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Biosafety Levels • Do not usually cause disease minimal
safety equipment • Usually those found in high
school/college student labs • Example: Bacillus subtilis
BSL-1 • Known to cause human disease • Encompasses most clinical hospital
laboratories • Ex. HBV and salmonellae
BSL-2 • Known to produce serious disease • Transmitted by respiratory route
• Not identifying directly from specimens(BSL-2) but culturing M. tuberculosis
BSL-3 • Require containment suits • High risk of serious disease • No available treatment
• Ebola BSL-4
Public Health Preparedness
Three categories Category A
• Greatest impact Anthrax, hemorrhagic fevers
Category B Salmonella, ricin, E.coli O157:H7
Category C • Less impact
MDR-TB, hantavirus
See Table 30-1 for full list of examples
Key Indicators of a Potential Bioterror or Biocrime Event
General Characteristics of Bioterror Agents
Easily made Low skill required
Mobile Easy to transport
Transmission Aerosol Person-to-person spread Resistant to decay
History of Criminal Use of Microbial Agents
Salmonella Sprayed onto salad bars in restaurants
Anthrax spores Contaminated letters in NY, DC, and Florida
Ricin toxin
Laboratory Response Network (LRN)
Established in 1999 Community hospitals with microbiology
capabilities Sentinel laboratories
• Must have BSL-2 capabilities Five agents with protocols
– B. anthracis – Y. pestis – F. tularensis – Brucella spp. – Etc.
Laboratory Response Network (LRN) Reference laboratories
Perform confirmatory tests on several biothreat agents
• State public health laboratories • Department of defense medical center laboratories
National laboratories Can perform complex forensic studies Definitive characterization of biothreat agents
• CDC • USAMRIID • National Research Medical Center
Structure of the Laboratory Response Network
Agents of Bioterror
Bacillus anthracis Cutaneous anthrax
• Very few cases Black eschar on skin
Gastrointestinal anthrax • Ingestion of spores in contaminated
food Inhalation anthrax
• Generally none unless bioterror or lab accident
Agents of Bioterror Specimen collection
Swabs from black eschar Blood sample from inhalation and gastrointestinal
anthrax • Colonies have medusa-head morphology
Nonhemolytic
Morphology of Anthrax on Blood Agar, Gram Stain, and Spore Stain
13 Elsevier items and derived items © 2011, 2007 by Saunders, an imprint of Elsevier Inc.
Agents of Bioterror Yersinia pestis
“Black death” Linked to bubonic plague in 1894
• Major vector is flea
Agents of Bioterror
Transmission Bite of infected fleas Handling contaminated materials Inhaling aerosolized bacteria
Weaponized Y. pestis Primarily pneumonic plague
• Person-to-person transmission
Agents of Bioterror
Symptoms Fever, chills, headache, malaise Buboes
• Inflammation of the lymph node causing swelling Bacteria disseminate and cause DIC
– Results in gangrene in fingers and nose
Agents of Bioterror
Direct examination and culture Plump gram-negative rods Bipolar staining
• Safety pin appearance
Agents of Bioterror
Francisella tularensis BSL-3 pathogen Zoonotic disease Infectious dose
• As low as 10 organisms
Ulceroglandular tularemia Skin infection
• Bite of infected insect • Handling infectious materials
Cutaneous Lesions
Agents of Bioterror
Clinical manifestations Symptoms
• Fever with chills • Headaches • Cough • Chest pain • Lesions at site of entry
Occasionally respiratory disease
Agents of Bioterror Brucella spp.
Small gram-negative pleomorphic aerobic coccobacilli
• Brucella melitensis • Brucella suis • Brucella abortus
Mostly eliminated in the United States • BSL-3 containment required
Transmission • Breaks in skin • Ingestion of food products • Aerosols in laboratory conditions
Agents of Bioterror (Cont’d)
Symptoms Malaise, night sweats, relapsing fever, chills,
myalgia • Requires 5-35 days of incubation before symptoms
Can persist for months Most recover without treatment
Previous use as a biologic weapon
Agents of Bioterror (Cont’d)
Burkholderia species B. mallei
• Glanders B. pseudomallei
• Melioidosis Symptoms
• Fever, myalgia, headache, and chest pain Caused by cutaneous lesions, bloodstream infections,
pneumonia
Agents of Bioterror (Cont’d)
Coxiella burnetii Causative agent of Q fever (Query fever) Reservoirs
• Cattle, sheep, goats, dogs, cats, deer, fowl, and humans • Exposure in vet or animal handlers
Transmission • Urine, milk, feces, tissues, and fluids expelled during
birth • Incubation period 2-3 weeks
Agents of Bioterror
Smallpox Two major forms
• Variola major 30% mortality in unvaccinated 3% in vaccinated
• Variola minor Similar but much less severe disease
Smallpox Pustules
Agents of Bioterror
Viral hemorrhagic fevers Ebola, Marburg, Lassa fever, Crimean-Congo, Rift
Valley fever, Hantavirus Transmission
Direct contact Urine, semen
Agents of Bioterror (Cont’d)
Clinical manifestations Incubation period 2 to 3 weeks Fever, rash, myalgia, arthralgia, nausea,
conjunctivitis, diarrhea, and CNS symptoms Bleeding, DIC, hemorrhage of mucous
membranes • Some have high mortality rates
Agents of Bioterror
Toxins Clostridium botulinum toxin Staphylococcal enterotoxins Ricin
• Contamination of food or water sources