Q: Given a scientific passage and an answer, generate a question for the given answer.
Passage: Bioterrorism is the intentional release or spread of agents of disease. The agents may be viruses, bacteria, or toxins produced by bacteria. The agents may spread through the air, food, or water; or they may come into direct contact with the skin. Two of the best known bioterrorism incidents in the U. S. occurred early in this century:. Answer: bioterrorism
A:
The intentional release or spread of agents of disease is known as what?