Chapter 125. Health Care– Associated Infections (Part 2) Organization, Responsibilities, and Increasing Scrutiny of Infection- Control Programs The standards of the Joint Commission on Accreditation of Healthcare Organizations require all accredited hospitals to have an active program for surveillance, prevention, and control of nosocomial infections. Education of physicians in infection control and health care epidemiology is required in infectious disease fellowship programs and is available by online courses. Diagnosis-related reimbursement has led hospital administrators to place increased emphasis on infection control. Federal concerns over "patient safety" have led to legislation that would limit reimbursement for hospital costs resulting from at least two (yet-to-be-determined) nosocomial infections. The patient safety movement has prompted major national efforts to improve, measure, and publicly report on processes of patient care (e.g., timely administration and appropriateness of perioperative antibiotic prophylaxis) and patient outcomes (e.g., surgical wound infection rates). Surveillance Traditionally, infection-control practitioners have surveyed inpatients for infections acquired in hospitals (defined as those neither present nor incubating at the time of admission). Surveillance involves review of microbiology laboratory results, "shoe-leather" epidemiology on nursing wards, and application of standardized definitions of infection. Some infection-control programs use computerized hospital databases for algorithm-driven electronic surveillance (e.g., of vascular catheter and surgical wound infections). Commercial health care information systems that facilitate these functions are considered "value-added" products. Most hospitals aim surveillance at infections associated with a high level of morbidity or expense. Quality-improvement activities in infection control have led to increased surveillance of personnel compliance with infection-control policies (e.g., adherence to influenza vaccination recommendations). The growing number of states that require public reporting of processes for prevention of health care– associated infection and/or patient outcomes has added new complexity to what hospitals measure and how they measure it. Results of surveillance are expressed as rates. In general, 5–10% of patients develop nosocomial infections—a rate that, as patient advocates emphasize, has remained unchanged for 20–30 years. However, such broad statistics have little value unless qualified by duration of risk, by site of infection, by patient population, and by exposure to risk factors. Meaningful denominators for infection rates include the number of patients exposed to a specific risk (e.g., patients using mechanical ventilators) or the number of intervention days (e.g., 1000 patient-days on a ventilator). Temporal trends in rates should be reviewed, and rates should be compared with regional and national benchmarks. However, even comparison rates generated by the National Healthcare Safety Network (NHSN) have not been validated independently and represent a nonrandom sample of hospitals. [NHSN is the successor to the National Nosocomial Infections Surveillance System, a program of the Centers for Disease Control and Prevention (CDC) that collected data from more than 350 hospitals that use standardized definitions of nosocomial infections.] Interhospital comparisons may be misleading because of the wide range in risk factors and severity of underlying illnesses. Although systems for making adjustments for these factors either are rudimentary or have not been well validated, process measures (e.g., adherence to hand hygiene) do not usually require risk adjustment, and outcome measures (e.g., cardiac surgery wound infection rates) can identify hospitals with higher infection rates (e.g., in the top quartile) for further evaluation. Moreover, temporal analysis of an individual hospital's process and infection outcome rates helps to determine whether control measures are succeeding and where increased efforts should be focused. Epidemiologic Basis and General Measures for Prevention and Control Nosocomial infections follow basic epidemiologic patterns that can help to direct prevention and control measures. Nosocomial pathogens have reservoirs, are transmitted by predictable routes, and require susceptible hosts. Reservoirs and sources exist in the inanimate environment (e.g., tap water contaminated with Legionella) and in the animate environment (e.g., infected or colonized health care workers, patients, and hospital visitors). The mode of transmission usually is either cross-infection (e.g., indirect spread of pathogens from one patient to another on the inadequately cleaned hands of hospital personnel) or autoinoculation (e.g., aspiration of oropharyngeal flora into the lung along an endotracheal tube). Occasionally, pathogens (e.g., group A streptococci and many respiratory viruses) are spread from person to person via infectious droplets released by coughing or sneezing. Much less common—but often devastating in terms of epidemic risk—is true airborne spread of droplet nuclei (as in nosocomial chickenpox) or common- source spread by contaminated materials (e.g., contaminated intravenous fluids). Factors that increase host susceptibility include underlying conditions and the many medical-surgical interventions and procedures that bypass or compromise normal host defenses. Through their programs, hospitals' infection-control committees must determine general and specific control measures. Given the prominence of cross- infection, hand hygiene is the single most important preventive measure in hospitals. Health care workers' rates of adherence to hand-hygiene recommendations are abysmally low (<50%). Reasons cited include inconvenience, time pressures, and skin damage from frequent washing. Sinkless alcohol rubs are quick and highly effective and actually improve hand condition since they contain emollients and allow the retention of natural protective oils that would be removed with repeated rinsing. Use of alcohol hand rubs between patient contacts is now recommended for all health care workers except when the hands are visibly soiled, in which case washing with soap and water is still required. . Chapter 125. Health Care– Associated Infections (Part 2) Organization, Responsibilities, and Increasing Scrutiny of Infection- Control Programs The standards of the Joint. reporting of processes for prevention of health care– associated infection and/ or patient outcomes has added new complexity to what hospitals measure and how they measure it. Results of surveillance. independently and represent a nonrandom sample of hospitals. [NHSN is the successor to the National Nosocomial Infections Surveillance System, a program of the Centers for Disease Control and Prevention