To measure infection rates in a regional cohort of long-term-care facilities (LTCFs) using standard surveillance methods and to analyze different methods for interfacility comparisons.

Seventeen LTCFs in Idaho.

Prospective, active surveillance for LTCF-acquired infections using standard definitions and case-finding methods was conducted from July 2001 to June 2002. All surveillance data were combined and individual facility performance was compared with the aggregate employing a variety of statistical and graphic methods.

The surveillance data set consisted of 472,019 resident-days of care with 1,717 total infections for a pooled mean rate of 3.64 infections per 1,000 resident-days. Specific infections included respiratory (828; rate, 1.75), skin and soft tissue (520; rate, 1.10), urinary tract (282; rate, 0.60), gastrointestinal (77; rate, 0.16), unexplained febrile illnesses (6; rate, 0.01), and bloodstream (4; rate, 0.01). Initially, methods adopted from the National Nosocomial Infections Surveillance System were used comparing individual rates with pooled means and percentiles of distribution. A more sensitive method appeared to be detecting statistically significant deviations (based on chi-square analysis) of the individual facility rates from the aggregate of all other facilities. One promising method employed statistical process control charts (U charts) adjusted to compare individual rates with aggregate monthly rates, providing simultaneous visual and statistical comparisons. Small multiples graphs were useful in providing images valid for rapid concurrent comparison of all facilities.

Interfacility comparisons have been demonstrated to be valuable for hospital infection control programs, but have not been studied extensively in LTCFs.

We describe an effort to reduce transmission of a multidrug-resistant Streptococcus pneumoniae (MDRSP) in a long-term-care facility (LTCF).

Longitudinal cross-sectional study.

An LTCF in New York City with ongoing disease due to an MDRSP strain among residents with AIDS since a 1995 outbreak. The MDRSP outbreak strain was susceptible to vancomycin but not to other antimicrobials tested, including fluoroquinolones.

Residents and staff members of the LTCF during 1999 through 2001.

Implementing standard infection control measures, and developing and implementing "enhanced standard" infection control measures, modified respiratory droplet prevention measures to reduce inter-resident transmission.

Before the intervention, nasopharyngeal carriage of the MDRSP outbreak strain was detected in residents with AIDS and residents with tracheostomies who were not dependent on mechanical ventilation. The prevalence of nasopharyngeal carriage of the MDRSP outbreak strain was 7.8% among residents who had AIDS and 14.6% among residents with tracheostomies. After training sessions on standard and enhanced standard infection control measures, the staff appeared to have good knowledge and practice of the infection control measures. After the intervention, new transmission among residents with tracheostomies was prevented; however, these residents were prone to persistent tracheal carriage and needed ongoing enhanced standard infection control measures. Ongoing transmission among residents with AIDS, a socially active group, was documented, although fewer cases of disease due to the outbreak strain occurred.

Infection control contributed to less transmission of MDRSP in the LTCF. Additional strategies are needed to reduce transmission and carriage among certain resident populations.

To characterize risk factors associated with pneumococcal disease and asymptomatic colonization during an outbreak of multidrug-resistant Streptococcus pneumoniae (MDRSP) among AIDS patients in a long-term–care facility (LTCF), evaluate the efficacy of antimicrobial prophylaxis in eliminating MDRSP colonization, and describe the emergence of fluoroquinolone resistance in the MDRSP outbreak strain.

Epidemiologic investigation based on chart review and characterization of SP strains by antimicrobial susceptibility testing and PFGE and prospective MDRSP surveillance.

An 80-bed AIDS-care unit in an LTCF.

Staff and residents on the unit.

From April 1995 through January 1996, 7 cases of MDRSP occurred. A nasopharyngeal (NP) swab survey of all residents (n = 65) and staff (n = 70) detected asymptomatic colonization among 6 residents (9%), but no staff. Isolates were sensitive only to rifampin, ofloxacin, and vancomycin. A 7-day course of rifampin and ofloxacin was given to eliminate colonization among residents: NP swab surveys at 1, 4, and 10 weeks after prophylaxis identified 1 or more colonized residents at each follow-up with isolates showing resistance to one or both treatment drugs. Between 1996 and 1999, an additional 6 patients were diagnosed with fluoroquinolone-resistant (FQ-R) MDRSP infection, with PFGE results demonstrating that the outbreak strain had persisted 3 years after the initial outbreak was recognized.

Chemoprophylaxis likely contributed to the development of a FQ-R outbreak strain that continued to be transmitted in the facility through 1999. Long-term control of future MDRSP outbreaks should rely primarily on vaccination and strict infection control measures.

In Victoria, Australia, from July to December 2002, 126 outbreaks of viral and suspected viral gastroenteritis were reported in healthcare institutions. Norovirus was found to account for at least 77 of the 126 outbreaks.

In October 2002, the infection control unit investigated an outbreak of acute gastroenteritis on three wards in a 500-bed, long-term-care facility in Melbourne, Victoria, Australia. Cohorting and other infection control measures were initiated.

The outbreak was controlled 32 days after the first symptoms of acute gastroenteritis were identified. Fifty-two patients and 11 staf f members were affected. Norovirus genotype 2 was detected on two of the three wards. Norovirus was not isolated in the third ward but was suspected to be the causative organism.

Outbreaks of viral gastroenteritis can cause significant morbidity in a long-term-care facility, affecting both patients and staff. In addition, the transmission of viral pathogens can be well established before there is recognition of an outbreak.

Norovirus belongs to the Caliciviridae family and causes outbreaks of infectious enteritis by fecal-oral transmission. In Spain, there have been few outbreaks reported due to this virus. We describe an outbreak on a long-term-care hospital ward.

Cases were classified as probable, confirmed, and secondary. Stool cultures were performed. Polymerase chain reaction detection of norovirus was also performed.

The outbreak occurred from December 7 to 28, 2001, involving 60 cases (32 patients, 19 staff members, 8 patients' relatives, and 1 relative of a staff member). Most (82%) of the cases were female. The most frequently involved ages were 20 to 39 years for staff members and 70 to 89 years for patients. The incubation period of secondary cases in patients' families had a median of 48 hours (range, 1 to 7 days). Clinical symptoms included diarrhea (85%), vomiting (75%), fever (37%), nausea (23%), and abdominal pain (12%). Median duration of the disease was 48 hours (range, 1 to 7 days). All cases resolved and the outbreak halted with additional hygienic measures. Stool cultures were all negative for enteropathogenic bacteria and rotaviruses. In 16 of 23 cases, the norovirus genotype 2 antigen was detected.

This outbreak of gastroenteritis due to norovirus genotype 2 affected patients, staff members, and their relatives in a long-term-care facility and was controlled in 21 days.

To describe a nosocomial norovirus outbreak, its management, and its financial impact on hospital resources.

A matched case-control study and microbiological investigation.

We compared 16 patients with norovirus infection with control-patients matched by age, gender, disease category, and length of stay. Bed occupancy-days during the peak incidence period of the outbreak were compared with the corresponding periods in 2001 and 2002. Expenses due to increased workload were calculated based on a measuring system that records time spent for nursing care per patient per day.

The attack rates were 13.9% among patients and 29.5% among healthcare workers. The median number of occupied beds was significantly lower due to bed closure during the peak incidence in 2003 (29) compared with the median number of occupied beds in 2001 and 2002 combined (42.5). Based on this difference and a daily charge of $562.50 per patient, we calculated a revenue loss of S37.968. Additional expenses totaled $10,300 for increased nursing care. Extra costs for microbiological diagnosis totaled $2,707. Lost productivity costs due to healthcare workers on sick leave totaled $12,807. The expenses for work by the infection control team totaled $1,408. The financial impact of this outbreak on hospital resources comprising loss of revenue and extra costs for microbiological diagnosis but without lost productivity costs, increased nursing care, and expenses for the infection control team totaled $40,675.

Nosocomial norovirus outbreaks result in significant loss of revenue and increased use of resources. Bed closures had a greater impact on hospital resources than increased need for nursing care.

To study the dependence of infection risk and outbreak size on the type of index case (ie, patient or staff).

Nosocomial outbreaks were reviewed and categorized into those started by patients and those started by staff. Infection risks and outbreak sizes were evaluated taking into account the index case category.

Of the 30 nosocomial outbreaks of norovirus with person-to-person transmission, 20 (67%) involved patients as the index cases. Patient-indexed outbreaks affected significantly more patients than did staff-indexed outbreaks (difference in means, 16.25; 95% confidence interval [CI95], 5.1 to 27.0). For the numbers of affected staff, no dependence on the index case category was detectable (difference in means, -1.05; CI95, -9.0 to 6.9). For patients exposed during patient-indexed outbreaks, the risk of acquiring a norovirus infection was approximately 4.8 times as high as the corresponding risk for patients exposed during staff-indexed outbreaks (odds ratio [OR], 4.79; CI95,1.82 to 8.28). The infection risk for exposed staff during patient-indexed outbreaks was approximately 1.5 times as high as the corresponding risk during staff-indexed outbreaks (OR, 1.51; CI95, 0.92 to 2.49).

Patient-indexed norovirus outbreaks generally affect more patients than do staff-indexed outbreaks. Staff appear to be similarly affected by both outbreak index category groups. This study demonstrates the importance of obtaining complete outbreak data, including the index case classification as staff or patient, during norovirus outbreak investigations. Such information may be useful for further targeting prevention measures.

Fluoroquinolones have not been frequently implicated as a cause of Clostridium difficile outbreaks. Nosocomial C. difficile infections increased from 2.7 to 6.8 cases per 1,000 discharges (P < .001). During the first 2 years of the outbreak, there were 253 nosocomial C. difficile infections; of these, 26 resulted in colectomy and 18 resulted in death. We conducted an investigation of a large C. difficile outbreak in our hospital to identify risk factors and characterize the outbreak.

A retrospective case-control study of case-patients with C. difficile infection from January 2000 through April 2001 and control-patients matched by date of hospital admission, type of medical service, and length of stay; an analysis of inpatient antibiotic use; and antibiotic susceptibility testing and molecular subtyping of isolates were performed.

On logistic regression analysis, clindamycin (odds ratio [OR], 4.8; 95% confidence interval [CI95], 1.9-12.0), ceftriaxone (OR, 5.4; CI95, 1.8-15.8), and levofloxacin (OR, 2.0; CI95, 1.2-3.3) were independently associated with infection. The etiologic fractions for these three agents were 10.0%, 6.7%, and 30.8%, respectively. Fluoroquinolone use increased before the onset of the outbreak (P < .001); 59% of case-patients and 41% of control-patients had received this antibiotic class. The outbreak was polyclonal, although 52% of isolates belonged to two highly related molecular subtypes.

Exposure to levofloxacin was an independent risk factor for C. difficile-associated diarrhea and appeared to contribute substantially to the outbreak. Restricted use of levofloxacin and the other implicated antibiotics may be required to control the outbreak.

Economic evaluation has become increasingly important in healthcare and infection control. This study evaluated the impact of nosocomial infections on cost of illness and length of stay (LOS) in intensive care units (ICUs).

A retrospective cohort study.

Medical, surgical, and mixed medical and surgical ICUs in a tertiary-care referral medical center.

Patients admitted to adult ICUs between October 2001 and June 2002 were eligible for the study.

Estimates of the cost and LOS for patients who acquired a nosocomial infection were computed using a stratified analysis and regression approach.

During the study period, 778 patients were admitted to the ICUs. Total costs for patients with and without nosocomial infections (median cost, $10,354 and $3,985, respectively) were significantly different (P < .05). The costs stratified by infection site (median differences from $4,687 to $7,365) and primary diagnosis (median differences from $5,585 to $16,507) were also significantly different (P < .05) except for surgical-site infection. After covariates were adjusted for in the multiple linear regression, nosocomial infection increased the total costs by $3,306 per patient and increased the LOS by 18.2 days per patient (P < .001). Each additional day spent in the ICU increased the cost per patient by $353 (P < .001).

Nosocomial infections are associated with increased cost of illness and LOS. Prevention of nosocomial infections should reduce direct costs and decrease the LOS.

Bordetella pertussis is highly contagious, and because immunity wanes after vaccination, it continues to be a cause of cough among adults.

To describe the healthcare services used and productivity losses accrued by healthcare workers (HCWs) missing work due to pertussis.

After 3 pertussis cases were confirmed among HCWs, all hospital employees and patients with a cough were screened between November 2000 and March 2001. Each potential case underwent diagnostic tests and received antibiotics (spiramycin or azithromycin) when appropriate. Symptomatic employees were not allowed to return to work until they received an antibiotic for at least 5 days. Services used (physician visits and calls, antibiotics, diagnostic tests, hospitalization, and treatment provided to their contacts) were combined with cost estimates (in 2002 euros) for these services in France.

Ninety-one potential cases were identified (77 HCWs, 12 patients, and 2 family members). Of them, 89% received antibiotics and 22% had at least one contact who was also treated. Approximately half (55%) of the HCWs who were cases missed 5 days of work. Four patients were admitted to the hospital as a result of the infection. The average medical cost was 297 euros per potential case: diagnostic tests accounted for 32% and hospitalization for 31%. Total cost (medical and productivity) was 46,661 euros for 91 cases, 42% from productivity losses. An investigation to identify these potential cases also accrued additional costs.

Serious adverse health and economic consequences arose from transmission of pertussis among HCWs, their families, and patients.

To identify the independent effect of pressure ulcers on excess length of stay and control for all observable factors that may also contribute to excess length of stay. Hospitalized patients who develop a pressure ulcer during their hospital stay are at a greater risk for increased length of stay as compared with patients who do not.

Cross-sectional, observational study.

Tertiary-care referral and teaching hospital in Australia.

Two thousand hospitalized patients 18 years and older who had a minimum stay in the hospital of 1 night and admission to selected clinical units.

Two thousand participants were randomly selected from 4,500 patients enrolled in a prospective survey conducted between October 2002 and January 2003. Quantile median robust regression was used to assess risk factors for excess length of hospital stay.

Having a pressure ulcer resulted in a median excess length of stay of 4.31 days. Twenty other variables were statistically significant at the 5% level in the final model.

Pressure ulcers make a significant independent contribution to excess length of hospitalization beyond what might be expected based on admission diagnosis. However, our estimates were substantially lower than those currently used to make predictions of the economic costs of pressure ulcers; existing estimates may overstate the true economic cost.

To assess the level of knowledge regarding and attitudes toward standard and isolation precautions among healthcare workers in a hospital.

A confidential, self-administered questionnaire survey was conducted in a random sample of 1,500 nurses and 500 physicians in a large teaching hospital.

A total of 1,241 questionnaires were returned (response rate, 62%). The median age of respondents was 39 years; 71.9% were women and 21.2% had senior staff status. One-fourth had previously participated in specific training regarding transmission precautions for pathogens conducted by the infection control team. More than half (55.9%) gave correct answers to 10 or more of the 13 knowledge-type questions. The following reasons for noncompliance with guidelines were judged as “very important”: lack of knowledge (47%); lack of time (42%); forget-Mness (39%); and lack of means (28%). For physicians and healthcare workers in a senior position, lack of time and lack of means were significantly less important (P < .0005). On multivariate linear regression, knowledge was independently associated with exposure to training sessions (coefficient, 0.33; 95% confidence interval, 0.08 to 0.57; P = .009) and less professional experience (coefficient per increasing professional experience, -0.024; 95% confidence interval, -0.035 to -0.012; P < .0005).

Despite a training effort targeting opinion leaders, knowledge of transmission precautions for pathogens remained insufficient. Nevertheless, specific training proved to be the major determinant of “good knowledge”.

Infectious complications are frequent among critically ill neonates. Hand hygiene is the leading measure to prevent healthcare-associated infections, but poor compliance has been repeatedly documented, including in the neonatal setting. Hand hygiene promotion requires a complex approach that should consider personal factors affecting healthcare workers' attitudes.

To identify beliefs and perceptions associated with intention to comply with hand hygiene among neonatal healthcare workers.

An anonymous, self-administered questionnaire (74 items) based on the theory of planned behavior was distributed to 80 neonatal healthcare workers to assess intention to comply, attitude toward hand hygiene, behavioral and subjective norm perceptions, and perception of difficulty to comply. Variables were assessed using multi-item measures and answers to 7-point bipolar scales. All multi-item scales had satisfactory internal consistency (alpha > 0.7). Multivariate logistic regression identified independent perceptions or beliefs associated with a positive intention to comply.

The response rate was 76% (61 of 80). Of the 49 nurses and 12 physicians responding, 75% believed that they could improve their compliance with hand hygiene. Intention to comply was associated with perceived control over the difficulty to perform hand hygiene (OR, 3.12; CI95, 1.12 to 8.70; P = .030) and a positive perception of how superiors valued hand hygiene (OR, 2.89; CI95, 1.08 to 7.77; P = .035).

Our data highlight the importance of the opinions of superiors and a strong perceived controllability over the difficulty to perform hand hygiene as possible internal factors that may influence hand hygiene compliance.

The hands of healthcare workers often transmit pathogens causing nosocomial infections. This study examined compliance with handwashing and glove use.

A university-affiliated hospital.

Compliance was observed covertly. Healthcare workers' demographics, hand hygiene facilities, indications for hand hygiene, compliance with handwashing and glove use in each procedure, and duration of handwashing were recorded.

Nine nurses and 33 assistant physicians were monitored during the study. One researcher recorded 1,400 potential opportunities for handwashing during 15-minute observation periods. The mean duration of handwashing was 10 + 2 seconds. Most healthcare workers (99.3%) used liquid soap during handwashing, but 79.8% did not dry their hands. For all indications, compliance with handwashing was 31.9% and compliance with glove use was 58.8%. Compliance with handwashing varied inversely with both the number of indications for hand hygiene and the number of patient beds in the hospital room. Compliance with handwashing was better in dirty high-risk situations.

Compliance with handwashing was low, suggesting the need for new motivational strategies such as supplying feedback regarding compliance rates.

To evaluate warm air and paper towel drying for removing bacteria from washed hands.

After hands were washed with non-antibacterial soap, they were dried using warm air with and without ultraviolet light, while being rubbed or held stationary, or paper towels. Each method was performed as a randomized trial using 30 hands.

Log colony-forming units (CFU) on palms and fingers increased significantly when hands were dried with warm air while being rubbed for 15 seconds (P < .001), and many bacteria remained at 30 seconds without ultraviolet light (P < .001). Holding hands stationary while drying significantly decreased log CFU on palms, fingers, and fingertips (P < .01 or < .001). Few CFU were detected on palms and fingers dried with ultraviolet light. Although log CFU of palms and fingers did not decrease after drying with three sheets of paper towel, those of fingertips decreased significantly (P < .001). For palms and fingers, log reductions were greater with warm air drying while holding hands stationary, paper towels, and warm air drying while rubbing hands. For fingertips, the log reduction was often greater with paper towels than with warm air.

Holding hands stationary and not rubbing them was desirable for removing bacteria. Ultraviolet light reinforced the removal of bacteria during warm air drying. Paper towels were useful for removing bacteria from fingertips but not palms and fingers.

To evaluate the effect of an infection control program on the incidence of hospital-acquired infection (HAI) and associated mortality.

Prospective study.

A 2,000-bed, university-affiliated hospital in Italy.

All patients admitted to the general intensive care unit (ICU) for more than 48 hours between January 2000 and December 2001.

The infection control team (ICT) collected data on the following from all patients: demographics, origin, diagnosis, severity score, underlying diseases, invasive procedures, HAI, isolated microorganisms, and antibiotic susceptibility.

Regular ICT surveillance meetings were held with ICU personnel. Criteria for invasive procedures, particularly central venous catheters (CVCs), were modified. ICU care was restricted to a team of specialist physicians and nurses and ICU antimicrobial therapy policies were modified.

Five hundred thirty-seven patients were included in the study (279 during 2000 and 258 in 2001). Between 2000 and 2001, CVC exposure (82.8% vs 71.3%; P < .05) and mechanical ventilation duration (11.2 vs 9.6 days) decreased. The HAI rate decreased from 28.7% in 2000 to 21.3% in 2001 (P < .05). The crude mortality rate decreased from 41.2% in 2000 to 32.9% in 2001 (P < .05). The most commonly isolated microorganisms were nonfermentative gram-negative organisms and staphylococci (particularly MRSA). Mortality was associated with infection (relative risk, 2.11; 95% confidence interval, 1.72-2.59; P <.05).

Routine surveillance for HAI, coupled with new measures to prevent infections and a revised policy for antimicrobial therapy, was associated with a reduction in ICU HAIs and mortality.