A bioterrorism attack is the deliberate release of bacteria, toxins and viruses, or other germs (agents) used to cause illness or death in people, animals, or plants. Typically found in nature, these agents are chemically changed to increase their ability to cause disease, make them resistant to current medicines, or to increase their ability to be spread into the environment.

Biological agents can be spread through the air, water, or food. Terrorists may use biological agents because they can be extremely difficult to detect and do not cause illness for several hours to several days. Some bioterrorism agents, like the smallpox virus, can be spread from person to person and some, like anthrax, cannot.  Please click on the links below for more specific information.


Bacteria are unicellular organisms. They vary in shape and size from spherical cells (cocci) to long rod-shaped organisms (bacilli).  The shape of the bacterial cell is determined by the rigid cell wall. The interior of the cell contains the nuclear material (DNA), cytoplasm, and cell membrane that are necessary for the life of the bacterium.  Under special circumstances some types of bacteria can transform into spores. The spore of the bacterial cell is more resistant to cold, heat, drying, chemicals and radiation than the vegetative bacterium itself. Spores are a dormant form of the bacterium and, like the seeds of plants; they can germinate when conditions are favorable.  Bacteria generally cause disease in human beings and animals by one of two mechanisms: by invading host tissues and/or by producing poisons (toxins).  Many pathogenic bacteria utilize both mechanisms.

Bacterial Threats Include:

Anthrax Botulism Brucellosis Pneumonic Plague Q-Fever Tularemia



Toxins are harmful substances produced by living organisms (animals, plants, microbes). Features that distinguish them from chemical agents, such as VX, cyanide, or mustard, include being not man-made, non-volatile (no vapor hazard), usually not dermally active (mycotoxins are the exception), and generally much more toxic per weight than chemical agents. Their lack of volatility is very important and makes them unlikely to produce either secondary or person-to-person exposures, or a persistent environmental hazard.


Viruses are the simplest microorganisms and consist of a nucleocapsid protein coat containing genetic material, either RNA or DNA. In some cases, an outer lipid layer also surrounds the viral particle. Viruses are much smaller than bacteria.  Viruses are intracellular parasites and lack a system for their own metabolism; therefore, they are dependent on the synthetic machinery of their host cells. This means that viruses, unlike the bacteria, require living cells in order to multiply.  The host cells can be from humans, animals, plants, or bacteria. Every virus requires its own special type of host cell for multiplication, because a complicated interaction occurs between the cell and virus.  A virus typically brings about changes in the host cell that eventually lead to cell death.


Anthrax is an acute infectious disease caused by the spore-forming bacterium Bacillus anthracis. Anthrax most commonly occurs in wild and domestic lower vertebrates (cattle, sheep, goats, camels, antelopes and other herbivores), but it also can occur in humans when they are exposed to infected animals or to tissue from infected animals or when anthrax spores are used as a bioterrorist weapon.

Anthrax Fact Sheet

Children and Anthrax: A fact Sheet for Parents

Suspicious Envelopes or Packages: What do I do? / Protocols

Anthrax Information for Prividors

Anthrax Lab Protocols


Botulism is a muscle-paralyzing disease caused by a toxin made by a bacterium called Clostridium botulinum.

There are three main kinds of botulism:

  • Food borne botulism occurs when a person ingests pre-formed toxin that leads to illness within a few hours to days. Food borne botulism is a public health emergency because the contaminated food may still be available to other persons besides the patient.

  • Infant botulism occurs in a small number of susceptible infants each year who harbor C. botulinum in their intestinal tract.
  • Wound botulism occurs when wounds are infected with C. botulinum that secretes the toxin.
Symptoms:    With food borne botulism, symptoms begin within 6 hours to 2 weeks (most commonly between 12 and 36 hours) after eating toxin-containing food. Symptoms of botulism include double vision, blurred vision, drooping eyelids, slurred speech, difficulty swallowing, dry mouth, muscle weakness that always descends through the body: first shoulders are affected, then upper arms, lower arms, thighs, calves, etc. Paralysis of breathing muscles can cause a person to stop breathing and die, unless assistance with breathing (mechanical ventilation) is provided.

Infection:  Botulism is not spread from one person to another. Food borne botulism can occur in all age groups.

Treatment:  A supply of antitoxin against botulism is maintained by CDC.  The antitoxin is effective in reducing the severity of symptoms if administered early in the course of the disease. Most patients eventually recover after weeks to months of supportive care. Botulism Frequently Asked Questions


Brucellosis is an infectious disease caused by the bacteria of the genus Brucella. These bacteria are primarily passed among animals, and they cause disease in many different vertebrates.  

Symptoms:  In humans brucellosis can cause a range of symptoms that are similar to the flu and may include fever, sweats, headaches, back pains, and physical weakness. Sever infections of the central nervous systems or lining of the heart may occur. Brucellosis cab also cause long-lasting or chronic symptoms that include recurrent fevers, joint pain, and fatigue.

Infection:  Humans are generally infected in one of three ways: eating or drinking something that is contaminated with Brucella, breathing in the organism (inhalation), or having the bacteria enter the body through skin wounds.  Direct person-to-person spread of brucellosis is extremely rare. Mothers who are breast-feeding may transmit the infection to their infants. Sexual transmission has also been reported.

Vaccination/Prophylaxis:  There is no vaccine available for humans.

Treatment:  Treatment for Brucellosis can be difficult. Doctors can prescribe effective antibiotics. Usually, doxycycline and rifampin are used in combination for 6 weeks to prevent reoccurring infection. Depending on the timing of treatment and severity of illness, recovery may take a few weeks to several months. Mortality is low (<2%), and is usually associated with endocarditis.

Pneumonic Plague

Pheumonic is an infectious disease of animals and humans caused by the bacterium Yersinia pestis. Y. pestis, is found in rodents and their fleas in many areas around the world. Symptoms:  Pneumonic plague occurs when Y. pestis infects the lungs.  The first signs of illness in pneumonic plague are fever, headache, weakness, and cough productive of bloody or watery sputum. The pneumonia progresses over 2 to 4 days and may cause septic shock and, without early treatment, death.

Infection:  Person-to-person transmission of pneumonic plague occurs through respiratory droplets, which can only infect those who have face-to-face contact with the ill patient.

Vaccination/Prophylaxis:  There is no vaccine against plague. Prophylactic antibiotic treatment for 7 days will protect persons who have had face-to-face contact with infected patients.

Treatment:  Early treatment of pneumonic plague is essential. Several antibiotics are effective, including streptomycin, tetracycline, and chloramphenicol.


Q-Fever is a zoonotic disease caused by Coxiella burnetii, a species of bacteria that is distributed globally.   Cattle, sheep, and goats are the primary reservoirs of C. burnetii.  These bacteria are able to survive for long periods in the environment. 

Infection:  Infection of humans usually occurs by inhalation of these organisms from air that contains airborne barnyard dust contaminated by dried placental material, birth fluids, and excreta of infected herd animals.  Humans are often very susceptible to the disease, and very few organisms may be required to cause infection.  Other modes of transmission to humans, including tick bites, ingestion of contaminated milk and human to human transmission, are rare.

Symptoms:  Most acute cases of Q fever begin with sudden onset of one or more of the following: high fevers (up to 104-105° F), severe headache, general malaise, myalgia, confusion, sore throat, chills, sweats, non-productive cough, nausea, vomiting, diarrhea, abdominal pain, and chest pain.  In general, most patients will recover to good health within several months without any treatment.  Chronic Q fever, characterized by infection that persists for more than 6 months is uncommon but is a much more serious disease. The incubation period for Q fever varies depending on the number of organisms that initially infect the patient. Most patients become ill within 2-3 weeks after exposure. Those who recover fully from infection may possess lifelong immunity against re-infection.

Treatment:  Doxycycline is the treatment of choice for acute Q fever. Antibiotic treatment is most effective when initiated within the first 3 days of illness.  Therapy should be started again if the disease relapses.

Vaccination/ Prophylaxis:  A vaccine for Q fever has been developed and has successfully protected humans in occupational settings in Australia. However, this vaccine is not commercially available in the United States.

Significance for Bioterrorism: Coxiella burnetii is a highly infectious agent that is rather resistant to heat and drying. It can become airborne and inhaled by humans. A single C. burnetii organism may cause disease in a susceptible person.  This agent could be developed for use in biological warfare and is considered a potential terrorist threat.


Tularemia is an infection caused by the organism Francisella tularensis, and is associated with both animals and man.  Infection:  Contraction of the infection can be from inoculation of the skin or mucous membranes from infected animals and from the bite of infected deer flies or ticks.  Areas where tularemia is endemic include parts of Asia and Europe as well as North America. 

Symptoms:  Symptoms usually begin with pneumonia like illness (fever, headache, chills and muscle pains) or if the organism is ingested may begin with vomiting, diarrhea and intestinal pain.

Vaccination/Prophylaxis:  People who spend a great deal of time outdoors or have occupational exposure risks are at greater risk of infection (hunters, laboratory workers, etc.).

Treatment:  Antibiotics such as streptomycin and tetracycline are effective in treating those infected with the organism.  Those who have been infected may possess life-long immunity.


Health Department Logo