Active surveillance in healthcare is a proactive approach to identifying and monitoring health-related events or diseases123. It involves the continuous, systematic collection, analysis, and interpretation of health-related data needed for the planning, implementation, and evaluation of public health practice1.

Option B, “Identifying disease outbreaks through public health contact tracing,” is an example of active surveillance. Contact tracing is a key strategy for preventing the further spread of infectious diseases. It involves identifying people who have an infectious disease (cases) and their contacts (people who may have been exposed) and working with them to interrupt disease transmission12.

Option A, “analyzing laboratory data for disease testing utilization,” could be part of both active and passive surveillance, depending on the context. However, it does not necessarily involve the proactive steps typically associated with active surveillance13.

Option C, “analyzing infectious diseases based on hospital discharge final coding,” is more related to passive surveillance, which involves the collection of data as they become available, or the data that are passively received by health care providers or health information systems13.

Option D, “reporting of infectious diseases data quarterly to local health departments,” is also more related to passive surveillance, as it involves regular reporting of health data from various sources13.