Informatics and epidemiology in infection control.

Increasing amounts of hospital data are available electronically and offer new possibilities in performing surveillance for health care-associated infections. To use electronic information effectively, health care epidemiologists need to be aware of potential sources of data, issues with data integrity, and the trade-offs in using electronic data for surveillance as opposed to traditional manual surveillance. In reality, a combined surveillance approach may provide the best possible result. A clear understanding of the epidemiologic principles, such as prevalence and incidence, and some of the nuances behind these principles are essential for the proper interpretation of the epidemiologic data.