To investigate the presence and clonal distribution of Legionella species in the water supply of 20 hospitals in Catalonia, Spain.

20 hospitals in Catalonia, an area of 32,000 km2, located in northeast Spain.

Environmental cultures of 186 points of potable water supply and 10 cooling towers were performed for the presence of Legionella species. Following filtration and acid treatment, the samples were seeded in selective MWY (modified Wadowsky Yee)-buffered charcoal yeast extract-a agar. All isolates obtained were characterized microbiologically and genotyped by Sfil pulsed-field gel electrophoresis (PFGE).

73 of 196 water samples, representing 17 of the 20 hospitals included in the study, were positive for Legionella pneumophila (serogroups 1, 2-14, or both). The degree of contamination ranged from 200 to 74,250 colony-forming units/L. Twenty-five chromosomal DNA subtypes were detected by PFGE. A single DNA subtype was identified in 10 hospitals, 2 DNA subtypes were observed in 6 hospitals, and 1 hospital exhibited 3 different DNA subtypes. Each hospital had its own Legionella DNA subtype, which was not shared with any other hospitals.

Legionella was present in the water of most of the hospitals studied; each such hospital had a unique, dominant chromosomal DNA subtype. The verification of several genomic DNA restriction profiles in such a small geographic area demonstrates the great genetic diversity of Legionella in the aquatic environment.

To assess the way French hospitals conduct surveillance for, and control infections caused by, methicillin-resis-tant Staphylococcus aureus (MRSA), and to evaluate the incidence of these infections.

Retrospective analysis of sample surveillance data.

Representative sample of French hospitals.

Representative sample of 38 French public hospitals.

Hospitals were selected randomly in 1996, taking into account their location and number of beds. Administrative data, surveillance denominators used, antimicrobial resistance rates, and infection control practices were analyzed for the period 1990 to 1995. The same 38 centers were contacted 3 years later, in 1998, to reassess their surveillance and control activities.

French hospitals were slow to implement MRSA surveillance programs; only 5% had such programs in 1990, when the median incidence per admission (0.37%) and per patient-days (0.04%) of MRSA infections was already high. Despite the implementation of surveillance programs in 66% of French hospitals in 1995 and 87% in 1998, the MRSA infection rates remained stable from 1990 to 1995 and increased from 1995 to 1998. The proportion of French hospitals having a policy for the transfer of MRSA-infected patients to other hospitals increased from 47% in 1995 to 61% in 1998, whereas screening for MRSA colonization (42%-53%) and isolation for colonized or infected patients (87%-89%) remained stable.

This first national survey showed that French hospitals probably were not optimally prepared to control and prevent MRSA infections, since they were slow to respond to the growing problem.

To investigate the background of changes of resistance phenotypes in methicillin-resistant Staphylococcus aureus (MRSA) from nosocomial infections in German hospitals by molecular typing and identification of particular resistance genes.

Isolates from the network for monitoring the spread of MRSA in Germany were subjected to quantitative susceptibility testing, to molecular typing, and to polymerase chain reaction identification of resistance genes.

The network consists of 175 German clinical microbiological laboratories collaborating with the German Reference Center for Staphylococci, which performs typing of staphylococcal isolates from nosocomial infections and data analysis.

During the past 5 years, MRSA susceptible to other antibiotics such as oxytetracycline, erythromycin, and gentamicin became more frequent. The proportion of epidemic MRSA clones that had been disseminated in the past and that exhibited broad resistance phenotypes decreased, whereas the proportion of recently emerging MRSA carrying only a few other resistance determinants has increased (1994, 11.5%; 1998, 39%).

The changing pattern of resistance phenotypes of MRSA from nosocomial infections in Germany is mainly due to the spread of recently emerging epidemic strains that are less frequently resistant to antibacterials other than oxacillin. The observed changes cannot simply be attributed to overall antibiotic consumption.

To determine the impact of methicillin-resis-tant Staphylococcus aureus (MRSA) colonization on the occurrence of S aureus infections (methicillin-resistant and methicillin-suscep-tible), the use of glycopeptides, and outcome among intensive care unit (ICU) patients.

Prospective observational cohort survey.

A medical-surgical ICU with 10 single-bed rooms in a 460-bed, tertiary-care, university-affiliated hospital.

A total of 1,044 ICU patients were followed for the detection of MRSA colonization from July 1, 1995, to July, 1 1998.

MRSA colonization was detected using nasal samples in all patients plus wound samples in surgical patients within 48 hours of admission or within the first 48 hours of ICU stay and weekly thereafter. MRSA infections were defined using Centers for Disease Control and Prevention standard definitions, except for ventilator-associated pneumonia and catheter-related infections, which were defined by quantitative distal culture samples.

One thousand forty-four patients (70% medical patients) were included in the analysis. Mean age was 61±18 years; mean Simplified Acute Physiologic Score (SAPS) II was 36.4±20; and median ICU stay was 4 (range, 1-193) days. Two hundred thirty-one patients (22%) died in the ICU. Fifty-four patients (5.1%) were colonized with MRSA on admission, and 52 (4.9%) of 1,044 acquired MRSA colonization in the ICU. Thirty-five patients developed a total of 42 S aureus infections (32 MRSA, 10 methi-cillin-susceptible). After factors associated with the development of an S aureus infection were adjusted for in a multivariate Cox model (SAPS II >36: hazard ratio [HR], 1.64; P=.09; male gender: HR, 2.2; P=.05), MRSA colonization increased the risk of S aureus infection (HR, 3.84; P=.0003). MRSA colonization did not influence ICU mortality (HR, 1.01; P=.94). Glycopeptides were used in 11.4% of the patients (119/1,044) for a median duration of 5 days. For patients with no colonization, MRSA colonization on admission, and ICU-acquired MRSA colonization, respectively, glycopeptide use per 1,000 hospital days was 37.7, 235.2, and 118.3 days. MRSA colonization per se increased by 3.3-fold the use of glycopeptides in MRSA-colonized patients, even when an MRSA infection was not demonstrated, compared to non-colonized patients.

In our unit, MRSA colonization greatly increased the risk of S aureus infection and of glycopeptide use in colonized and non-colonized patients, without influencing ICU mortality. MRSA colonization influenced glycopeptide use even if an MRSA infection was not demonstrated; thus, an MRSA control program is warranted to decrease vancomycin use and to limit glycopeptide resistance in gram-positive cocci.

To assess the risk of nosocomial infection in transferred patients and to determine whether transfer is only a risk marker or is independently associated with nosocomial infection.

Retrospective analysis.

A 400-bed general hospital in the Paris area.

All the patients hospitalized on the days of the surveys were included.

Epidemiological analysis of data collected in four annual nosocomial infection prevalence surveys conducted between 1993 and 1996.

Of the 1,326 patients included in the four surveys, 70 (5.3%) had been transferred from another hospital and 199 (15.0%) from another ward of our hospital. Transferred patients more frequently had known risk factors of nosocomial infection: age >65 years (P<10-5), a length of hospital stay >7 days on the day of the survey (P<10-6), at least one invasive procedure (34.2% vs 27.2%; P<.05), a recent surgical intervention (P<.05), and an immunosuppression (P<.01). The prevalence rate of infected patients was 6.7% (95% confidence interval, 5.3-8.1). The risk of being infected on a given day was more than 4 times higher in transferred patients (P<10-6); however, the risk was similar between patients transferred from another hospital (20.0%) and patients transferred within the hospital (17.1%). The multivariate analysis performed by logistic regression showed that intrahospi-tal transfer, a length of hospital stay >7 days, and having had at least one invasive procedure were independent risk factors of infection.

According to this study, patient transfer is both a risk marker (associated with several known risk factors) and independently associated with nosocomial infection. The origin of a transferred patient is readily known at admission. It would be useful to adopt specific measures for such patients, particularly if they have other risk factors of nosocomial infection, both to protect them and to prevent transmission of the infection to other hospitalized patients.

To describe an outbreak of hepatitis C in a clinical research study.

Observational study.

Tertiary-care hospital.

Healthcare workers who volunteered to be subjects in a study of the metabolic effects of inhaled and oral corticosteroids who were unwittingly exposed to hepatitis C virus (HCV).

Epidemiological investigation and serological analyses.

One chronic carrier of HCV was identified. Four fellow workers volunteering in the studies became infected with HCV, with 96% homology among strains. There was no evidence of spread from infected healthcare workers to patients on whom they had performed arterial punctures (2 of 214 positive, unrelated to each other and to the outbreak strain).

Infection control standards in clinical research must be maintained vigorously to prevent transmission of blood-borne pathogens such as HCV.

To identify the routes of transmission in a nosocomial outbreak of hepatitis C virus (HCV) infection.

Epidemiological investigation, including screening for HCV of hospitalized patients, and a retrospective cohort study, review of hygiene and medical practices, and molecular comparison of HCV isolates.

A specialized care unit for cystic fibrosis (CF) and diabetic patients at an acute-care facility in the south of France.

Of the 57 CF patients (age in 1995: 2-28 years), 38 (66.7%) were tested and 22 (57.9%) were anti-HCV positive. Eight (50%) of 16 patients with anti-HCV antibody tested by polymerase chain reaction were viremic. No patients had received blood products or had any history of intravenous drug use. All 18 (100%) patients with CF who had ever undergone self-monitoring of capillary blood glucose in the unit were anti-HCV positive, compared to 4 (20%) of 20 who had not (relative risk, 5.0; 95% confidence interval, 2.1-12.0). Seventy (39.5%) of the patients with diabetes were screened for anti-HCV; 12 (18.8%) tested positive, with 3 (25%) positive for HCV-RNA. Patients with diabetes had routine capillary blood glucose monitoring while hospitalized and shared with CF patients the same spring-triggered devices for capillary blood glucose monitoring. The disposable platform of the devices was not changed between patient use. All HCV isolates belonged to the type 1, subtype b, and phylogenetic analysis showed a close homology by sequencing of NS5b and E2/HVR regions.

As reported earlier for the hepatitis B virus, shared spring-triggered devices for capillary blood glucose monitoring by finger puncture may transmit HCV. Strict application of Standard Precautions procedures is warranted in any healthcare setting.

To determine the fraction of hospital deaths potentially associated with nosocomial infection (NI).

A matched (1:1) case-control study.

An 800-bed, tertiary-care, teaching hospital.

All patients older than 14 years who were admitted to the hospital between January 1, 1990, and January 1, 1991, were eligible. All 524 consecutive deaths that occurred in the hospital comprised the case group. For each case, a control patient was matched for primary admission diagnosis and admission date.

The proportion of hospital deaths potentially associated with NI was estimated from the population attributable risk (PAR) adjusted for age, gender, service, severity of illness, length of stay, and quality of the medical record.

For stays longer than 48 hours, the PAR for all NIs was estimated to be 21.3% (95% confidence interval [CI95], 16.8%-30.5%). The greatest proportion of deaths potentially associated with NIs was observed in patients with only one infection (PAR, 15.0%; CI96, 10.9%-22.6%) and bacteremia or sepsis (PAR, 7.7%;CI95,4.6%-11.6%).

NIs are associated with a large proportion of intrahospital deaths. This information may help clinicians and healthcare managers to assess the impact of programs for the prevention and control of NIs on intrahospital death.