Download Recognition and Management of Bioterrorism Agents

Biologic Disasters
Bruce Friedberg, MD
Department of Emergency Medicine, John Muir
Medical Center- Concord Campus
Disaster Preparedness Committee
Objectives
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Review of most likely agents
Clinical signs and symptoms
Management review
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Treatments
Infection control
Post-exposure prophylaxis
Vaccinations available
Four AM in the ED
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36 year old male presents with fevers and
chills, non-productive cough and nausea
Physical exam reveals a well developed male
in a Rolling Stones tee shirt
VSS except for a fever of 100.4°, physical
exam is otherwise normal
CBC shows mild elevation in WBC,
Electrolytes are normal
Patient is hydrated with one liter of NS and
discharged with a DX of “Viral Syndrome”
Four AM in the ED
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While getting ready to
discharge the patient, the
nurse finds he is now SOB,
with a fever of 104°
Upon returning from this CXR
he now has hemoptosis
Rapid progression into shock
and is declared dead at 7 am.
The nurse tells you that 25
new patients are in triage with
viral symptoms
Is this a Bioterrorism attack?
Epidemiology
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Clues suggesting a bioweapon release
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Large numbers present at once (epidemic)
Previously healthy persons affected
High morbidity and mortality
Unusual syndrome or pathogen for region or
season
 Recent terrorist claims or activity
 Unexplained epizootic of dead, sick animals
Bioterrorism: Defined
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The intentional or threatened use of bacteria,
viruses, fungi or toxins to create panic, death
or disease.
 Purpose
 Creating fear
 Illness
 Death
 Disruption of social and economic infrastructure
Our Role
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High level of suspicion
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Disease Surveillance
 Hoofbeats could be a zebra
 hospitals will likely be the 1st with the ability to
recognize an attack- We are the first line of defense
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Recognize typical BT disease syndromes
Know treatment/prophylaxis of BT agents
Know how to report suspected BT cases
Help protect your facility from contamination
 Will often require a decontamination washing.
 “Code Orange” used for multiple patients.
Why Bioterrorism Agents?
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Inexpensive $
 $2000
typical conventional weapon
 $1
biologic agent (50% casualties/km2)
Many casualties with minimal planning
Invisible, mimic several common illnesses
Long incubation periods allow escape time for
perpetrators
Easily procured
CDC Threat Classification
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Class A agents: most severe potential for
widespread illness and death
 Easily disseminated or transmitted from person to
person
 High mortality rates
 Easily weaponized
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Class B agents: less potential
Class C agents: future threats
Terrorist Dissemination Methods
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Aerosol likely route for
most agents
 Easiest to disperse
 Highest number of
people exposed
 Most contagious route of
infection
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Food / Waterborne less
likely
 Only effective for some
agents
Category A Diseases
 Anthrax (Bacillus anthracis)
 Smallpox (variola virus)
 Plague (Yersinia pestis)
 Tularemia (Francisella tularensis)
 Botulism (botulinum toxin)
 Viral Hemorrhagic Fever
Anthrax
Bacillus anthracis
Anthrax
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2001 (fall)- anthrax mailings
 NBC news, Sen. Tom Daschle
 22 total cases/ 11 inhalation/ 5 deaths
Anthrax: info
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Cutaneous
Gastrointestinal (rare)
Inhalation
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Spores are Odorless/Invisible
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Likely dissemination route:
Aerosolization
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Cutaneous anthrax
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2000 cases annually (worldwide)
Transmitted from Herbivores
Skin is exposed to spores
Painless, pruritic papule develops
“Painless” black eschar follows
1-14 day latent period
Mortality: 20%, if untreated
Readily responds to Ciprofloxacin
Inhalation anthrax: clinical
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18 cases in US between 1900-1976
Follows inhalation of spores
Possible sixty day delay in symptoms
Estimated 3 million deaths from 100 kg release
(spores can travel airborne for 60 miles)
During fall 2001 “mailings”
 45% mortality
 4 day latent period
Inhalation anthrax: clinical
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Initial sxs (hours to days):
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Malaise, drenching sweats
Low-grade fever
Non-productive cough
Nausea/ vomiting
Terminal sxs (usually hours)
 abrupt dyspnea, stridor, cyanosis
 Rapid progression to shock and death
Inhalational anthrax: clinical
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CXR (10/11 in 2001 mailings
were abnormal):
 Hemorrhagic mediastinitis
with widened mediastinum
on CXR
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Peripheral Blood smear
shows Gram-positive bacilli
Aerobic Blood culture shows
growth of large, grampositive bacilli
Anthrax: treatment
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Infection Control
 Standard precautions
 If cutaneous wear gloves
 Not transmitted from person to person
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Give Antibiotics Early
 Ciprofloxacin
 Doxycycline
Anthrax: treatment
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All post-exposure contacts should be treated
for 60 days
 Ciprofloxacin
 Alternate: doxycycline
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Vaccine (developed in 1970s)
 Used by military
Smallpox
Orthopoxvirus (variola species)
Smallpox: info
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One of highest-threat bioterrorism agents
 High case fatality rate
 Lack of specific therapy
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Routine US vaccines stopped in 1972
 Herd immunity no longer present
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Likely dissemination route: Aerosolization or
human carriers
Small pox: info
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12- 14 day incubation period
Most infective during initial rash period
Less infective after crusting of lesions
Smallpox
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vs
12-14 day incubation
Prodromal symptoms
Slow development of rash
Centrifugal: greatest
concentration of lesions
on face and extremities
Synchronous lesions
Varicella
 14-21 day incubation
 Minimal prodromal
 Rapid development of rash
 Centripetal: seldom on
soles and plams
 Asynchronous lesionssuccessive crops
Smallpox
vs
Varicella
Smallpox: treatment
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Supportive only
Infection control
 Pt isolation
 Standard, Contact & Airborne precautions (N-95
mask recommended)
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Immunized individuals should be protected
Antiviral agents not currently recommended
Smallpox: Prophylaxis
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Vaccine within 4 days of exposure can lessen
severity of infection
 Contraindicated in immunocompromised and pts
with eczema
 “there is enough smallpox vaccine to vaccinate
every person in the United States in the event of a
smallpox emergency”
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Vaccinia immune globulin (VIG)
 Within 2-3 days of exposure
 Consider for those with contraindications to the
vaccine
Botulinum Toxin
Clostridium botulinum
Botulism toxin: info
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Most poisonous substance known
Occurs naturally in soil (odorless, colorless,
tasteless)
Most cases from contaminated undercooked meat
(inactivated if >85 C for 5 minutes)
Toxin has neuroparalytic effects
Toxin irreversibly binds to acetylcholine receptors
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Likely dissemination route:
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 Contamination of food or Aerosolization
Botulism: info
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Mortality:
 Treated = < 5%
 Untreated = up to 60%
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Diagnosis is CLINICAL
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Incubation of 2 hours to 8 days
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Many casualties will require long term respiratory
support
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Confirmatory testing is slow (only at CDC and 20
other public health sites)
Botulism: clinical
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Afebrile
Descending flaccid paralysis
Bulbar deficits initially
Four “D’s”
 Diplopia
 Dysarthria
 Dilated pupils
 Dysphagia
Botulism: treatment
Supportive care
Respiratory support could be for months
new motor axons must grow to paralyzed areas
Antitoxin (available only from CDC)
May prevent spread of paralysis, BUT does not
reverse paralysis
Infection Control
Standard precautions
Botulism: prevention
 No effective post exposure prophylaxis
 +/- Antitoxin
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Vaccine
 DOD pentavalent toxoid is available
 Used for last 30 years in lab workers
Plague
Yersinia pestis
Plague: info
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The “Black Death” has caused more fear
and terror than perhaps any other
infectious disease in history
 It has laid claim to at least 200 million lives
 Most human cases are from bites from infected
fleas who have had a blood feed from an
infected rodent
 Human to human transmission occurs only in
pneumonic plague from direct inhalation
 Likely dissemination route: Aerosolization
Plague
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Bubonic
Septicemic
Pneumonic
Plague: clinical
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Usually present 2-8 days after exposure
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Sudden onset of fever, chills, weakness +/-acutely
swollen painful lymph nodes
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Swollen lymph nodes = “Buboes”
 possibly suppurative
Bubonic and septicemic plague:
clinical
Symptoms +
Buboes present
Bubonic plague
Symptoms without
Buboes
Septicemic plague
-gram-negative sepsis
-DIC
Pneumonic Plague: clinical
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Approaches 100% fatality rate (untreated)
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Highly contagious
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Within 24 hours of exposure:
 High fever
 Vomiting and abdominal pain
 Cough with bloody sputum
 DIC
Pneumonic Plague: clinical
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DX with sputum secretions/ Gram stain & culture
Plague: treatment
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Infection Control
 Standard and droplet precautions (if pneumonic
plague suspected)
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Antibiotics recommended (for 10 days)
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Start treatment prior to ID (delay can decrease
survival)
 Streptomycin (reduces mortality to 5-14%)
 Gentamicin, Ciprofloxacin,Doxycycline,
Chloramphenicol
Plague: prevention
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Post exposure prophylaxis:
 Treat with antibiotics for seven days
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No vaccine is currently available (previously
used in military)
Tularemia
Francisella tularensis
Tularemia: info
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Infection occurs naturally from bites by infected
arthropods, handling infectious animal tissues,
contact with or ingestion of contaminated food,
water, or soil and inhalation of infective
aerosols
No person to person transmission
Survives for weeks in water, moist soil, straw,
and decaying animal carcasses
The signs and symptoms people develop
depend on how they are exposed to tularemia
Tularemia- clinical forms
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Ulceroglandular
Pleuropneumonitis
Oropharyngeal
Oculoglandular
Septicemic
Tularemia: clinical
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1-14 day incubation
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If inhaled, symptoms can include abrupt onset
of fever, chills, headache, muscle aches, joint
pain, dry cough, and progressive weakness
One of the most infectious pathogenic bacteria
known.
Inhalation of as few as 10 organisms can
cause disease.
Likely dissemination route: Aerosolization
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Tularemia- treatment
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Infection Control
 Contact and Airborne Precautions
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Use Antibiotics (14-21 days)
 Streptomycin
 Gentamicin
 Ciprofloxacin
Tularemia- prevention
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Post-exposure prophylaxis
 Doxycycline
 Ciprofloxacin
 Tetracycline
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Vaccine available
 Live attenuated vaccine (under FDA review)
Viral Hemorrhagic Fevers (VHF)
Ebola, Lassa, Yellow Fever, Dengue , Marburg,
etc
,
VHF: info
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RNA viruses
Since 1967, 18 outbreaks with 1500 patients
Most cases from direct contact with blood or
secretions
Vectors
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Likely dissemination route: Aerosolization
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 Rodents
 Mosquitoes
 Ticks
VHF: signs and symptoms
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Incubation of 2-21 days
Target Organ=Vascular
bed
Micro vascular damage
Vascular permeability and
bleeding
VHF: signs and symptoms
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EARLY:
 Fever/ Myalgia/ Malaise/ Headache
 N/V/D
 Maculopapular rash on trunk
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LATE:
 bleeding under the skin, internal organs or from
body orifices like the mouth, eyes and ears
 Multi-organ dysfunction
VHF: treatment
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Supportive care
Infection Control
 Contact and Airborne precautions
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Isolation of patients
Ribavirin (recommended by
CDC for suspected cases)
VHF: prevention
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No post-exposure prophylaxis
No licensed vaccines currently available
CDC Threat Classification –
Category B
Agents
Coxiella burnetti
Brucella species
Burkholderia mallei
Ricinus communis
(castor beans)
Clost. perfringens
Staphylococcus
Disease
Q fever
Brucellosis
Glanders
Ricin Toxin
Epsilon toxin
Enterotoxin B
CDC Classification – Category C
Agents
Nipah virus
Hantaviruses
Tickborne
hemorrhagic fever
Role of Primary Care Physician
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Have a high level of suspicion
 Keep BT agents in differential diagnosis
Use Standard Precautions at all times
Maintain high suspicion with “clusters” of similar
cases or presenting symptoms
Who you gonna call?
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Contra Costa Health Services Public Health
Division IMMEDIATELY:
 925-313-6740 or after hours/weekends/holidays:
925-646-2441 (ask for the on-call Health Officer)
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They will arrange for
 specialized lab testing
 provide situational assessment and infection
control guidelines
 Activate state and federal response plans
Strategic National Stockpile (SNS)
Program
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CDC has a large
stockpile of
medicine and
medical supplies
To be used in a
public health
emergency severe
enough to cause
local supplies to run
out
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12-Hour Push
Package
Questions???