Transcript Diseases of Bioterrorist Potential For Environmental

Preparing for and Responding to
Bioterrorism:
Information for the Public Health
Workforce
Northwest Center for Public Health Practice
University of Washington School of Public Health and Community Medicine
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Acknowledgements
This presentation, and the accompanying instructor’s manual,
were prepared by Jennifer Brennan Braden, MD, MPH, at the
Northwest Center for Public Health Practice in Seattle, WA, for the
purpose of educating public health employees in the general aspects of
bioterrorism preparedness and response. Instructors are encouraged
to freely use all or portions of the material for its intended purpose.
The following people and organizations provided information and/or
support in the development of this curriculum. A complete list of
resources can be found in the accompanying instructor’s guide.
Patrick O’Carroll, MD, MPH
Project Coordinator
Centers for Disease Control and Prevention
Judith Yarrow
Design and Editing
Health Policy and Analysis; University of WA
Washington State Department of Health
UW Northwest Center for Public Health Practice
Jeff Duchin, MD
Jane Koehler, DVM, MPH
Communicable Disease Control,
Epidemiology and Immunization Section
Public Health - Seattle and King County
Ed Walker, MD; University of WA
Department of Psychiatry
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Diseases of Bioterrorist Potential
Environmental Sampling & Decontamination
CDC, AFIP
UW Northwest Center for Public Health Practice
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Learning Objectives

Describe:
 The
indications and purpose for collecting
environmental samples for biological testing
 The
indications and procedures for
decontamination following a spill or aerosol
release of a critical biological agent
UW Northwest Center for Public Health Practice
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Learning Objectives

List the agencies involved in environmental
sampling and decontamination

Identify the requirements for personal protective
equipment when collecting environmental
samples

Be able to locate sampling and packaging
protocols for critical biological agents
UW Northwest Center for Public Health Practice
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Environmental Sampling

May be useful for
 Determining the extent and degree of
contamination
 Supporting cleanup or medical decisions
 Guiding when cleanup adequate to permit
re-entry

The site of a deliberate release is a crime scene
 Preservation of evidence important
 Sampling conducted by law enforcement and
HAZMAT
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Environmental Sampling
Personal Protective Equipment

Powered air-purifying respirator with
full facepiece and HEPA filter

Disposable protective clothing




Garment with integral hood and booties
Disposable gloves
Remove and discard before removing respirator
Decontaminate all PPE immediately after
leaving a potentially contaminated area
UW Northwest Center for Public Health Practice
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Environmental Sampling
Pre-Sampling Considerations

Decision to collect
 Made by experts familiar with organism &
sampling methodologies
 Consult w/local, state, & federal agencies
 Nature & location of suspected contamination
 Medical diagnoses & opinions
 Potential for migration of contaminant
 Facility uses
UW Northwest Center for Public Health Practice
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Environmental Sampling
Pre-Sampling Considerations

Occupational & environmental exposure
standards

Currently none exist for B. anthracis spores

Validated sampling & analytical methods

Decontamination of sampling equipment, if not
disposable
UW Northwest Center for Public Health Practice
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Environmental Sampling
Pre-Sampling Considerations

Room airflow patterns
Discuss with building engineer
 May need to shut off ventilation
systems serving contaminated area


Size of contaminated area

Secure potentially contaminated areas to prevent
cross-contamination & re-aerosolization
Access control may be sufficient for small,
discrete, & lightly contaminated areas
Larger areas may need to be sealed off


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Environmental Sampling
Pre-Sampling Considerations

Sampling plan

Move inward toward suspected release source,
following anticipated contaminant pathway
 Sample
 Bulk,
types
surface, HEPA vacuum or air samples
 Number
of samples
 Sufficient
to represent extent of contamination
 Include field and media blanks
 Chain
of custody procedures
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Environmental Sampling
Rapid-Assay Devices

Intended only for screening of environmental
samples

Not currently recommended by CDC

Accuracy limited by technology

Negative result does not rule out lower level
of contamination

Positive results have been obtained with nonanthrax bacillus bacteria
UW Northwest Center for Public Health Practice
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Environmental Assessment Protocols

Contact the appropriate state health agency for
information on environmental assessment and
sampling protocols during an outbreak
In Washington:
 Food: Communicable Disease Epidemiology
(206) 361-2914
 Drinking Water: Division of Drinking Water
http://www.doh.wa.gov/ehp/dw/Staff_Lists/dwnames.htm

Environmental Health Assessments
(360) 236-3200
UW Northwest Center for Public Health Practice
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Packaging Critical Biological Agents
High-Probability Substances

Triple packaging
 Primary
receptacle
 Water-tight
 Durable


secondary packaging
outer packaging
“Infectious Substance” label
Performance tests as outlined by DOT, USPS,
PHS, IATA
Links to transportation &
transfer regulations
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UW Northwest Center for Public Health Practice
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Packaging Critical Biological Agents
Low-Probability Substances

Triple packaging

“Clinical Specimen” label

Performance requirement:
 No leakage after 4-ft drop test
UW Northwest Center for Public Health Practice
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Sample Analysis

Should occur at a member of the Laboratory
Response Network (LRN)
 Multilevel
network of local, state, and federal
laboratories
 Laboratories
identified by increasing level of
sophistication (A – D)

Level A: Rule-out testing

Levels B & C: Rule in, depending on agent
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Sample Analysis of Critical Biological Agents
Required Biosafety* Levels
B. anthracis
BSL-2
Y. pestis
BSL-2
C. botulinum
BSL-2
F. tularensis
BSL-2/3
Variola major
BSL-4
Filoviridae &
arenaviridae
BSL-4
UW Northwest Center for Public Health Practice
*BSL-2/3 - State and some local public health labs
BSL-4 - CDC & USAMRIID
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Laboratory Response Network
For Bioterrorism
Level D Lab
BSL-4
D - Highest level characterization (federal)
C - Molecular assays, reference capacity
Level C Lab
BSL-3
Level B Lab
BSL-2 facility + BSL-3 Safety
Practices
Level-A Lab
Use Class II Biosafety Cabinet
UW Northwest Center for Public Health Practice
B - Limited confirmation and transport
A - Rule-out and forward organisms
Source: CDC
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Environmental Decontamination
Buildings & Facilities


Standard procedures exist for Department of
Defense biological laboratories
 Labs built with decontamination requirements
in mind
 Experience limited
Public facilities present additional challenges
 Can be large, with many corners & crevices
 HVAC systems
 Electronic or other sensitive equipment
 Porous materials
 No standards of “cleanliness”
UW Northwest Center for Public Health Practice
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Bio Lab Decontamination
Standard Agents



Combination of vapor methods, surface
decontamination, sterilization, incineration
Space decontamination with vapor
 Paraformaldehyde
 Ethylene Oxide
 Beta-Propiolactone
 Vaporized hydrogen peroxide
Sterilization
 Steam (autoclaving)
 Dry heat
 Ultraviolet light
UW Northwest Center for Public Health Practice
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Bio Lab Decontamination
Standard Agents, cont.


Surface decontamination
 Chlorines
 Iodinein
 Ethyl or isopropyl alcohol
 Quarternary ammonium compounds
 Phenolic compounds
 Cresols (e.g., Lysol)
Incineration
UW Northwest Center for Public Health Practice
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Anthrax
Overview

Hardy spore found naturally in soil

Spores can survive for decades

Humans “naturally” infected by contact with
infected animals or contaminated animal
products

Can also be acquired by inhalation
(Woolsorter’s disease)

Anthrax not transmitted person-to-person
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Anthrax
Deposition of Particles in the Environment

Infectious aerosol particles >5 in size fall from
atmosphere and bond to surfaces


Secondary aerosolization unlikely
Particles 1-5 behave like a gas and are
deposited in small air sacs of the lungs

No environmental residue
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Anthrax
Decontamination

Environmental decontamination
 May decrease the small risk of secondary
aerosolization if area near spill or point of
aerosol release is heavily contaminated with
spores

Personal decontamination
 If direct contact with substance alleged to be
anthrax, wash exposed skin & clothing with
soap & water
UW Northwest Center for Public Health Practice
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2001 Anthrax Outbreak
Antimicrobial Pesticides for Decontamination

Sanitizers & disinfectants
 Sodium hypochlorite (bleach)
 Hydrogen peroxide and peroxyacetic acid

Sterilants/sporicides
 Chlorine dioxide gas
 Ethylene oxide
 Paraformaldehyde
UW Northwest Center for Public Health Practice
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Smallpox
Overview

Spread primarily by respiratory droplets > aerosols
> direct contact

Virus maintains infectivity for prolonged periods
out of host




Contaminated clothing and bedding can be infectious
Survives longer in cooler, drier climates
Virus found in scabs as long as 13 years later
Is transmitted person-to-person
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Smallpox
Decontamination

Performed by vaccinated personnel only

Protective clothing includes gowns, gloves,
shoe covers, caps, & masks

Bag & incinerate or autoclave protective clothing
and cleaning equipment after use

Immediately shower with soap & water after
contaminated protective clothing is removed

Disinfect vacuum cleaners with a phenolic
germicidal detergent
UW Northwest Center for Public Health Practice
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Smallpox
Decontamination

Contaminated horizontal surfaces




Wet with 5% aqueous solution of a phenolic
germicidal detergent
Allow to stand for at least 20 minutes
Wet vacuum or wipe with clean cloths
Facilities or rooms used to house patients




Surface decontamination, as above
Formaldehyde decontamination
Bag & incinerate or autoclave all disposable items
Autoclave or launder bedding, linens, & reusable
clothing in hot water and bleach
UW Northwest Center for Public Health Practice
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Plague
Overview

Caused by a non-spore-forming bacteria

Resistant to freezing temperature & drying,
killed by heat & sunlight

Human plague occurs from bite of an infected
flea (bubonic)

Pneumonic plague occurs after inhaling
aerosolized particles
 Spread
person-to-person
UW Northwest Center for Public Health Practice
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Plague
Decontamination

Environmental decontamination probably not
necessary
 Bacteria
does not survive long outside host
estimate – aerosol infectious for as
long as 1 hour
 WHO

Personal decontamination – soap & water

Hospital rooms, equipment, & bedding
 Decontamination
UW Northwest Center for Public Health Practice
per standard protocol
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Botulism
Overview



C. botulinum spores found in soil worldwide
Toxin causative agent of botulism
 Inactivated by chlorine (~20min) and
sunlight (1-3hrs)
 Destroyed by heat (5min at 85*C)
 Substantial decay estimated by 2 days
post-aerosol release
 Absorbed into circulation via mucosal
surface or wound, not intact skin
Not transmitted person-to-person
UW Northwest Center for Public Health Practice
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Botulism
Clinical Forms

Food-borne


Wound


Toxin produced by organisms contaminating wound
Infant


Toxin produced anaerobically in improperly
processed or canned, low-acid foods contaminated
by spores
Toxin produced by organisms in intestinal tract
Inhalation botulism

No natural* occurrence, developed as BW weapon
*3 accidental cases in veterinary personnel, W. Germany, 1962
UW Northwest Center for Public Health Practice
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C. Botulinum
Decontamination

Environmental decontamination
 Not
necessary if area can be avoided long
enough to allow natural degradation
 Otherwise,
clean contaminated surfaces with
0.1% hypochlorite solution


Wear mask & protective clothing
Personal decontamination – soap & water
UW Northwest Center for Public Health Practice
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Tularemia
Overview

Caused by non-spore forming bacteria

Survives for weeks in cold, moist environment

Sensitive to heat and disinfectants

Humans infected by various modes:





Handling contaminated animal tissues or fluids
Bite of infective deer flies, mosquitoes, or ticks
Direct contact with or ingestion of contaminated
water, food, or soil
Inhalation of infective aerosols
No person-to-person transmission
UW Northwest Center for Public Health Practice
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Tularemia
Decontamination

Heavily contaminated surfaces





Spray with 0.5% hypochlorite solution
After 10 minutes, 70% alcohol solution can be
used for further cleaning
Soap & water sufficient for less hazardous
contaminations
Personal decontamination – soap & water
Standard chlorination of water systems
sufficient to protect against water contamination
UW Northwest Center for Public Health Practice
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Viral Hemorrhagic Fevers



Diverse group of illnesses caused by RNA
viruses from 4 families
 Includes Ebola virus, Hantavirus, Yellow
Fever, among others
Potential for aerosol dissemination, with human
infection via respiratory route (except dengue)
Person-to-person transmission possible via
body fluids
UW Northwest Center for Public Health Practice
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Viral Hemorrhagic Fevers
Decontamination

Surface decontamination: 0.05% bleach solution

Other contaminated materials
 Autoclave,
incinerate or decontaminate with
0.05% bleach solution or phenolic
disinfectants
UW Northwest Center for Public Health Practice
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Summary of Key Points

Appropriate personal protective equipment for
workers conducting environmental sampling
includes a powered air purifying respirator with
full facepiece and HEPA filter, disposable
clothing, and gloves.

The decision to conduct environmental sampling
is based on the nature of the contamination and
the characteristics of the contaminated facility.
UW Northwest Center for Public Health Practice
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Summary of Key Points

Environmental sampling, packaging, and
transportation should follow appropriate state
protocols and federal regulations.

Samples should be analyzed for agents of
bioterrorist concern at a facility that is part of the
Laboratory Response Network for Bioterrorism
(LRN).
UW Northwest Center for Public Health Practice
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Summary of Key Points

Persons having direct contact with agents of
bioterrorist potential should wash with soap and
water.

Antibiotic prophylaxis may be necessary if the
biological agent exposure involved airborne
particles.

Only vaccinated personnel should perform
smallpox decontamination.
UW Northwest Center for Public Health Practice
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Summary of Key Points

The decision to sample or decontaminate a
facility is a multi-agency decision and should
include experts at the local, state, and federal
levels.

Environmental decontamination is probably not
necessary for agents with a short survival time
(e.g., plague, botulinum toxin), if the area can
be avoided to allow natural degradation.
UW Northwest Center for Public Health Practice
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Resources

Centers for Disease Control & Prevention
 Bioterrorism Web page: http://www.bt.cdc.gov/
 CDC Office of Health and Safety Information
System (personal protective equipment)
http://www.cdc.gov/od/ohs/

Environmental Protection Agency
http://www.epa.gov

USAMRIID
http://www.usamriid.army.mil/

Johns Hopkins Center for Civilian Biodefense
Studies http://www.hopkins-biodefense.org
UW Northwest Center for Public Health Practice
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