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Bioterrorism Information


Bioterrorism is defined as the use of living organisms or their products to produce death or disease in humans, animals or plants. Bioterrorism is sometimes grouped with nuclear and chemical terrorism and referred to collectively as NBC (nuclear, biological, chemical) or weapons of mass destruction (WMD).

The Centers for Disease Control & Prevention (CDC) and other experts have identified microorganisms that could have potential as biological weapons. Many of these microorganisms are extremely rare causes of disease, essentially nonexistent in the United States, or, in the case of smallpox, have been eradicated. In addition, some organisms or their toxins could be used in an airborne form, resulting in a different clinical presentation than with naturally acquired infection. Most physicians in this country have little or no familiarity with these organisms and would be hard-pressed to make the correct diagnosis quickly.

Although the likelihood of a successful bioterrorist event in Orange County seems remote, some basic preparedness is reasonable, especially if it can be used to strengthen basic public health functions such as communicable disease monitoring and control. In addition, we encourage physicians to learn more about and participate in their hospital's disaster planning efforts. Orange County Emergency Medical Services (OCEMS) has provided materials on bioterrorism to emergency departments and held educational programs and disaster drills regarding terrorism. For more information, please contact OCEMS at (714) 834-3500.


For physicians, preparation for a bioterrorist event involves becoming familiar with the agents most likely to be used in a bioterrorist attack, the clinical syndromes they cause and how they are transmitted, as well as epidemiological clues suggestive of a bioterrorist attack.

The microorganisms experts think are most likely to be used in a bioterrorist attack and the diseases they cause are:



Bacillus anthracis Anthrax
Yersinia pestis Plague
Variola virus Smallpox
Clostridium botulinum (botulinum toxin) Botulism
Francisella tularensis Tularemia
Hemorrhagic fever viruses (Ebola, Marbourg, Lassa fever, Crimean-Congo fever, etc.) Hemorrhagic fever

Although many textbooks no longer include clinical information on smallpox, recent journal articles on this and other potential bioterrorism agents are available (see reference list below).

CDC maintains a supply of smallpox vaccine, which is supplied only to certain laboratory workers who are at risk of infection with smallpox-like viruses as a result of their occupation. CDC has contracted for production of 40 million doses of smallpox vaccine. These supplies would be available in the event of a smallpox release.

Anthrax vaccine is available only for members of the military. The vaccine is not recommended for the general population, and there have been some difficulties in its manufacture. There are no safety data for persons less than 18 or older than 65 years of age. It is likely that the federal government would make anthrax vaccine available if a release occurred.


Epidemiological clues can suggest a biological attack; however, none of these is proof that a biological attack occurred. The epidemiological clues include the following.

  • Large numbers of cases of unexplained diseases or deaths
  • Higher morbidity and mortality in association with a common disease or syndrome, or failure of such patients to respond to usual therapy
  • Many ill persons seeking treatment at about the same time
  • Illness associated with a ventilation system
  • A disease that is unusual for a given geographic area, occurs outside the normal transmission season, or occurs in the absence of the normal vector for transmission
  • Multiple simultaneous epidemics of different diseases
  • Illness that is unusual (or atypical) for a given population or age group
  • Unusual patterns of death or illness among animals that precedes or accompanies illness or death in humans

Whether or not you suspect bioterrorism, any one of the factors listed above should prompt a call to Orange County Public Health. Unusual diseases and outbreaks, along with many other diseases, are reportable under California Code of Regulations, Title 17, Section 2500. A list of reportable diseases is available at:

Reports can be made by:

Telephone: Monday - Friday, 8:00 am to 5:00 pm: (714) 834-8180 or Fax: (714) 834-8196

After hours, weekends and holidays telephone (Sheriff Communications): (714) 628-7008

For your convenience, a form for reporting can be downloaded here.


The most critical step in response is early recognition that something unusual is occurring and notification of the Orange County Health Care Agency (the health department). The health department will notify and activate all other government agencies that would be involved in responding to a bioterrorist event. In such an event, the Orange County Health Care Agency will be responsible for:

  • Case investigation and case finding
  • Establishing a diagnosis
  • Notifying:
    • California Dept of Health Services
    • Centers for Disease Control & Prevention (CDC)
  • FBI and local law enforcement
  • Recommending treatment and infection control measures. Please note that treatment recommendations made in response to a bioterrorist event may differ from published recommendations due to the circumstances-antimicrobial resistance of the agent, availability of pharmaceuticals, etc.
  • Establishing exposure date(s) and location(s)
  • Identifying exposed persons
  • Following up cases and contacts
  • Providing mass prophylaxis (if indicated)

The response to a bioterrorist event will require the concerted effort of physicians, the health department, health care facilities, and many others to identify the biological agent involved, treat affected patients, prevent additional transmission, and bring the situation under control. Federal, state, and local governments and health departments are taking part in training to improve the ability to respond to a bioterrorist event. The federal government is stockpiling pharmaceuticals and other medical supplies that may be needed in large quantities following a bioterrorist event, and there are a variety of response teams that can be called upon for assistance. Local pharmaceutical and equipment stockpiling is being arranged. A regional system of laboratories with specialized tests for the agents listed above is being developed.

Management of the response will require your participation in rapid assessment of individual patients, collection of patient data, and dissemination of treatment protocols.