Question

What is the difference between an outbreak and an epidemic and how would investigations differ?

Answer 1

An outbreak is a sudden rise in the number of cases of a disease . It may occur in a community or geographical area or may affect several countries and last for a few days or weeks ,or several years .

An epidemic occurs when infectious disease spreads quickly   to many individuals at the same time.

Epidemic / outbreak investigation is a set of procedures used to identify the cause , ie, the infectious agent , responsible for the disease and to identify the people affected, the circumstances and mode of transmission of the disease and the other relevant factors.  

Both outbreak investigation and epidemic investigation are same.