Etiologic agents
                                            CENTERS FOR DISEASE CONTROL AND PREVENTION
Etiologic agents are those microorganisms and microbial toxins that cause disease in humans and include bacteria,
bacterial toxins, viruses, fungi, rickettsiae, protozoans, and parasites. These disease-causing microorganisms may also
be referred to as infectious agents. Arthropods and other organisms that transmit pathogens to animals (including
humans) are called vectors.

Etiologic agents, vectors, and materials containing etiologic agents are recognized as hazardous materials. Materials
containing etiologic agents are regularly transported from one location to another by common land and air carriers.
Materials containing etiologic agents must be appropriately packaged to prevent breakage or leakage in order to avoid
exposure of the package handlers, transporters, and the general public to the package contents. Materials containing
etiologic agents must be packaged, labeled, and transported in accordance with all applicable regulations. Material
containing etiologic agents being imported into the United States must be accompanied by a U.S. Public Health Service
importation permit.