Recognition and Management of Bioterrorism Agents
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Transcript 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
Review of most likely agents
Clinical signs and symptoms
Management review
Treatments
Infection control
Post-exposure prophylaxis
Vaccinations available
Four AM in the ED
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
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
Clues suggesting a bioweapon release
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
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
High level of suspicion
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
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?
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
Class A agents: most severe potential for
widespread illness and death
Easily disseminated or transmitted from person to
person
High mortality rates
Easily weaponized
Class B agents: less potential
Class C agents: future threats
Terrorist Dissemination Methods
Aerosol likely route for
most agents
Easiest to disperse
Highest number of
people exposed
Most contagious route of
infection
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
2001 (fall)- anthrax mailings
NBC news, Sen. Tom Daschle
22 total cases/ 11 inhalation/ 5 deaths
Anthrax: info
Cutaneous
Gastrointestinal (rare)
Inhalation
Spores are Odorless/Invisible
Likely dissemination route:
Aerosolization
Cutaneous anthrax
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
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
Initial sxs (hours to days):
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
CXR (10/11 in 2001 mailings
were abnormal):
Hemorrhagic mediastinitis
with widened mediastinum
on CXR
Peripheral Blood smear
shows Gram-positive bacilli
Aerobic Blood culture shows
growth of large, grampositive bacilli
Anthrax: treatment
Infection Control
Standard precautions
If cutaneous wear gloves
Not transmitted from person to person
Give Antibiotics Early
Ciprofloxacin
Doxycycline
Anthrax: treatment
All post-exposure contacts should be treated
for 60 days
Ciprofloxacin
Alternate: doxycycline
Vaccine (developed in 1970s)
Used by military
Smallpox
Orthopoxvirus (variola species)
Smallpox: info
One of highest-threat bioterrorism agents
High case fatality rate
Lack of specific therapy
Routine US vaccines stopped in 1972
Herd immunity no longer present
Likely dissemination route: Aerosolization or
human carriers
Small pox: info
12- 14 day incubation period
Most infective during initial rash period
Less infective after crusting of lesions
Smallpox
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
Supportive only
Infection control
Pt isolation
Standard, Contact & Airborne precautions (N-95
mask recommended)
Immunized individuals should be protected
Antiviral agents not currently recommended
Smallpox: Prophylaxis
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”
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
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
Likely dissemination route:
Contamination of food or Aerosolization
Botulism: info
Mortality:
Treated = < 5%
Untreated = up to 60%
Diagnosis is CLINICAL
Incubation of 2 hours to 8 days
Many casualties will require long term respiratory
support
Confirmatory testing is slow (only at CDC and 20
other public health sites)
Botulism: clinical
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
Vaccine
DOD pentavalent toxoid is available
Used for last 30 years in lab workers
Plague
Yersinia pestis
Plague: info
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
Bubonic
Septicemic
Pneumonic
Plague: clinical
Usually present 2-8 days after exposure
Sudden onset of fever, chills, weakness +/-acutely
swollen painful lymph nodes
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
Approaches 100% fatality rate (untreated)
Highly contagious
Within 24 hours of exposure:
High fever
Vomiting and abdominal pain
Cough with bloody sputum
DIC
Pneumonic Plague: clinical
DX with sputum secretions/ Gram stain & culture
Plague: treatment
Infection Control
Standard and droplet precautions (if pneumonic
plague suspected)
Antibiotics recommended (for 10 days)
Start treatment prior to ID (delay can decrease
survival)
Streptomycin (reduces mortality to 5-14%)
Gentamicin, Ciprofloxacin,Doxycycline,
Chloramphenicol
Plague: prevention
Post exposure prophylaxis:
Treat with antibiotics for seven days
No vaccine is currently available (previously
used in military)
Tularemia
Francisella tularensis
Tularemia: info
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
Ulceroglandular
Pleuropneumonitis
Oropharyngeal
Oculoglandular
Septicemic
Tularemia: clinical
1-14 day incubation
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
Tularemia- treatment
Infection Control
Contact and Airborne Precautions
Use Antibiotics (14-21 days)
Streptomycin
Gentamicin
Ciprofloxacin
Tularemia- prevention
Post-exposure prophylaxis
Doxycycline
Ciprofloxacin
Tetracycline
Vaccine available
Live attenuated vaccine (under FDA review)
Viral Hemorrhagic Fevers (VHF)
Ebola, Lassa, Yellow Fever, Dengue , Marburg,
etc
,
VHF: info
RNA viruses
Since 1967, 18 outbreaks with 1500 patients
Most cases from direct contact with blood or
secretions
Vectors
Likely dissemination route: Aerosolization
Rodents
Mosquitoes
Ticks
VHF: signs and symptoms
Incubation of 2-21 days
Target Organ=Vascular
bed
Micro vascular damage
Vascular permeability and
bleeding
VHF: signs and symptoms
EARLY:
Fever/ Myalgia/ Malaise/ Headache
N/V/D
Maculopapular rash on trunk
LATE:
bleeding under the skin, internal organs or from
body orifices like the mouth, eyes and ears
Multi-organ dysfunction
VHF: treatment
Supportive care
Infection Control
Contact and Airborne precautions
Isolation of patients
Ribavirin (recommended by
CDC for suspected cases)
VHF: prevention
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
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?
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)
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
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
12-Hour Push
Package
Questions???