To determine the cause and mode of transmission of a cluster of infections due to Enterobacter cloacae.

Retrospective cohort study in a neonatal intensive-care unit (NICU) from December 1996 to January 1997; environmental and laboratory investigations.

60 infants hospitalized in the NICU during the outbreak period.

Odds ratios (OR) linking E cloacae colonization or infection and various exposures. All available E cloacae isolates were typed and characterized by contour-clamped homogenous electric-field electrophoresis to confirm possible cross-transmission.

Of eight case-patients, two had bacteremia; one, pneumonia; one, soft-tissue infection; and four, respiratory colonization. Infants weighing <2,000 g and born before week 33 of gestation were more likely to become cases (P<.001). Multivariate analysis indicated that the use of multidose vials was independently associated with E cloacae carriage (OR, 16.3; 95% confidence interval [CI95], 1.8-∞ P=011). Molecular studies demonstrated three epidemic clones. Cross-transmission was facilitated by understaffing and overcrowding (up to 25 neonates in a unit designed for 15), with an increased risk of E cloacae carriage during the outbreak compared to periods without understaffing and overcrowding (relative risk, 5.97; CI95, 2.2-16.4). Concurrent observation of healthcare worker (HCW) handwashing practices indicated poor compliance. The outbreak was terminated after decrease of work load, increase of hand antisepsis, and reinforcement of single-dose medication.

Several factors caused and aggravated this outbreak: (1) introduction of E cloacae into the NICU, likely by two previously colonized infants; (2) further transmission by HCWs' hands, facilitated by substantial overcrowding and understaffing in the unit; (3) possible contamination of multidose vials with E cloacae. Overcrowding and understaffing in periods of increased work load may result in outbreaks of nosocomial infections and should be avoided.

Assessment of the distribution of tasks and consultations provided by the hospital epidemiologist (HE) at University Hospital of Zurich (UHZ).

Prospective collection of data on hospital epidemiology consultations over a 3-year period (1995-1997). Time spent per consultation and activities of infection control practitioners were not recorded.

A 1,040-bed tertiary-care university hospital in Zurich, Switzerland.

Between January 1, 1995, and December 31, 1997, the HE received 1,660 requests for consultation. Advice or action was sought in the following areas: epidemiology (27.5% of requests); quality assurance, including antibiotic utilization and technology assessment (24.8%); infection control and practice guidelines (22.5%); disinfection and sterilization (11.6%); clinical infectious diseases (13.4%). During 1997, 35% of epidemiology consults were related to methicillin-resistant Staphylococcus aureus and 5.8% to tuberculosis. Public or private hospitals not affiliated with UHZ requested 40% of all consults.

This study shows that HEs are involved in many different activities. Only 27.5% of hospital epidemiology consultations were directly related to issues of epidemiology. Practical knowledge of the methodologies for continuous quality improvement and assessment of various new technologies is important for HEs. The results of this study may be useful in discussions between HEs and administrators about allocation of resources or issues of reimbursement.

To study the incidence of tuberculosis (TB), tuberculin skin testing (TST) practices, and infection control practices at outpatient hemodialysis centers.

Mail surveys performed in December 1994 and 1995.

The numbers of patients with incident active TB during 1994 and 1995, TST policies during 1994, and TB infection control policies in 1994.

All outpatient dialysis centers in New Jersey.

Healthcare workers and patients in dialysis centers in New Jersey.

Of 47 centers, 41 provided information on TST and TB infection control policies and practices. TSTs were performed on newly hired healthcare workers at all 41 centers and on established workers at 39 centers. In contrast, only 1 center reported performing TSTs on hemodialysis patients; 5 other centers reported screening of patients for TB using chest radiographs. Active TB was reported in 3 of 4,550 chronic hemodialysis patients in 1994 (rate, 66/100,000 patient-years) and in 4 of 4,831 patients in 1995 (rate, 83/100,000 patient-years). Both rates were several times higher than the rate in the New Jersey general population during this period (10.7-10.8/100,000).

Although based on small numbers of patients with TB, we found a relatively high incidence of TB among hemodialysis patients in New Jersey. Most centers reported performing TSTs on workers but not on patients. These results suggest the need for improved TB screening and infection control precautions at outpatient dialysis centers.

To assess the practice of antimicrobial prophylaxis for surgical procedures in eight surgical departments in a 550-bed teaching hospital.

A list of all major procedures performed in our hospital, with recommendations for prophylaxis based upon the literature, has been distributed since 1993 and is updated periodically. The practice of surgical prophylaxis between January 1 and March 31,1996, was examined by assessing four variables: (1) Did the particular procedure justify prophylaxis, and was it provided? (2) Was timing optimal, ie, within 1 hour prior to surgery? (3) Was the appropriate antimicrobial selected? (4) Was duration optimal, ie, ≤24 hours?

During the study period, 2,117 operations were performed, of which 1,631 (77%) were reviewed. Sixty-six percent were clean surgery, 28% clean-contaminated, and 6% contaminated; 72% of procedures were elective, 28% emergencies. Of 1,631 operations requiring prophylaxis, 1,142 (70%) received it, 489 (30%) did not. Of 1,631 patients, 1,392 (85%) received appropriate care: 929 (67%) appropriately received prophylaxis, and 463 (33%) appropriately did not receive prophylaxis. Of 955 patients who received prophylaxis, 26 (3%) did so inappropriately. Of 1,142 patients who should have received prophylaxis, 213 (19%) did not receive it. Female gender, clean surgery, elective operations, and infrequently performed procedures were all significant indicators of inappropriately withheld prophylaxis (P<.001). In addition, the rate of appropriately provided prophylaxis varied between departments from 71% to 97% (P<.001). Assessment of the 929 procedures for which prophylaxis was justified and given revealed that 100% of patients received it on time, the choice of antimicrobial was appropriate in 95% of cases, and duration was ≤24 hours in 91%.

Audits of surgical prophylaxis are expected to detect different errors in different institutions. Conducting audits of surgical prophylaxis probably should be part of the routine activity of infection control teams. Feeding the information back to surgeons could improve adherence to recommended guidelines and might contribute to reduced wound infection rates.

To document the costs and the benefits (both in terms of costs averted and of injuries averted) of education sessions and replacement of phlebotomy devices to ensure that needle recapping did not take place.

The percentage of recapped needles and the rate of needlestick injuries were evaluated in 1990 and 1997, from a survey of transparent rigid containers in the wards and at the bedside and from a prospective register of all injuries in the workplace. Costs were computed from the viewpoint of the hospital. Positive costs were those of education and purchase of safer phlebotomy devices; negative costs were the prophylactic treatments and follow-up averted by the reduction in injuries.

A 1,050-bed tertiary-care university hospital in the Paris region.

Between the two periods, the proportion of needles seen in the containers that had been recapped was reduced from 10% to 2%. In 1990, 127 needlestick (12.7/100,000 needles) and 52 recapping injuries were reported versus 62 (6.4/100,000 needles) and 22 in 1996 and 1997. When the rates were related to the actual number of patients, the reduction was 76 injuries per year. The total cost of information and preventive measures was $325,927 per year. The cost-effectiveness was $4,000 per injury prevented.

Although preventive measures taken to ensure reduction of needlestick injuries appear to have been effective (75% reduction in recapping and 50% reduction in injuries), the cost of the safety program was high.