Veterinary Information Alert - Bioterrorism Involving Livestock

In light of the recent events in North America, governments and the public have a heightened awareness and concern about the possibility of bioterrorism involving agriculture, including livestock. This alert is not meant to cause panic or overstate the obvious. However, veterinarians and livestock owners may be the first to diagnose the early cases of a bioterrorist act in agriculture, as livestock can be sentinels of such an exposure. At the very least this note provides further points of contact for more information.

The Centers for Disease Control and Prevention in the United States has produced a list of the most likely biological agents to be used in an act of bioterrorism (see excerpt below). Many of these are pathogens shared by humans and animals, and some have agricultural significance. Other agents of concern include Foreign Animal Diseases and other reportable diseases (such as Foot and Mouth Disease, Avian Influenza). Although many of the pathogens listed as possible bioterrorism agents would cause localised or sporadic disease, some may have serious public health or trade implications.

Veterinarians should remain current and vigilant for clinical signs consistent with any reportable or foreign animal disease, as well as unusual patterns or clusters of disease from the agents listed below. The Animal Health Laboratory (University of Guelph) and other diagnostic laboratories across Canada have been notified to be on alert for the detection of such agents. Diseases or clusters that might point to an exposure consistent with an act of bioterrorism could include: unusual demographic patterns, multiple species involvement, concurrent animal/public health problems, and unusual clusters of strains or serotypes. Points of contact for animal health information are listed below.

Foreign Animal Disease Emergency Number for veterinarians - 1 877 814 2342
CFIA Ontario Region - 519 837 9400 or your local area office
Dr. Grant Maxie, AHL University of Guelph - 519 824 4120 x4544
Agricultural Information Contact Centre, OMAFRA - 1 877 424 1300

Centers for Disease Control and Prevention - Critical Biological Agents

Category A

The U.S. public health system and primary health-care providers must be prepared to address varied biological agents, including pathogens that are rarely seen in the United States. High-priority agents include organisms that pose a risk to national security because they:

• can be easily disseminated or transmitted person-to-person;
• cause high mortality, with potential for major public health impact;
• might cause public panic and social disruption; and
• require special action for public health preparedness

Category A agents include:

• variola major (smallpox);
• Bacillus anthracis (anthrax);
• Yersinia pestis (plague);
• Clostridium botulinum toxin (botulism);
• Francisella tularensis (tularaemia);
• Filoviruses (e.g. Ebola hemorrhagic fever, Marburg hemorrhagic fever);
• Arenaviruses (e.g. Lassa (Lassa fever), Junin (Argentine hemorrhagic fever))
  

Category B

Second highest priority agents include those that:

• are moderately easy to disseminate;
• cause moderate morbidity and low mortality; and
• require specific enhancements of CDC's diagnostic capacity and enhanced disease surveillance.
  

Category B agents include:

• Coxiella burnetti (Q fever);
• Brucella species (brucellosis);
• Burkholderia mallei (glanders);
• Alphaviruses (e.g. Venezuelan encephalomyelitis, eastren and westren equine encephalomyelitis);
• Venezuelan encephalomyelitis;
• ricin toxin from Ricinus communis (castor beans);
• epsilon toxin of Clostridium perfringens;
• Staphylococcus enterotoxin B;
• Chlamydia psittaci (Psittacosis)

A subset of List B agents includes pathogens that are food or waterborne. These pathogens include but are not limited to:

• Salmonella species;
• Shigella dysenteriae;
• Escherichia coli O157:H7;
• Vibrio cholerae; and
• Cryptosporidium parvum.
  

Category C

Third highest priority agents include emerging pathogens that could be engineered for mass dissemination in the future because of:

• availability;
• ease of production and dissemination; and
• potential for high morbidity and mortality and major health impact.

Category C agents include:

• Nipah virus;
• hantaviruses;
• tickborne hemorrhagic fever viruses;
• tickborne encephalitis viruses;
• yellow fever; and
• multidrug-resistant tuberculosis.

(Adapted from: Biological and Chemical Terrorism: Strategic Plan for Preparedness and Response. Centers for Disease Control and Prevention, April 21 2000; 49(RR04): 1-14)

Related Links:

• Health Canada: Information on biological agents
  
• US Centers for Disease Control and Prevention
  
• CFIA information on anthrax