Bioterrorism
There are three categories of biological agents. The first is category A, the highest priority agents. Biological agents in category A pose a high risk to national security. These include anthrax and smallpox. The second, category B, includes biological agents such as brucellosis and melioidosis. These are a risk to national security. Category C, the third, includes emerging diseases that could be a risk in the future, such as hantavirus.