Infection Control Epidemiology and Clinical Microbiology

Abstract

This chapter discusses the impact of nosocomial infections, outlines the organization of the hospital infection control program, and describes the important role of the clinical microbiology laboratory in the prevention and control of health care-associated infections. The Study of the Efficacy of Nosocomial Infection Control indicated that the presence of an active surveillance and infection control program was associated with a 32% decrease in nosocomial infection rates while the absence of such a program was associated with an 18% increase in nosocomial infection rate. The hospital infection control program should include surveillance and prevention of nosocomial infections. The chapter focuses on the most important specific roles played by a microbiology laboratory in the day-to-day practice of infection control. Commercial identification and susceptibility testing systems allow most laboratories to identify microorganisms to species level and perform antimicrobial susceptibility testing (AST). However, the expanding spectrum of organisms that colonize and infect seriously ill patients challenges the ability of a clinical microbiology laboratory to identify and characterize nosocomial pathogens accurately. When the infection control team detects a cluster or outbreak of nosocomial infection, they must act promptly to identify the etiologic agent if it is not known, define the extent of the outbreak, learn the mode of transmission for the pathogen, and institute appropriate control measures. Development and application of new technologies in the clinical laboratory can greatly enhance infection control efforts.