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PU 430PU 430Unit 5
Chapters 2 and 3
Bioterrorismhttp://www.youtube.com/watch?v=2t_MsSO9qRk
Chapter Two
Basic Facts About Bioterrorism Threats Bioterrorism is the use or threatened use of
biological agents as weapons of terrorCurrent U.S. laws make the threat alone a
severe crimeThe biological material used may be lethal or
nonlethal, a common bacteria or virus, the toxic by-product of a pathogen, a rare organism, or even a specially engineered organism, never before diagnosed or treated
These acts are intended to instill fear in the targeted population in support of terrorist goals
Organisms or other biological materials can be released in the air, or placed in food or water sources
Advantages of Biologics Advantages of Biologics as Weaponsas Weapons
Easy to obtainInexpensive to producePotential dissemination over large
geographic areaCreates panicCan overwhelm medical servicesSusceptible civilian populationsHigh morbidity and mortalityDifficult to diagnose and/or treatSome are transmitted person-to-person via
aerosol
Routes of InfectionRoutes of Infection Skin (cuts, abrasions, mucosal membranes) Gastrointestinal
◦ Food Potentially significant route of delivery Secondary to either purposeful or accidental
exposure to aerosol◦ Water
Capacity to affect large numbers of people Dilution factor Water treatment may be effective in
removal of agents Respiratory
◦ Inhalation of spores, droplets & aerosols◦ Aerosols most effective delivery method◦ 1-5 droplet most effective
Medical ResponseMedical Response Pre-exposure
◦ active immunization◦ prophylaxis◦ identification of threat/use
Incubation period◦ detection and diagnosis◦ active and passive immunization◦ antimicrobial or supportive therapy
Overt disease◦ diagnosis◦ treatment
may not be available may overwhelm system may be less effective
◦ direct patient care will predominate
BioterrorismBioterrorism::Who are 1st Responders?Who are 1st Responders?
Primary Care PersonnelHospital ER StaffEMS PersonnelPublic Health ProfessionalsOther Emergency Preparedness
PersonnelLaboratory PersonnelLaw Enforcement
ScenariosScenariosOvert Event
◦Announced◦Patients Fall ill or Die (Increased Morbidity and Mortality)
◦Microorganisms Unconfirmed◦Hoaxes Assumed to be Real
ScenariosScenariosCovert Event
◦No Prior Warning - Unannounced◦Patients Fall ill or Die from Causes of Unknown or Unusual Origin
◦Unusual Cluster(s) of Cases - May be Geographically Distributed
◦Undetermined Causative Agent
U.S. Bioterrorism Preparedness Controversies
Bioterrorism preparedness activities include:◦The development & practice of a mass
emergency distribution of pharmaceuticals◦Risk communication training◦Incident Command System training for public
health & healthcare workers
Controversy surrounds many issues, including:◦Vaccinations & antibiotics◦The potential for increasing bioterrorism &
biocrime risks◦Funding of public health programs
Categorization of Threats
Category A pathogens - High priority organisms & toxins posing the greatest threat to public health
Category B agents - Fairly easy to disperse but have lower morbidity & mortality than the Category A agents & can be successfully addressed
Category C agents - Emerging infectious organisms that could become easily available at some point in the future & used as a weapon
Health Threats: Category A Organisms
Anthrax (Bacillus anthracis) – considered by many to be the perfect biological weapon Botulism (Clostridium botulinum toxin) - regarded as the most potent poison in the worldPlague (Yersina pestis) - without quick antibiotic treatment, can cause death in several daysSmallpox (Variola major, Variola minor) - the most destructive infectious disease in human historyTularemia (Francisella tularensis) - highly infectious for individuals directly exposed to the organisms, but is not spread from person to personViral Hemorrhagic Fevers (Filoviruses,Arenaviruses,
Bunyaviruses, & Flavivruses) – have potential lethality & infectiousness at low doses when delivered as an aerosol
Anthrax: Current Issues in the U.S.
Anthrax remains an endemic public health threat through annual epizootics.
B. anthracis is one of the most important pathogens on the list of bioterrorism threats
Aerosolized stable spore form Human LD50 8,000 to 40,000 spores,
or one deep breath at site of releasehttp://www.youtube.com/watch?v=4IxFU_itIUE
Exposure Situation Management: Exposure Situation Management: B. anthracisB. anthracis in Envelope in Envelope
Antimicrobial prophylaxis for those potentially exposed
Environmental samples◦Surface swabs◦Nasal swabs of potentially exposed persons (if <7 days)
Refine list of potentially exposed persons◦Not exposed: stop treatment◦Likely exposed: continue treatment for 60 days total
Anthrax: Post-Anthrax: Post-Exposure TreatmentExposure Treatment
Start oral antibiotics as soon as possible after exposure◦Ciprofloxacin or Doxycycline or
Amoxicillin/Penicillin (if known PCN sensitive)
Post-Exposure Treatment Post-Exposure Treatment (continued)(continued)
Antibiotics for 60 days without vaccine Antibiotics for 30 days with 3 doses of
vaccine (animal studies) Long-term antibiotics necessary
because of spore persistence in lung/lymph node tissue
Anthrax: VaccineAnthrax: Vaccine(continued)(continued)
Current U.S. vaccine (FDA Licensed) - continued◦FDA approved for 6 dose regimen over 18
months◦3 dose regimen (0, 2, and 4 weeks) may be effective for post-exposure
treatment (animal studies)◦Limited availability
Prevention
Prevention of bioterrorism
Public Health Security & Bioterrorism Preparedness & Response act of 2002
The Pandemic Preparedness & Response Act
FOODBORNE FOODBORNE BOTULISMBOTULISM
Infective dose: 0.001 g/kgIncubation period: 18 - 36 hoursDry mouth, double vision, droopy
eyelids, dilated pupilsProgressive descending bilateral
muscle weakness & paralysisRespiratory failure and deathMortality 5-10%, up to 25%
Level A ProceduresLevel A Proceduresfor Botulism Eventfor Botulism Event
Properly collected specimens are to be referred to designated testing laboratories
Prior to the shipment of any botulism-associated specimen, the designated laboratory must be notified and approved by the State Health Department
Plague: Overview Plague: Overview
Natural vector - rodent flea
Mammalian hosts◦rats, squirrels, chipmunks,
rabbits, and carnivoresEnzootic or Epizootic
CDC: Wayson’s Stain of Y. pestis showing
bipolar staining
Plague EpidemiologyPlague Epidemiology
Three Clinical Types:◦bubonic (infected lymph nodes)◦septicemic (blood-borne organisms)◦pneumonic (transmissible by aerosol;
deadliest)
Plague: ProphylaxisPlague: ProphylaxisBubonic contacts
◦If common exposure, consider oral Doxycycline, Tetracycline, or TMP/SMX for 7 days
◦Other close contacts, fever watch for 7 days (treat if febrile)
Plague: ProphylaxisPlague: Prophylaxis(continued)(continued)
Pneumonic contacts (respiratory/droplet exposure)◦Consider oral Doxycycline, Tetracycline,
or TMP/SMX◦Continue for 7 days after last exposure
Vaccine no longer manufactured in U.S.◦Not protective against pneumonic plague
Detection
Limiting the impact of a bioterrorism attack requires healthcare providers with sufficient training & support to remain diligent
Regular disease surveillance includes:◦ Mandatory disease reporting by local healthcare
providers◦ Data entry & analysis by local or regional public health
agencies◦ Additional analysis, reporting, & allocation of needed
resources by state & federal public health agenciesOther forms of surveillance include
environmental monitoring & standoff detection
Plague:Plague:Medical ManagementMedical Management
Supportive therapyIsolation with droplet precautions for
pneumonic plague until sputum cultures negative
Antibiotic resistant strains have been documented
Plague: Clinical FormsPlague: Clinical FormsBubonicBubonic
Bubonic ◦Inguinal, axillary, or cervical lymph nodes most
common◦80% can become bacteremic◦60% mortality if untreated
USAMRICD: Inguinal/femoral buboes
Plague: BubonicPlague: BubonicIncubation: 2-6 daysSudden onset headache,
malaise, myalgia, fever, tender lymph nodes
Regional lymphadenitis (Buboes)
Cutaneous findings◦possible papule, vesicle, or
pustule at inoculation site◦Purpuric lesions - late
Smallpox: OverviewSmallpox: Overview1980 - Global
eradicationHumans were only
known reservoirPerson-to-person
transmission (aerosol/contact)
Up to 30% mortality in unvaccinated
CDC: Electron micrograph of Variola major
Smallpox: Smallpox: Clinical FeaturesClinical Features
Prodrome (incubation 7-17 days)◦Acute onset fever, malaise, headache, backache, vomiting
◦Transient erythematous rash
Level A ProceduresLevel A ProceduresSmallpox virusSmallpox virus
Rule out chickenpox (PCR)! Specimen of choice is lesion material from
pustulesContact your State Public Health
Laboratory for guidance
Smallpox:Smallpox:Current VaccineCurrent Vaccine
Made from live Vaccinia virus
Intradermal inoculation with bifurcated needle (scarification)◦Pustular lesion/induration
surrounding central scab/ulcer 6-8 days after vaccination
WHO: Smallpox vaccine vials
Smallpox:Smallpox:Medical ManagementMedical Management
Strict respiratory/contact isolation of patient◦Patient infectious until all scabs have
separatedNotify public health authorities immediately for
suspected caseIdentify contacts within 17 days of the onset of
case’s symptoms
Immediate Actions
With quick identification of the biothreat agent & population at risk, there is a window of opportunity for prophylactic treatmentDecisions must be made rapidly & the response needs to begin immediatelyCommunication must be quickly established with the population at riskThose working in healthcare, public health, & the first response community need to be provided with detailed instructions on how to respond
BioterrorismBioterrorism::What Can Be Done?What Can Be Done?
AwarenessLaboratory Preparedness Plan in placeIndividual & collective protectionDetection & characterizationEmergency response Measures to Protect the Public’s Health
and SafetyTreatmentSafe practices
Recovery
Clean-up will not be difficult for most pathogenic organisms, with the notable exception of anthrax
Federal Insecticide, Fungicide, & Rodenticide Act (FIFRA)
◦The Environmental Protection Agency has established a listing of “antimicrobial products” to ensure that effective cleaning agents are used
Bombings and Explosions
Chapter Three
Introduction
Between 2006 & 2007, the death toll related to bombs increased by 30% & the number of suicide bombings increased by approximately 50%
Today’s bombers often want to generate as many civilian casualties as possible & are acquiring the technologies & methods to reach that objective
Health Threat
Four categories have been established to aid in the understanding of the complex assortment of injuries associated with explosions & provide structure for the triage process:
◦ Primary blast injuries
◦ Secondary blast injuries
◦ Tertiary blast injuries
◦ Quaternary blast injuries
Prevention
1.) Physical Security
2.) Threat Detection & Identification
Immediate Actions
If a threat necessitates an evacuation from a building: ◦Everyone at risk must be evacuated
immediately to a safe distance◦Occupants should quickly collect personal
items so they are not among the possible threats needing to be assessed by bomb technicians
◦Elevators should not be used◦There should be a rallying point away from the
building for a head count
Health & Medical Response
The Centers for Disease Control & Prevention have established several essential concepts that caregivers need to keep in mind concerning provision of care to those injured in explosions
It is important for all the first responders to be aware of risks when approaching a potential bomb scene
It is important to consider the possibility of residual explosive material
Local public health agencies also have an important role in long-term monitoring & follow-up of survivors