Programs that protect the public health through comprehensive efforts to track the incidence and distribution of disease in the population and prevent, control and eradicate vaccine-preventable diseases, vector and food-borne illnesses, diseases that are transmitted person-to-person and other diseases that are spread by direct or indirect contact. Activities include routine surveillance of communicable disease activity, assessment of the community immunization level through school records and immunization studies, investigation of epidemic outbreaks, reporting of cases of infectious diseases to the proper authorities and taking appropriate measures such as isolation and contact tracing/notification to prevent disease transmission.