Bioterrorism is the deliberate release of viruses , bacteria , or other germs ( agents ) used to cause illness or death in people , animals , or plants . Biological agents are typically found in nature , but it is possible that they can be changed to increase their ability to cause disease , make them resident to current medicines , or to increase their ability to be spread into the environment . Biological agents in the hands of terrorists pose serious threats to states ’ security because they can be easily spread through the air , through water , and through food . Biological agents can also be difficult to detect and often do not cause illness for several hours to several days . A prominent example of a bioterrorist attack on the United States is the September 2001 anthrax attacks . On September 18 , 2001 , several letters containing anthrax were sent to media outlets and the U.S. Congressional offices of Senator Thomas Daschle and Senator Patrick Leahy . Five Americans died from anthrax inhalation as a result of contact with the contaminated mail . While the 2001 anthrax attacks were relatively small-scale , the United States government has taken several steps since to 2001 to pass legislation and initiatives aimed at better protecting the United States against biological attacks , improving the United States ’ public health system , and improving the United States ability to respond to biological attacks
2001 anthrax attacks
2001 anthrax attacks
Tactics of terrorism