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UCLA Center for Public Health and Disasters Bioterrorism Training for Physicians Updated March 2003 Over 1700 Downloads Since Going Online October 2001 Available at: http://www.ph.ucla.edu/cphdr/bioterrorism. BIOTERRORISM:. Are You Prepared?. Bioterrorism 101. Why is this a problem?
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UCLA Center for Public Health and DisastersBioterrorism Training for PhysiciansUpdated March 2003Over 1700 Downloads Since Going Online October 2001Available at: http://www.ph.ucla.edu/cphdr/bioterrorism
BIOTERRORISM: Are You Prepared?
Bioterrorism 101 Why is this a problem? Who and what are the agencies worrying about?
Biological Terrorism Intentional or threatened use of viruses, bacteria, fungi or toxins from living organisms to produce death or disease in humans, animals or plants
Biological Terrorism – Why? • Small amounts – devastating effects • Invisible, odorless, tasteless • Easy to obtain • Difficult to detect • Civilian populations unprotected • Delayed onset - difficult to trace • Publicity, fear, chaos
What Happens in a Bioterrorism Incident? That depends on whether the attack is: OVERT or COVERT
Overt Attack • Threat Validation • Coordinated System Response • Traditional First Responders: Fire, Police, EMS • Hospitals • Community Practitioners • Public Health - Information Management • Law Enforcement
Overt Attack • Problems: • Verifying if an attack has taken place • Fear, chaos • Large numbers of “worried well” • Decontamination • Limited supply of treatment, prophylactic drugs, and vaccines
Real or Hoax? • Public health and law enforcement will determine credibility, and need for decontamination or prophylaxis • Test results may take 24-48 hours
Covert Attack • EMS system may be used by cases (not yet recognized as a bioterrorist event) • Likely detected through hospitals, medical care practitioners • Clinical labs contact local PH department • PH department refers to State or CDC
Covert Attack • Problems with recognition: • Symptoms overlap common illnesses • Delayed onset of symptoms • Victims present to different centers • Secondary spread may occur before attack is recognized
Likely Scenarios • Aerosol release • Major city, large event, or key function • Victims presenting to different centers • Recognition of attack through symptoms, epidemiologic patterns or microbio lab
Aerosol Delivery • Considered the most likely route for BT • Aim is to generate invisible clouds of particles 0.5-10 microns in diameter • Can stay suspended for long periods of time • Perfect size to reach the alveoli in lungs • Aerosols of most agents produce systemic disease
Key Indicators of a BT Event • Sudden increase in severity or incidence of illness • Appearance of unusual (non-endemic) illness or syndrome in your community • Geographic and/or temporal pattern of illness • Occurrence of vector-borne disease where there is no vector
Key Indicators of a BT Event • Cluster of sick or dead animals • Atypical seasonality • Unusual expression of endemic disease • Multi drug-resistant pathogens
Category A: Top Priority Easily disseminated or transmitted High mortality Causes social disruption Special preparation needed Category A Agents: Anthrax Botulism Plague Smallpox Tularemia Viral Hemorrhagic Fevers Bioterrorism: The Agents
Category B Q Fever Brucellosis Viral encephalitides Staphylococcal enterotoxin B Food/Waterborne Ricin Category C Nipah virus Hantavirus Tickborne hemorrhagic fever Yellow fever Multidrug-resistant TB Bioterrorism: The Agents
Overview of the Agents:Clinical Manifestations and Treatment
Pneumonic Syndromes: Inhalational Anthrax Pneumonic Plague Pneumonic/Typhoidal Tularemia
Anthrax • Source: Bacillus anthracis • Bacterial spores and toxins • Cutaneous, inhalational and intestinal
Cutaneous Anthrax • Incubation 1-12 days • Papule > vesicle or ulcer > black centerover several days • Diagnosis: Gram stain and culture of unroofed vesicle, base of ulcer, under edge of eschar • Usually responds well to treatment
Inhalational Anthrax • Incubation: 1 - 6 days (rarely up to > 60 days) • Prodrome: 1-2 d fever, malaise, dry cough • Severe respiratory distress, septic shock, may have meningitis • Diagnosis • Hemorrhagic mediastinitis – wide on CXR • Isolation • Standard; not contagious
Anthrax vs. Viral Illness Anthrax Flu Other Viral Elev. Temp 70% 68-77 % 40-73% Cough 90 84-93 72-80 SOB 80 6 6 Pleuritic Pain 60 35 23 Headache 50 84-91 74-89 Sore Throat 20 64-84 64-84 Rhinorrhea 10 79 68 Nausea / Vom. 80 12 12 MMWR Nov 9 2001;50:984
Evaluation of Possible Inhalation Anthrax • History of exposure or risk + Symptoms: • WBC (bandemia), Blood culture – highest yield • CXR – wide mediastinum, effusion, or infiltrate Consider CT if CXR normal • If results abnormal or pt. seriously ill: Multi-drug treatment • If results normal and pt mildly ill: Observe and initiate single-drug prophylaxis
Anthrax - Treatment • Combination Rx for seriously ill: Cipro or Doxy + other drug(s) • Other drugs with activity include: Rifampin, Vancomycin, Clindamycin, Imipenem, Clarithromycin, PCN • Post-Exposure Prophylaxis: Cipro or Doxy X 60 d (X 30 d if given with vaccine)
Anthrax Exposure? • Most patients need only reassurance • Higher risk: • Threatening message • Sandy brown color powder • Suspicious letter or package • High-profile person or postal worker • If exposure is credible, contact police • Nasal swab NOT sensitive enough to r/o exposure for an individual
Plague Source • Bacterium: Yersinia pestis Forms • Bubonic, septicemic, and pneumonic** ** Suspect Bioterrorism
Pneumonic Plague • Incubation: 2-3 d • Symptoms • Fulminant pneumonia, bloody sputum, septic shock, high fever, chills, headache, possible disseminated intravascular coagulation • Diagnosis • Laboratory: Gram stain blood, sputum, node • Small, Gram-neg, bipolar (‘safety-pin’), poorly staining coccobacilli
Pneumonic Plague • Isolation • Highly contagious • Strict respiratory isolation until Rx for 3d • Followed by standard respiratory droplet precautions (masks, gown, gloves, eye protection) • Treatment • Streptomycin, doxycycline, or chloramphenicol • High mortality, but may respond to early treatment
Tularemia Source • Bacterium: Francisella tularensis • Gram neg. coccobacillus • Zoonotic (‘rabbit fever’) Forms • Ulceroglandular and typhoidal/pneumonic** **Suspect Bioterrorism
Tularemia • Incubation: 2-10 days • Prodrome: • Fever, headache, chills, myalgia, cough, nausea, vomiting, diarrhea • May present as pneumonia • Diagnosis • Laboratory: Culture/Gram stain blood, sputum, node • Culture can be difficult and is risky to lab personnel
Tularemia • Isolation • Standard; not contagious • No human-human transmission • Treatment • Streptomycin, gentamicin, or doxycycline • If exposed: watch for 7 days, treat if fever develops • Vaccine under review by FDA • Mortality 30% untreated; < 10% treated
Paralytic Syndrome: Botulism
Botulism Source: Clostridium botulinum neurotoxin • Types A, B, E, and F • Most potent toxin known • Lethal dose 1 ng/kg • 100,000 times more toxic than sarin
Botulism • Incubation: 1-5 days • Symptoms • Blocks cholinergic synapses • Dry mouth, blurred/diplopia, muscle weakness, dysphagia • Descending flaccid paralysis can last for weeks to months • Diagnosis • Clinical • A few labs can do serum toxin assay • Death from respiratory failure
Botulism • Isolation • Standard; not contagious • No human-human transmission • Decontaminate clothing, skin with soap and water • Treatment • Ventilatory support • Botulinum antitoxin - equine • Skin test for horse serum sensitivity • More effective if given early – will not reverse paralysis that has already occurred
Rash and Fever Syndromes: Smallpox Viral Hemorrhagic Fevers
Incubation: ~ 12 days (up to 17 days) Early symptoms nonspecific Fever, malaise, aches for 2-4 days; then severe illness Rash then appears on extremities with uniform appearance Scabs over in 1-2 weeks Contagious until ALL scabs have fallen off Smallpox: Presentation
Smallpox • Notify Public Health IMMEDIATELY • Diagnosis • Laboratory • Rule out chickenpox – PCR • Isolation • Strict contact and respiratory isolation (negative pressure) • Trace contacts up to 17 days prior to illness • Treatment • None known effective • Questionable effectiveness of Cidofovir • Mortality ~ 30%
Smallpox vs. Chickenpox VariolaVaricella • Incubation 7-17 d 14-21 d • Prodrome 2- 4 d minimal/none • Distribution extremities trunk • Progression similar growth dissimilar growth • Scab formation 10-14 d p rash 4-7 d p rash • Scab separation 14-28 d p rash <14 d p rash
Rash: extremities, uniform size Smallpox vs Chickenpox Rash: trunk, different stages of development
Smallpox Vaccine • Live Vaccinia virus • Given intradermal on bifurcated needle • Pustule – scab in ~ 1 week, mild fever • Can potentially spread to others until scab is gone • Lifelong immunity is questionable • Vaccinated persons probable reduced risk of mortality • Vaccine is effective up to several days AFTER exposure