SUB-PROBLEMS INCLUDING LEADING TO IMPAIRMENT AND BEST PRACTICES FOR BIOTERRORISM AND POTENTIAL AGENTS
(See endnote 36)
Note: Only those agents listed in Category A will be discussed and the rest of the section will be about the CDC Office of Public Health Preparedness and Response which is responsible for providing the necessary research and resources for the control of bioterrorism in the United States.
Bioterrorism is the deliberate release of viruses, bacteria, or other microorganisms to cause illness or death in people or animals, or destroy plant life which may be used as a food source. These microorganisms already exist and can cause disease, but by increasing their quantity and altering certain parts of the organism, terrorists can make the attack extremely deadly and cause considerable destruction, death, and fear in a population. These agents, which are very stable in the environment, can be spread through air, water, or food and may be very difficult to detect until a disease outbreak occurs. The organisms in the case of smallpox and pneumonic plague could then be spread further from person to person.
Although the bacteria or toxins from a biological terrorist attack can enter the body many times by all potential routes including inhalation, ingestion, absorption through the skin or eyes, and arthropod-borne transmission from animals or other humans, the inhalation route for many organisms is the most common. The aerosols may contain Burkholderia pseudomallei, Burkholderia maiiei, Coxiella burnetii, the causative agent of Q fever, and select other Rickettsia, all of which can be inhaled and cause human disease, and some of which have a mortality rate of 50% and cause severe or chronic disease even if treated with antibiotics.
Arthropod-borne viruses that can be used as a biological weapons include the alphaviruses that are the cause of Venezuela equine encephalitis, Eastern equine encephalitis, and Western equine encephalitis; flaviviruses that are the cause of West Nile virus disease, Japanese encephalitis, Kyasanur Forest disease, tick-borne encephalitis, and yellow fever; and Bunyaviruses that are the causes of California encephalitis, La Cross virus diseases, and Crimean-Congo hemorrhagic fever.
Food- and waterborne viruses include hepatitis A virus and the caliciviruses, most notably Norwalk. They are excellent for bioterrorist threats because they can spread rapidly and are highly infective.
Hepatitis A virus causes about 55% of the cases of hepatitis in the United States each year. Transmission can be by water and food or directly from person to person. Norwalk virus and other caliciviruses cause a diarrheal disease which has been very prominent in outbreaks in camps, hospitals, nursing homes, and cruise ships. They cause about one third of the viral diarrheal diseases in the United States. Enteric protozoa such as Entamoeba histolytica, T. gondii, Giardia lamblia, Cryptosporidium parvum, etc. can also be disseminated by terrorists in food or water. In all food and water contamination, those at greatest risk are the very young, very old, immunocompromised, and those with debilitating acute or chronic diseases.
Toxins which can be utilized in bioweapons which include those from C. perfringens, Staphylococcal enterotoxin B and Clostridium botulinum can be delivered in air, food, or water. Ricin toxin comes from the castor plant. C. botulinum is heat stable and available throughout the world. The toxin prevents protein synthesis and leads to cell death.
Categories of Potential Organisms Used as Bioweapons
The CDC has established three categories of organisms. These categories are as follows:
- • Category A which includes organisms or toxins that are of the greatest risk to the public and national security because they: can be spread easily from person to person; cause high death rates; cause panic and disruption of society; and require special precautions by public health officials.
- • Category B which holds second priority and includes organisms that spread easily, cause moderate illness and few deaths, and require special CDC laboratory capacity. (See endnote 36 for a list of diseases.)
- • Category C which includes emerging pathogens that have been bioengineered to spread in the future, are readily available, are easily produced and spread, and have potential for high morbidity and mortality. (See endnote 36 for a list of diseases.)