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Public Health CBRN course CBRN overview Daniel Kollek, MD, CCFP(EM)
Goals of session • To provide an overview of the categories and actions of CBRN agents and the roles of Public Health in responding to them
Outline of session • • • Definitions Chemical overview Biological overview Radiological overview Nuclear overview Roles of public health
Definitions Chemical Biological Radiological Nuclear Public Health role
(1) Definitions Disaster • The Merriam-Webster dictionary • definition of disaster is "a sudden or great misfortune. " The Medical definition if a disaster is "when the destructive effects of an event overwhelm the ability of a given area or community to meet the demand for health care. "
(1) Definitions Mass Casualty Incident A disaster that is typified by a large number of patients that outstrip resources on the basis of numbers of individuals requiring care.
(1) Definitions CBRN Disasters contaminated by an agent that can be Chemical Biological Radioactive or Nuclear. Each one of these has specific response needs. Also known as NBC or ABC
(1) Definitions Terrorism A terror attack is defined as an attack targeted at civilian non-combatants for the purpose of affecting the government that represents them. A successful terror event involves large number of casualties, may involve CBRN contaminants, causes infrastructure damage and has a psychological impact
Definitions Chemical Biological Radiological Nuclear Public Health role
(2) Chemical Agents • What is a hazardous material? • How do we classify chemical agents? • What are the chemical agents we worry • about (and why)? What type of incidents might we face?
(2) Chemical Hazardous Material A substance is considered hazardous when, because of its quantity, concentration, or physical characteristics, it poses a real hazard to human health or the environment Mississauga train derailment 1979
(2) Chemical Agent Classification Nerve agent – organophosphate based, insecticides Blister agent – Vesicants Pulmonary agent – Choking (ie Phosgene, Chlorine) Blood agent - Cyanide Other agents Pepper spray, Tear gas, CS, OC
(2) Chemical “TICs and TIMs” Toxic Industrial Chemicals • Irritants (chlorine, phosgene, hydrogen chloride, ammonia, isocyanates) • Pharmacologic-like agents (cyanide) • Hydrocarbons • Alcohol-based solvents • Corrosives (acids & bases) • Pesticides (organophosphates and others) • Smoke • Riot Control (Tear Gas & Pepper Spray)
(2) Chemical Incident Types • Small, localized Haz. Mat Incident – 84% of incidents occur at fixed sites – 70% involve 1 or 2 victims – 90% are ambulatory – Liquid contamination more common – Greater need for showering • Chemical MCI – Most commonly gas or vapor exposure – Most exposures are mild with few significant toxic effects – Beware of incidents in enclosed spaces – Clothing removal is the focus of decontamination
(2) Chemical Response to chemical agents • Decontamination • Antidotal therapy – 2 PAM, – Atropine, – Benzodiazepines
(3) Biological Definitions Chemical Biological Radiological Nuclear Public Health role
(3) Biological Types of Bio-agents • Bacterial • Viral • Toxins
(3) Biological Characteristics of Bio-agents • • Low visibility High potency Latency Easy accessibility Simple delivery Good sustainability and propagation Does Not Affect Structures
(3) Biological Entry Modes • • Inhalation Ingestion Injection Absorption
(3) Biological Bioterrorism agents Category A Diseases/Agents Organisms that pose a risk to national security because they: • can be easily disseminated or transmitted from person to • • • person; result in high mortality rates and have the potential for major public health impact; might cause public panic and social disruption; and require special action for public health preparedness.
(3) Biological A level bioterrorism agents • • • Anthrax (Bacillus anthracis) Botulism (Clostridium botulinum toxin) Plague (Yersinia pestis) Smallpox (variola major) Tularemia (Francisella tularensis) Viral hemorrhagic fevers (filoviruses [e. g. , Ebola, Marburg] and arenaviruses [e. g. , Lassa, Machupo])
(3) Biological Bioterrorism agents Category B Diseases/Agents Second highest priority agents include those that: • are moderately easy to disseminate; • result in moderate morbidity rates and low • mortality rates; and require specific enhancements of laboratory diagnostic capacity and enhanced disease surveillance.
(3) Biological B level bioterrorism agents • Brucellosis (Brucella species) • Epsilon toxin of Clostridium perfringens • Food safety threats (e. g. , Salmonella species, Escherichia • • • coli O 157: H 7, Shigella) Glanders (Burkholderia mallei) Melioidosis (Burkholderia pseudomallei) Psittacosis (Chlamydia psittaci) Q fever (Coxiella burnetii) Ricin toxin from Ricinus communis (castor beans) Staphylococcal enterotoxin B Typhus fever (Rickettsia prowazekii) Viral encephalitis (alphaviruses [e. g. , Venezuelan equine encephalitis, eastern equine encephalitis, western equine encephalitis]) Water safety threats (e. g. , Vibrio cholerae, Cryptosporidium parvum)
(3) Biological Bioterrorism agents Category C Diseases/Agents Third highest priority agents include emerging pathogens that could be engineered for mass dissemination in the future because of: • availability; • ease of production and dissemination; and • potential for high morbidity and mortality rates and major health impact.
(3) Biological C level bioterrorism agents • Emerging infectious diseases such as Nipah virus and hantavirus
(4) Radiological Definitions Chemical Biological Radiological Nuclear Public Health role
(4) Radiological What Is Radiation? Radio/TV Sun Nuclear Heat Light Microwave
(4) Radiological Electromagnetic Spectrum Increasing Energy and Frequency Radio/TV Microwave Electrical Power X-ray Light NON-IONIZING RADIATION UV Increasing Harm Gamma IONIZING RADIATION
Health Effects of Radiation Exposure (4) Radiological • Lethal at high doses • Mutagenic • Carcinogenic • Other biological effects, especially at high doses
(4) Radiological Decrease Radiation Effects Time: Decrease time spent near the radioactive source Distance: Increase distance between you and the source Shielding: Increase the physical shielding between you and the source
(4) Radiological Common Shelters Structure Wood Frame (1 st floor) Wood Frame (Basement) Masonry Large building Dose Reduction Factors 10% 40% 80% From the Environmental Protection Agency’s Manual of Protective Action Guides and Protective Actions for Nuclear Incidents, Appendix C
(4) Radiological Potential Terrorist Scenarios • Radiological – Radiological dispersion device; e. g. , “dirty bomb” – Malicious use of radioactive substances • Nuclear – Attack on nuclear facility – Nuclear weapon – Improvised nuclear device (IND)
(4) Radiological Mass Radiological Casualties “For an improvised nuclear device >100, 000 patients could require evaluation and treatment. ” Department of Homeland Security Working Group on Radiological Dispersal Device (RDD) Preparedness, Medical Preparedness and Response Sub-Group Report (May, 2003)
(4) Radiological Radioactive Sources • 157, 000 licensed users in U. S. • 2, 000 devices containing radioactive sources • Approximately 400 sources lost or stolen in U. S. every year
(4) Radiological Sources Around the World Recovered transport container Sources used in mobile cesium irradiators in the former Soviet Union Photos courtesy of the International Atomic Energy Agency (IAEA)
(4) Radiological Goiânia Radiological Release Obsolete radiotherapy machine Abandoned cancer clinic Photos courtesy of the International Atomic Energy Agency (IAEA)
(4) Radiological Goiânia Morbidity • 249 exposed; 54 hospitalized • Eight with radiation sickness • Four people died • 112, 000 people monitored (>10% of total population) Photos courtesy of the International Atomic Energy Agency (IAEA)
(4) Radiological How do you categorize exposures?
(4) Radiological Categorization • External contamination – Patient is radioactive! – Remove all clothes is most important part of decontamination • Irradiation - local or whole body – Patient is not radioactive and poses no risk to others! • Ingestion – Body fluids may be radioactive • Combination of above
(4) Radiological Remember! Categorisation determines risk to others and can identify specific therapeutic steps to be taken Dose determines severity, treatment plan and prognosis
(5) Nuclear Definitions Chemical Biological Radiological Nuclear Public Health role
(5) Nuclear Key Issues in Nuclear Event • Same concerns as radiation event • Added concerns of mass trauma and major system disruption
So what have we learned so far?
CBRN comparison Biologic Onset Slow Nuclear/ Radn Rapid Chemical Rapid Transmission/ Slow, Agent infectivity dependant Particulate only, Fast, Agent Fast dependant Detection Difficult Easier Resource consumption Gradual, long term Rapid, short and Rapid, short long term Some long term Public Health involvement Short & long term Short term Bed use Mixed Hospital Decon. requirements Agent dependant Critical for particulate Critical for all Antidote Agent dependant None Class dependant Easier
(5) Public Health Definitions Chemical Biological Radiological Nuclear Public Health role
(5) Public Health Role • • • Early Detection Mass Patient Care Mass Immunization/Prophylaxis Epidemiologic investigation Communication Command Control
(5) Public Health Role (2) • Mass Fatality Management • Evacuations/sheltering (humans and animals) • Environmental Surety • Community Recovery (rapid health risk assessment, mental health etc)
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