Hospital-acquired pneumonia: perspectives for the healthcare epidemiologist.

Nosocomial pneumonia is defined as an infection of lung parenchyma that was neither present nor incubating at the time of the patient's admission to the hospital. In the United States, hospital-acquired pneumonia is the second most common nosocomial infection and accounts for the most deaths from nosocomial infection. We describe how infection control personnel can use targeted surveillance to identify clusters of cases and to prevent pneumonia. We also discuss common pathogens that cause nosocomial pneumonia; ventilator-associated pneumonia; and strategies for prevention of hospital-acquired pneumonia.