Final answer:
Epidemiology is the study of disease frequency and distribution to identify risk factors and set prevention guidelines. It helps in understanding how diseases occur and spread within human populations and environments. Epidemiologists collect data, track transmission, and develop strategies to reduce disease incidence.
Step-by-step explanation:
Epidemiology is the study of the frequency and distribution of disease in order to identify risk factors and set guidelines for the prevention and control of certain diseases. It is a branch of public health that focuses on understanding how diseases occur and spread within human populations and environments. Epidemiologists collect data, track disease transmission, and use the information to develop strategies and public health policies to reduce disease incidence and prevent its spread.