Objective: To determine trends in rates of nosocomial infections in Spanish hospitals.

Design: Prospective prevalence studies, performed yearly from 1990 through 1994.

Setting: A convenience sample of acute-care Spanish hospitals.

Participants and Patients: The number of hospitals and patients included were as follows: 1990, 125 hospitals and 38,489 patients; 1991, 136 and 42,185; 1992, 163 and 44,343; 1993, 171 and 46,983; 1994, 186 and 49,689. A core sample of 74 hospitals, which participated in all five surveys and included a mean of 23,871 patients per year, was analyzed separately.

Results: The overall prevalence rate of patients with nosocomial infections in the five studies was as follows: 1990, 8.5%; 1991, 7.8%; 1992, 7.3%; 1993, 7.1%; and 1994, 7.2%. The prevalence rate of patients with nosocomial infection in the core sample of 74 hospitals was 8.9%, 8.0%, 7.4%, 7.6%, and 7.6%, respectively (test for trend, P=.0001). Patients admitted to intensive care units had a 22.8% prevalence rate of nosocomial infection in 1994. The most common nosocomial infections by primary site were urinary tract infection and surgical site infections, followed by respiratory tract infections and bacteremia. More than 60% of all infections were supported by a microbiological diagnosis.

Conclusions: The EPINE project provides a uniform tool for performing limited surveillance of nosocomial infections in most Spanish acute-care hospitals. Its use helps to spread an accepted set of definitions and methods for nosocomial infection control in the Spanish healthcare system. The surveys indicate that the prevalence of nosocomial infections has been reduced over the last 5 years in a core sample of Spanish hospitals.

Background: Methicillin-resistant Staphylococcus aureus (MRSA) is an escalating problem in hospitals worldwide. The hospital reservoir for MRSA includes recognized and unrecognized colonized or infected patients, as well as previously colonized or infected patients readmitted to the hospital. Early and appropriate infection control measures (ICM) are key elements to reduce MRSA transmission and to control the hospital reservoir.

Objective: To describe the role of an expert system applied to the control of MRSA at a large medical center (1,600 beds) with high endemic rates.

Methods: The University Hospital of Geneva has an extended hospital information system (HIS), DIOGENE, structured with an open distributed architecture. It includes administrative, medical, nursing, and laboratory applications with their relational databases. Among available patient databases, clinical microbiology laboratory and admission-discharge-transfer (ADT) databases are used to generate computer alerts. A laboratory alert (lab alert) is printed daily in the Infection Control Program (ICP) offices, listing all patients with cultures positive for MRSA detected within the preceding 24 hours. Patients might be either newly detected patients colonized or infected with MRSA, or previously recognized MRSA patients having surveillance cultures. The ICP nurses subsequently go to the ward or call the ward personnel to implement ICM. A second alert, the “readmission alert,” detects readmission to the hospital of any patient previously colonized or infected with MRSA by periodic queries (q 1 min) to the ADT database. The readmission alert is printed in the ICP offices, but also forwarded with added guidelines to the emergency room.

Results: During the first 12 months of application (July 1994 to June 1995), the lab alert detected an average of 4.6 isolates per day, corresponding to 314 hospital admissions (248 patients); the use of this alert saved time for the ICP nurses by improving work organization. There were 438 readmission alerts (1.2 alerts per day) over the study period; of 347 patients screened immediately upon readmission, 114 (33%) were positive for MRSA carriage. Delayed recognition of readmitted MRSA carriers decreased significantly after the implementation of this alert; the proportion of MRSA patients recognized at the time of admission to the hospital increased from 13% in 1993 to 40% in 1995 (P<.001).

Conclusions: Hospital information system-based alerts can play an important role in the surveillance and early prevention of MRSA transmission, and it can help to recognize patterns of colonization and transmission.

This article describes ethical dilemmas faced routinely by infection control personnel and outlines the basic principles of ethics as applied to the practice of infection control and hospital epidemiology.

Among 89 episodes of Staphylococcus aureus bacteremia, factors identified as independent predictors of hospital mortality were Acute Physiology and Chronic Health Evaluation III score >60 (odds ratio [OR], 3.2; 95% confidence inter val [CI95], 1.7 to 5.9) and Lifestyle score >1 (OR, 2.1; CI95, 1.2 to 3.6). Future studies of S aureus bacteremia should take into consideration acute severity of illness (as well as treatment and source of infection) when evaluating outcome.

Two hundred seventy-five of 325 (85%) healthcare workers (HCWs) completed a questionnaire testing their knowledge of transmission of tuberculosis (TB) and infection control measures for TB. Of the 75 HCWs with no patient contact, 49 (65%) felt that masks should be worn, and 40 (53%) would use gowns. In contrast, 175 (88%) of 200 HCWs having contact with patients thought masks should be worn, and 70 (35%) would use gowns (P=.0001 and .0085, respectively). Only 87% of HCWs with patient contact felt that respiratory precautions should be instituted for TB patients. The results of our sur vey showed that HCWs should be reeducated about TB.

Organisms living on our external and internal body surfaces are the first contact for many potentially pathogenic invaders. Factors that alter this microenvironment include antibiotics, the host immunity, and the various diseases of man and their treatment. Predicting when colonization leads to infection remains an important challenge for every clinician. The maintenance and breakdown of colonization resistance by changes in the native microflora and the body's natural mucosal coating by various extrinsic and intrinsic factors is reviewed in this article. Quantitative culture methods developed to improve the predictive value of a given sampling technique (most notably with bronchoscopy) is presented. Besides improving diagnostic capabilities, quantitative cultures can be used successfully as an epidemiologic tool for some outbreak investigations.

The laboratory plays a major role in the epidemiology program's efforts to minimize nosocomial infections in healthcare institutions. This article will describe some of the interactions between the laboratory and the epidemiology program, and will identify resources and procedures that the laboratory needs to achieve epidemiologic goals.