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BIOLOGICAL AGENTS. CDC has prioritized them in Lists A - C A List: Easily transmitted/disseminated High mortality rate Potential for public panic Public Health impact requiring preparedness. “A” LIST. Smallpox* Anthrax* Plague Botulism toxin Tularemia Viral Hemorrhagic Fevers*
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BIOLOGICAL AGENTS • CDC has prioritized them in Lists A - C • A List: • Easily transmitted/disseminated • High mortality rate • Potential for public panic • Public Health impact requiring preparedness
“A” LIST • Smallpox* • Anthrax* • Plague • Botulism toxin • Tularemia • Viral Hemorrhagic Fevers* • *person to person transmission possible
Anthrax: Overview • Primarily disease of animals who ingest anthrax spores from soil, (spores can last in soil for decades) • Natural transmission to humans by contact with infected animals or contaminated animal products • Cutaneous form most common form of anthrax (usually occupational); 224 cases in U.S. between 1944 – 1994 CDC: Gram stain of B. anthracis
Anthrax: Cutaneous Inoculation of spores under skin through cut/abrasion • Incubation: hours to 7 days (average 5 days) • Small bump (3 – 5 days) ulcer surrounded by blisters 24-28h later • Toxin production leads to local edema • Painless black scab over ulcer • Painful , swollen lymph nodes possible • Death 20% untreated; rare treated USAMRIID: Eschar with surrounding edema
Anthrax: Inhalational • Inhalation of spores, which then grow into bacteria • Incubation: 1 to 43 days • Initial symptoms (2-5 d) • fever, cough, myalgia, malaise • Terminal symptoms (1-2d ) • high fever, shortness of breath • Most of signs occur in lungs: swollen lymph nodes and fluid accumulation • rapid progression to shock / death because toxins released by the anthrax bacteria • Mortality rate ~100% despite aggressive Rx CDC: CXR with widened mediastinum of inhalational anthrax
Anthrax: Post-exposure Treatment • Ciprofloxacin or Doxycycline Antibiotics for 60 days without vaccine • Antibiotics for 30 days with 3 doses of vaccine (animal studies)
Antibiotic Adverse Effects • Cipro: Nausea, vomiting, abdominal pain, dizziness, headache, restlessness, confusion • Doxy: GI disturbances, diarrhea, teeth staining in children < 6 y/o • Compliance? • Between 25 – 75% of Washington D.C. postal workers in 2001 did not complete course because of side effects of antibiotics
Anthrax: Vaccine • FDA approved for persons 18-65 years of age • Not entirely sure how fully it protects against inhalational anthrax • Six shots over 18 months • 3 shots (0, 2, and 4 weeks ) may be effective for post-exposure treatment
Plague: Overview • Bacterial disease found in certain animals: • rats, squirrels, chipmunks, rabbits, and carnivores • Usual infection through contact with rodents/fleas that have bitten animals carrying plague • About 10-15 cases / year in U.S. • mainly SW states • bubonic most common form • only 1-2 cases / yr. of pneumonic form CDC: Wayson’s Stain of Y. pestis showing bipolar staining
Plague: Bubonic • Incubation: 2-6 days • Sudden onset headache, fatigue, muscle aches, fever, tender lymph nodes • Lymph nodes in area of flea bite will swell (Buboes) • Not contagious USAMRIID: Inguinal/femoral buboes
Plague: Pneumonic • Incubation: 1-3 days • Sudden onset headache, fatigue, fever, muscle aches, cough • Pneumonia progresses rapidly to shortness of breath, patient coughs up blood • Death from respiratory collapse and spread of infection to blood • Can be contagious USAMRIID: Pneumonic infiltrate of pneumonic plague
Plague: Prophylaxis • Bubonic contacts • Consider Doxycycline, Tetracycline, or sulfa drug for 7 days • other close contacts, fever watch for 7 days (treat if febrile) • Pneumonic contacts • consider Doxycycline, Tetracycline, orulfa drug for 7 days • Vaccine no longer manufactured in U.S. • not protective against pneumonic plague
Tularemia: Overview • Acquired through contact with blood/tissue of infected animals, or bites of infected deerflies, mosquitoes, or ticks • About 200 cases/year in U.S. • most in rural South central and Western states • majority of cases in summer (tick exposure) • No person-to-person transmission
Tularemia: Clinical Forms • Many different types of infections in lymph nodes, can also occur in eyes • Pneumonia • Possible presentation for bioterrorist attackBT
Tularemia: Pneumonic • Incubation: 3 to 5 days (range 1-21 days) • Abrupt onset fever, chills, headaches, muscle aches, non-productive cough • Patchy pneumonia on chest x-ray • Mortality 30% if untreated; < 10% if treated with antibiotics USAMRICD: Pneumonic infiltrates of pneumonic tularemia
Tularemia: Treatment/Prophylaxis • Treatment • Streptomycin or Gentamicin • Tetracyclines • Post Exposure Prophylaxis • Fever watch for 7 days (preferable) • Doxycycline or Tetracycline for 14 days if febrile (Cipro also possible) • Vaccine investigational • Not available for general use • Role in treatment of disease or post-exposure prophylaxis unknown