Table 1.

Purposes and uses of public health surveillance

Estimating the magnitude of a public health problem and predicting future trends

Determining the geographic distribution of an illness

Portraying the natural history of a disease

Detecting epidemics or defining a problem

Generating hypotheses and stimulating research

Evaluating and instituting control measures

Monitoring changes in infectious agents (e.g., development of antibiotic resistance)

Identifying individual cases for treatment of a communicable disease

Tracking contacts for prophylactic therapy or other preventive measures

Detecting changes in health practices

Facilitating planning