Prepare for field work
Establish the existence of an outbreak
Verify the diagnosis
Construct a working case definition
Find cases systematically and record information
Perform descriptive epidemiology
Develop hypotheses
Evaluate hypotheses epidemiologically
As necessary, reconsider, refine, and re-evaluate hypotheses
Compare and reconcile with laboratory and/or environmental studies
Implement control and prevention measures
Initiate or maintain surveillance
Communicate findings