A food manufacturer or distributor discovers a food safety issue and contacts FDA or FSIS directly.
Inspection of a manufacturing facility or importer by FDA or FSIS reveals a potential cause for recall.
A food product or manufacturer fails testing carried out through FDA or FSIS sampling programs.
In the case of illness associated with a specific food product, individual state health departments will contact the Centers for Disease Control and Prevention (CDC), which in turn contacts FDA or FSIS.