Different types of surveillance systems are used by public health experts to promote health and prevent diseases. These systems can be used to track disease trends and develop public health initiatives. Disease surveillance can be divided into two categories โ€“ passive and active. Passive The reporting of passive disease surveillance to state or local officials begins with healthcare providers or laboratories. On a case-by-case basis , based on a published list of conditions, reportable diseases are submitted. Active When the state or local officials conduct active disease surveillance , they contact healthcare providers, laboratories, schools, nursing homes, and workplaces to gather information.

Question: Which type of surveillance includes calling providers to detect smallpox-related adverse events? A. Passive B. Active C. Sentinel D. None of the above