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Bioterrorism Preparedness. Bonnie Henry, MD, FRCPC. Public health CBRN course. Goals of session. To provide a review of bioterrorism agents and history of BT use (with a focus on anthrax and smallpox) To review potential roles for public health in a BT incident
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Bioterrorism Preparedness Bonnie Henry, MD, FRCPC Public health CBRN course
Goals of session • To provide a review of bioterrorism agents and history of BT use (with a focus on anthrax and smallpox) • To review potential roles for public health in a BT incident • To review principles of laboratory testing of ‘suspicious packages’ and continuity of evidence
Bioterrorism is the intentional use of microorganisms (bacteria, viruses, and fungi) or toxins to produce death or disease in humans, animals or plants. Electron micrograph of anthrax bacteria Electron micrograph of ebola virus
Category A • “Biologic Threat Agents” • Can be easily disseminated or transmitted person-to-person; • Cause high mortality, w/potential for major public health impact; • Might cause public panic and social disruption; and • Require special action for public health preparedness.
Biological Agents of Highest Concern Category A • Smallpox – variola major • Anthrax – Bacillus anthracis • Plague – Yersinia pestis • Botulism – Clostridium botulinum toxin • Tularemia – Francisella tularensis • Viral hemorrhagic fevers – arenaviruses, filoviruses (Ebola, Marburg, Lassa, Junin)
Moderately easy to disseminate Cause moderate morbidity and low mortality Require specific enhancements of diagnostic capacity and enhanced disease surveillance Coxiella burnetti (Q fever) Brucella Burkholderia mallei (glanders) Alphaviruses (Venezuelan encephalomyelitis and Eastern and Western equine) Rickettsia prowazekii Toxins (Ricin, Staph enterotoxin B) Chlamydia psittaci Food safety threats (e.g.Salmonella, Shigella. E. coli O157:H7) Water safety threats (Vibrio cholerae, Cryptosporidium parvum) Category B: Second Highest Priority
Pathogens that could be engineered for mass destruction because of availability, ease of production and dissemination and potential for high morbidity and mortality and major health impact Nipah virus Hantavirus Tickborne hemorrhagic fever viruses Tickborne encephalitis viruses Yellow fever MDR TB Category C: Third Highest Priority
Characteristics of Bioterrorist Agents • Mainly inhaled - may be ingested or absorbed • Particles may remain suspended for hours • May be released silently with no immediate effect • Person-to-person spread happens for some agents • Long incubation periods mean "first responders” may be primary health care providers • Agents may be lethal or incapacitating • Vaccines & antitoxins exist for some agents
Recent Examples of Bioterrorism 1984: Salad bars contaminated with Salmonella by Rajneeshe cult members to influence local election in The Dalles, Oregon / 751 people affected (8 salad bars) 1995: Sarin nerve gas release by Aum Shinrikyo in Tokyo subway / At least 9 failed attempts to use biological weapons 1996: Pastries contaminated with Shigella by disgruntled lab worker in Dallas
Recent Examples of Bioterrorism Former Soviet Union’s extensive biological weapons program thought to have found their way to other nations Iraq acknowledged producing and weaponizing anthrax and botulinum toxin Currently, at least 17 nations believed to have biological weapons programs
Anthrax: Soviet incident An accident at a Soviet military compound in Sverdlovsk (microbiology facility) in 1979 resulted in an estimated 66 deaths downwind.
Smallpox • Variola virus • Declared eradicated by WHO in 1980 • Civilian vaccination stopped 1972, healthcare workers stopped in 1977 and CF stopped 1988 • Known stockpiles remain in CDC and Institute for Viral Preparations, Moscow • Virus spread by aerosol • Incubation period: average 12 days (7-19 days)
Last Case, Variola major Rahmina Banu, 2001 Rahmina, 1975
SMALLPOX RASH EVOLUTION Day 1 Day 2 Day 3
SMALLPOX RASH EVOLUTION Day 4 Day 5 Day 7
SMALLPOX RASH EVOLUTION Days 8-9 Days 10-14 Day 20
Smallpox • Vaccination • Within 3 days will likely prevent disease • Within 5 days is life-saving (ameliorates) • Canada has about 320,000 doses • ?long term immunity • Cell culture and oral vaccine in research • Research on antivirals also ongoing (particularly Cidofovir)
DIFFERENTIAL DIAGNOSIS: VESICULO – PUSTULARRASHES • CHICKEN POX • ERYTHEMA MULTIFORME - BULLOUS • COWPOX • MONKEY POX • HERPES ZOSTER (Shingles) - DISSEMINATED • DRUG ERUPTIONS • HAND FOOT AND MOUTH DISEASE • ACNE • IMPETIGO • INSECT BITES
“Moderately” contagious Virus not robust No natural reservoir Able to vaccinate Able to control Improved medical care Better pop’n health 30% mortality Misdiagnosis Long incubation Low level of “Immunity” Pop’n mobility Immuno-compromised Mass panic, hysteria Today’s Perspective in Canada:Pros vs Cons
Canada’s ‘search and contain’ strategy highlights: Early detection, immediate notification Immediate isolation of cases Immediate deployment of smallpox responders Immediately vaccinate all those directly exposed, all known direct contacts, all local personnel… Intensive contact tracing Rapid set up of isolation facilities Rapid set-up of local Smallpox assessment centres Assumption: In the absence of smallpox anywhere in Canada A risk of disease and death from a vaccine, no matter how small, may be unacceptable Especially when pre-attack vaccination is considered National Smallpox Contingency Plan (v.4)
US Vaccination Experience • Plan for ‘first responders” (Phase 1) • Estimated 4 million eligible; expected 500K • Vaccination in teams by Public Health • Actual uptake: about 35,000
US Vaccination Experience • Complications: • US Military: 10 cases myopericarditis/240,000 primary vaccinations; 1 cardiac arrest 5 days post vaccine • Civilian: 1case pericarditis, 1 case myocarditis, 5 cardiac ischemic events (3 MIs, 2 angina), 2 deaths (both cardiac arrest) • No cases in 110,000 military re-vacinees but 2/5 civilians were re-vacinees
US Vaccination Experience • Stockpile of ~200 million doses of cell culture vaccine + 15 million calf lymph vaccine (from 1978,1958) • Threat felt to be diminished post acute phase of the war in Iraq • Phase 2 practically is on hold although still not official (almost 4 years later)
Public Health Role • Health effects of emergencies recently highlighted • In most jurisdictions the Medical Officer of Health is part of the municipal/regional emergency response team • Have a mandated lead role in events involving biologic agents
Public Health Role • Early Detection • Mass Patient Care • Mass Immunization/Prophylaxis • Epidemiologic investigation • Communication • Command and Control
Public Health Role • Mass Fatality Management • Evacuations/sheltering (humans and animals) • Environmental Surety • Community Recovery (rapid health risk assessment, mental health etc)
Public Health Role • ‘Secondary’ responders • Key role in communication with the public for biologic emergencies • Can be liaison or link between healthcare facilities and first responders, the community • Have legal authority for many restrictive actions
Public Health Actions • Promptly investigate original case • Confirm laboratory results • Identify & interview case contacts as needed • Initiate active surveillance for additional cases • Take immediate public health prevention action as needed • Collaborate/notify MOHLTC, Health Canada as indicated • Alert local medical community/public • Determine need for Rx of contacts/health professionals • Mobilize needed assets at local, provincial, federal level • Maintain contact with case family & reporting MD
Public Health Incident Management System Chair, Board of Health Medical Officer of Health Senior Management Team Public Health Incident Manager Public Information Liaison Operations Planning Logistics Administration Claims/ Compensation Mass Vaccination/Post Exposure Prophylaxis Situation Assessment Facilities Staffing & Resource Needs Human Resources Hotline Operation Costing Reception Centre/Mass Care Procurement Resource Deployment Communications Equipment Miscellaneous Supplies Case Management/Contact Tracing Documentation Environmental Inspection/ Sampling Demobilization & Recovery Nutrition/staff accommodation Epidemiological Investigations Recovery
THE SUSPICIOUS PACKAGE • May be reported any time or any place • Since 2001 many examples have been letters delivered or packages discovered • This is a law enforcement and public health responsibility
Anthrax in the USA • 4 known letters • 11 cases of inhalational anthrax • 11 cases of cutaneous anthrax • 5 deaths from inhalational anthrax
The Suspicious Package Key Messages: • Stay calm • Remember, there is danger but there is time • Leave the package or letter but don't leave the scene
Toronto Public Health Case Definitions for Biological Events
Public Health Response • 24 hour first responder hotline • Coordination with laboratory • Developing protocols with police, fire, EMS • Links with other Health Units, provinces, Health Canada • Info to businesses, hospitals, local physicians, consulates, the public…..
Triage of Suspicious Envelopes/Packages* • A general process is outlined below, in some areas public health may play role of onsite assessment and/or transport to lab • Police notified - call 911. • Police contact local Health Unit. • Decision is made re lab testing, management of exposed individuals • Police transport material to lab. • *all environmental specimens are tested in the Central Public Health Lab
Testing in the Public Health Lab • Open and examine package in a negative pressure containment lab using level 3 protection. • Gram stain, +/- spore stains for bacteria on any material (powder, etc.) present. • Cultures, motility, biochemicals as required.
Testing in the Public Health Lab • Testing performed while maintaining chain of custody procedures and evidence documentation. • Photograph material • preserve DNA, fingerprints, handwriting • CPHL does not do chemical analysis or tell the police what the substance is.
Testing in the Public Health Lab • Send any suspicious organisms to the NML in Winnipeg for confirmation. • All samples must be treated as possible forensic evidence. • maintain chain of custody • preserve DNA, fingerprints, handwriting etc. • alert police of similar incidents from different jurisdictions
Reporting Results • Phone results to health unit and to police, within 24 - 48 hours of receipt of sample. • Written report to health unit (Medical Officer of Health) and police, within 1 - 2 weeks. • Police contacted re deposition of material • material returned to police • material destroyed by police order
Summary • Roles public health will play will vary by health unit • Will certainly have a key role in public communication • Will most often have lead for follow-up of contacts/people exposed • Will have lead role in determining of PEP/vaccination • Need to understand roles of other players in your community