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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 1 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 2 Diseases of Bioterrorist Potential Environmental Sampling & Decontamination CDC, AFIP UW Northwest Center for Public Health Practice 3 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 4 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 5 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 UW Northwest Center for Public Health Practice 6 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 7 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 8 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 9 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 UW Northwest Center for Public Health Practice 10 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 UW Northwest Center for Public Health Practice 11 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 12 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 13 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 UW Northwest Center for Public Health Practice 14 UW Northwest Center for Public Health Practice 15 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 16 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 UW Northwest Center for Public Health Practice 17 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 18 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 19 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 20 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 21 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 22 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 23 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 24 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 25 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 26 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 27 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 28 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 29 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 30 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 31 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 32 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 33 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 34 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 35 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 36 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 37 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 38 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 39 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 40 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 41 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 42 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 43