Hospital Surveillance Systems help to identify local problems and priorities and to evaluate the effectiveness of infection control activities. Surveillance systems need to evolve with changes in health care systems. An active, reliable, time-efficient system is needed, which is based on standard definitions. Electronic systems have revolutionized the concept of surveillance, facilitating automatic tracking, feeding back information to central agencies and analyzing data from multiple hospitals using standard definitions.

In the absence of standard diagnostic definitions, infections like ventilator associated pneumonia, urinary tract infections and catheter - related blood stream infections may be grossly over-diagnosed, prompting injudicious use of antimicrobials, in turn promoting drug resistance, and thereby tremendously escalating the cost of treatment.