of these SSIs were detected during postdischarge surveillance. We found three variables associated with increased risk for developing SSI: internal fetal monitoring (odds ratio [OR], 16.6; CI95, 2.2-125.8; P = .007), chorioamnionitis (OR, 8.8; CI95, 1.1-69.6; P = .04), and surgical wound classes III and IV (OR, 3.8; CI95, 1.2-11.8; P=.02).

The high response rate validated the effectiveness of this kind of surveillance method and was most suitable in current circumstances. A challenge exists to decrease the frequency of internal fetal monitoring and to treat chorioamnionitis as soon as possible (Infect Control Hosp Epidemiol 2005;26:449-454).

To describe microbiological characteristics and epidemiologic features of an outbreak of postpartum endometritis.

Various markers were investigated in five patients and three throat carriage isolates of Streptococcus pyogenes obtained during an outbreak of endometritis occurring in a 13-week period. Molecular characterization included biotyping, T-serotyping, emm gene sequence and restriction, pulsed-field gel electrophoresis (PFGE), and random amplified polymorphic DNA (RAPD) analysis.

Biotype, T-serotype, and genotypic data (emm analysis, PFGE, and RAPD analysis) revealed a close relationship among the isolates from three patients, suggesting that cross-contamination had occurred. These isolates were biotype 1, T type 28, and emm type 28. The isolates from one patient and one carrier differed from those of the index patient by minor variations of the emm amplicon restriction pattern, PFGE pattern, or RAPD pattern. The remaining isolates were phenotypically and genetically different.

Identification of different isolates demonstrated that different strains may circulate simultaneously during a true outbreak and that the predominant strain might persist for several months.

In August 2001, the Centers for Disease Control and Prevention (CDC) notified the Texas Department of Health (TDH) of an unusually high number of wounds infected with group A streptococci (GAS) in an acute care facility. The TDH initiated an investigation, ultimately identifying 28 cases of non-pharyngeal, non-community-acquired GAS that had occurred between December 2000 and August 2001 and resulted in 3 deaths and 4 nonfatal cases of invasive disease. Ten specimens were sent to the CDC for emm typing; all isolates were emm type 114. However, the source of the outbreak could not be confirmed through laboratory testing at that time.

A case–control study was conducted comparing the 10 case-patients with 52 control-patients with wounds that were not infected with GAS. Age, gender, type of wound, underlying medical conditions, and treatment by the wound care team were examined for association with GAS infection.

The odds of having wound care team treatment versus not having it were 424.2 (95% confidence interval, 19.0 to 9,495.2) among case-patients when compared with control-patients. No other risk factor showed this magnitude of association.

This study provided overwhelming epidemiologic evidence that the wound care team was the means of transmission. One year later, when two patients receiving wound care were concurrently diagnosed as having GAS, a member of the wound care team was found to be GAS positive for the matching emm type. This is the first report of a GAS hospital outbreak linked to a wound care team.

To identify risk factors associated with surgical-site infection according to the depth of infection, the cardiac procedure, and the National Nosocomial Infections Surveillance System risk index.

Prospective survey conducted during a 12-month period.

A 48-bed cardiac surgical department in a teaching hospital.

Patients admitted for cardiac surgery between February 2002 and January 2003.

Surgical-site infections were diagnosed in 3% of the patients (38 of 1,268). Of the 38 surgical-site infections, 20 were superficial incisional infections and 18 were mediastinitis for incidence rates of 1.6% and 1.4%, respectively. Cultures were positive in 28 cases and the most commonly isolated pathogen was Staphylococcus. A National Nosocomial Infections Surveillance System risk index score of 2 or greater was associated with a risk of surgical-site infection (relative risk, 2.4; P < .004). Heart transplantation, mechanical circulatory assistance, coronary artery bypass graft with the use of internal mammary artery, and reoperation for cardiac tamponade or pericard effusion were independent risk factors associated with surgical-site infection.

Data surveillance using incidence rates stratified by cardiac procedure and type of infection is relevant to improving infection control efforts. Risk factors in patients who developed superficial infection were different from those in patients who developed mediastinitis. Coronary artery bypass graft using internal mammary artery was associated with a high risk of surgical-site infection, and independent factors such as reoperation for cardiac tamponade or pericard effusion increased the risk of infection.

To determine the incidence of and risk factors for surgical-site infections (SSIs) after abdominal surgery.

A cohort study was conducted from January to June 1998. CDC criteria for SSI and the NNIS System risk index were used.

A tertiary-care hospital in Peru.

Adult patients undergoing abdominal surgery who consented were enrolled and observed until 30 days after surgery. Patients who had undergone surgery at another hospital or who died or were transferred to another hospital within 24 hours after surgery were excluded.

Four hundred sixty-eight patients were enrolled. Their mean age was 37.2 years. One hundred twenty-five patients developed SSIs, 18% of which were identified after discharge. The overall incidence rate (IR) was 26.7%. The IR was 13.9% for clean, 15.9% for clean-contaminated, 13.5% for contaminated, and 47.2% for dirty interventions. The IR was 3.6% for NNIS System risk index 0 and 60% for index 3. Risk factors for SSI on logistic regression analysis were dirty or infected wound (RR, 3.8; CI95, 1.7-8.4), drain use longer than 9 days (RR, 6.0; CI95, 2.5-12.5), and length of surgery greater than the 75th percentile (RR, 2.1; CI95, 1.0-4.4). Patients with SSI had a longer hospital stay than did non-infected patients (14.0 vs 6.1 days; P < .001).

SSI is a major problem in this hospital, which has a higher IR (especially for clean interventions) than those of developed countries. In developing countries, prevention of SSI should include active surveillance and interventions targeting modifiable risk factors.

To analyze and model the patient and healthcare system factors that may interfere with the appropriate administration of surgical antimicrobial prophylaxis.

Between 1994 and 1998, surgical-site surveillance data were collected prospectively for a cohort of eligible surgical patients. For all cases, and each individual procedure (cardiothoracic, colonic, gynecologic, orthopedic, or vascular), forward stepwise multiple logistic regression was applied to relate key hospital and patient factors to an effective first prophylactic dose (ie, appropriate administration time, dose, route, and drug).

A 450-bed, tertiary-care teaching hospital in Canada.

A total of 4,835 patients admitted for surgical procedures who required antimicrobial prophylaxis.

Factors positive for an effective first prophylactic dose for all cases were when an order was written (OR, 19.7; CI95, 9.1–42.7; P < .001) and given in the operating room (OR, 13.9; Cl95, 7.5–25.6; P < .001). Factors negative for an effective first prophylactic dose were beta-lactam allergy (OR, 0.49; CI95, 0.4–0.61; P < .001) and same-day surgery (OR, 0.57; CI95, 0.4–0.82; P < .001).

With few exceptions, the four factors included in the procedure models showed that when a preoperative order was written or the antibiotic was given in the operating room, a patient was more likely to receive an effective first prophylactic dose. Conversely, when a patient had a beta-lactam allergy or the surgery was performed on the day the patient was admitted, the administration of an effective first prophylactic dose was less likely.

To compare the efficacies of ethylene oxide gas (EOG), hydrogen peroxide gas plasma (PLASMA), and low-temperature steam formaldehyde (LTSF) sterilization methods.

The efficacies of EOG, PLASMA, and LTSF sterilization were tested using metal and plastic plates, common medical instruments, and three process challenge devices with narrow lumens. All items were contaminated with Bacillus stearothermophilus spores or used a standard biological indicator.

EOG and LTSF demonstrated effective killing of B. stearothermophilus spores, with or without serum, on plates, on instruments, and in process challenge devices. PLASMA failed to adequately sterilize materials on multiple trials in several experiments, including two of three plates, two of three instruments, and all process challenge devices.

Our results suggest that PLASMA sterilization may be unsuccessful under certain conditions, particularly when used for items with complex shapes and narrow lumens. Alternatively, LTSF sterilization demonstrates excellent efficacy and is comparable to EOG sterilization. LTSF could potentially act as a substitute if EOG becomes unavailable due to environmental concerns.

To assess the efficacy of an alternative disinfection method for hospital water distribution systems contaminated with Legionella.

Disinfection with peracetic acid was performed in a small hospital contaminated with L. pneumophila serotype 1. The disinfectant was used at concentrations of 50 ppm (first three surveillance phases) and 1,000 ppm (fourth surveillance phase) for 30 minutes.

Environmental monitoring revealed that disinfection was maintained 1 week after treatment; however, levels of recontamination surpassing baseline values were detected after approximately 1 month. Comparison of water temperatures measured at the distal outlets showed a statistically significant association between temperature and bacterial load. The circulating water temperature was found to be lower in the two wards farthest away from the hot water production plant than in other wards. It was thought that the lower water temperature in the two wards promoted the bacterial growth even after disinfection.

Peracetic acid may be useful in emergency situations, but does not provide definitive protection even if used monthly.

To characterize the probability and duration of viral shedding among adults given trivalent live attenuated influenza vaccine (LATV).

Prospective surveillance study.

Nasal wash samples were collected from adult volunteers at baseline and on days 3, 7, and 10 and between days 17 and 21 following intranasal LAIV vaccination. The presence, titer, and identification of each specific strain of influenza virus shed were determined by standard methodology.

Twenty subjects received LATV. No samples were positive for influenza virus at baseline. After LAIV vaccination, influenza virus was recovered from 10 of 20 vaccinees on day 3, from 1 of 18 vaccinees on day 7, and from none of the samples on days 10 or 17 through 21. Vaccinees who shed vaccine virus were significantly younger than those who did not (mean age, 26.4 vs 38.6 years; P < .01). Although the presence of specific mucosal immunoglobulin A to influenza B was associated with significantly less shedding of influenza B after vaccination (P = .02), associations of shedding with other measures of immunity were not detected.

The duration of shedding of vaccine virus after LAIV in adults is limited and may be associated with an individual's prior influenza vaccination history.