• particle diameter
  • aerosole spray/cloud: 5-17 microns
  • 1-5 microns absorbed in alveoli
  • greater than 5-10 is filtered out or deposited in URT

• ease of dissemination
• potential for major public health impact
• requirements for public health preparedness

• severe disease in a healthy patient
• increased number of patients with fever, rash, respiratory or GI symptoms, or sepsis
• large number of rapidly fatal respiratory cases
• increasing number of ill or dead animals
• rapid rise and fall in epidemic curve
• multiple patients presenting from a similar location
• endemic disease at an unusual time of year

• severe gastroenteritis
• fatal pneumonia in healthy patient
• widened mediastinum with fever
• rash with synchronous vesicular/pustular lesions
• acute neurologic illness with fever
• advancing CN palsy with weakness

• easily disseminated/transmitted
• high mortality rates
• potential for major public health impact
• potential for public panic and social disruption
• special action for public health preparedness
• greatest risk agents

• anthrax
• plague
• smallpox
• tularemia
• VHF's
• botulism
• ricin

• Bacillus antracis
  • spore forming gram positive bacteria
• epidemiology
  • zoonotic disease of herbivores
  • occurs naturally in humans handling contaminated animal products
  • transmission- skin abrasion, inhalation, consume infected meat
• cause dermatologic, GI, and inhalation illness

• commonly on upper extremities
• papule followed by vesicle
• vesicle dries to form black scab (eschar)
• mortality
  • 1% w/tx
  • can be systemic w/20% mortality

• rare
• transmission- acquired through ingestion of contaminated undercooked meat
• symptoms
  • oral/esophageal ulcer can progress to lymphadenopathy and edema
  • severe sepsis

• greatest spread
• greatest number of fatalities and incapacitation

• clinical course
  • nonspecific prodrome of fever, SOB, cough, chest discomfort
  • brief period of improvement possible
  • after 2-4 days, resp failure w/ hemodynamic collapse
• mortality: 50-95%

aka woolsorter's disease

• chest X ray
  • widened mediastinum
  • relative sparing of lung tissue
  • can see even: mediastinum, pleural effusion
• gram stain blood, blood culture on routine media or ELISA late
• look for hemorrhagic meningitis
• leukocytosis

• penicillin is tx of choice
• CDC advice initial therapy with doxycycline or ciprofloxacin until sensitivities available
• px w/cipro or doxycycline for at least 60 days in exposed individuals
• close medical surveillance
• licensed vaccine approved by FDA

• causative agent- Yersinia pestis (gram negative rods)
• difficult to weaponize but:
  • it would probably be used as aerosol causing pneumonic, not bubonic plague
• very high mortality

• transmission (zoonosis of rodent host and flea vector)
  • inhalation of aerosoles (human to human)
  • flea bite or direct contact with infected fluids/tissues
• multiplies in lung parenchyma
• spreads to mediastinal lymph nodes and bloodstream
• lymphatic infection leads to bubonic form

• severe febrile illness
• headache
• myalgias
• malaise
• chills
• prostration
• GI symptoms

• clinical course
  • inguinal, axillary, and cervical lymphadenopathy
  • tender non fluctuant lymph nodes
  • 2-6 dys incubation
• fatality rate for untreated cases is 50%

• secondary to septicemic plague or inhalation of infectious droplets
• clinical course
  • incubate 1-3 dys
  • fever, productive cough, hemoptysis, chest pain

• chest xray: bilateral infiltrates or lobar consolidation
• gram stain of sputum and lymph node aspirates
• Wright/Giemsa stain shows "safety pin" pattern
• cultures- fried egg appearance after 48-72 hrs

• IM streptomycin
• buboes resolve after 10-14 dys
• chloramphenicol for meningitis
• tx mildly ill pts with doxycyclin
• unprotected direct contacts should get post exposure px with doxycycline BID for 6 days

• clinical presentation occurs 12-72 hrs after exposure
• bulbar symptoms
  • diplopia
  • dysarthria
  • dysphagia
• severe descending paralysis
• respiratory failure may ensue

• causative agent- Clostridium botulinum
  • spore forming
  • anaerobic bacillus
• transmit as bioterrorist agent via food and air

• antitoxin to prevent progession or shorten illness course
• no indication of px antitoxin
• supportive care
• no benefit of antibiotics

• orthopoxvirus
• ssDNA

• no natural reservoir but
• great ease of production and aerosolization (10-100 particles needed for infection)
• virus does exist outside certain laboratories and could be used to cause bioterrorism

• variola major (most common)
• variola minor- milder and less than 1% mortality (dx base on assessment of outbreak)
• hemorragic and malignant smallpox- early hemorrhagic form 100% fatal

incubation 12-14 days during which no viral shedding occurs and patient is not contagious

• flu like symptoms
• after 2-3 days characteristic rash in centrifugal distribution
  • involves palms and soles
• mucous membrane lesions
• papules to macules to vesicles
• scabbing after 8-14 days

• severe varicella
• human monkeypox
  • patients have lymphadenopathy
  • not easily transmitted human to human
• erythema multiforme
• measles
• molloscum contagiosum in HIV patients

• vaccine up to 96 hrs post exposure and prior to appearance of rash can prevent disease severity
• no effective tx
• supportive care

• disease does not spread rapidly (requires close contact)
• retains immunity up to ten yrs
• vaccinate close contacts and patient isolation may contain the outbreak
• since vaccine stopped in 1980, our current population is not immune

• eczema vaccinatum- erruption at site of eczema that spread to healthy skin
• progressive vaccinia- in immune deficient patients, failure of local lesion to heal, spread of secondary lesions, death
• generalized vaccinia- healthy patients, good progrnosis
• postvaccinial encephalitis- high mortality
• adverse cardiac events
  • myocarditis rate increased
  • no causal association for cardiac ischemic events after vaccination

• 3-5 days: papule
• 5-8 days: vesicle
• 14-21 days: scab
• formation of papule, vesicle, ulcer, or crusted lesion surrounded by induration indicates successful "take"

• Francisella tularensis- small gram negative coccobacillus
• transmission- resp. exposure via aerosol cause typhoidal and pneumonic tularemia

aka rabbit fever

• 1-21 day incubation
• nonspecific acute febrile illness
• forms
  • typhoidal
  • ulceroglandular
  • glandular
  • oculogladular
  • orapharyngeal
  • pneumonic

• ulceroglandular form
• inoculation of skin or mucous membrane by blood of body fluids of infected animals
• fever, chills, headache, malaise, ulcerated skin lesion, painful regional lymph node inflammation