Micro- Anthrax and Smallpox Flashcards
What is a category A bioterror agent?
- high mortality rate
- easily transmissible person-to-person
- special public health actions are necessary
- causes social disruption
What is a category B bioterror agents?
- moderate rates of illness but low mortality
2. moderately easy to disseminate
What is a category C bioterror agent?
- emerging infectious agent
- possible to produce easily
- potential for high morbidity and mortality
What 3 bacteria are “category A” bioterror agents?
- anthrax [bacillus anthracis]
- plaque [yersinia pestis]
- tularemia [francisella tularensis]
What 2 viruses are category A bioterror agents?
- smallpox [variola major]
2. Lassa, Marburg, Ebola, Denque
What toxin is category A bioterror agent?
Botulism/botulinum toxin
What are the category B bioterror agents?
- Q fever [coxiella burnetti]
- Brucelliosis
- Glanders/Meliodosis- burkholderia
- Psittacosis- chlamydia psittaci
- typhus [rickettsia prowazekii]
- food and waterborne pathogens [shigella, salmonella, campy]
What are the category C bioterror agents?
- MDR and XDR TB
- Viruses
- nipah
- hanta
- yellow fever
What are the advantages of biologics as weapons?
- easy to obtain
- inexpensive
- can be disseminated over large geographic areas
- perpetrator escapes easily
What is the “ideal microbe” for bioterror?
- infectious as aerosol
- stable in the environment
- susceptible population
- spread person-to-person
- high morbidity and mortality
- difficult to diagnose or treat
What are the 2 aerobic gram positive rods?
- bacillus
2. cornybacterium
What are the three inoculation sites for anthrax?
- inhalation
- cutaneous
- gastrointestinal
How do you acquire cutaneous anthrax?
What happens following inoculation?
It is acquired by contact with material contaminated with SPORES [textile from animal skin or hair, raw hides, wool]
After inoculation:
- development of papular lesion
- become vesicular with surrounding edema
- form a black eschar
It is painless
How do you acquire GI anthrax?
What is incubation period?
What is the presentation of disease?
What is the fatality rate?
Eating contaminated meat that is undercooked.
Incubation is hours to 7 days while spores germinate in your intestines.
Presents with:
- bloody diarrhea
- fever, vomiting
Case fatality is 25-75%
Describe inhalation anthrax. How is it acquired? How long is incubation? What are the initial symptoms? What are the later symptoms?
Inhalation of spores
Incubation 3 to greater than 40 days
Begins with non-specific flu-like illness
-fever, myalgia, headache, chest discomfort
*May have a period of transient improvement [RED]
Rapid deterioration to high fever, dyspnea, shock
What is the pathogenesis of inhalation anthrax?
- inhale 2micron particles
- ingested by alveolar macrophages which move to hilar lymph nodes
- germination, production of anthrax toxin in the lymph nodes
- Hemorrhagic necrosis of nodes and mediastinum
- Gelatinous pleural effusion with atelectasis
- seeding of other organs
- hemorrhagic meningitis
What are the 2 main virulence factors of B. anthracis?
- capsule
2. anthrax toxin
What are the inhalation anthrax major signs?
- fever, tachycardia, tachypnea
- toxic appearance
- signs of pulmonary consolidation or pleural effusion
- may NOT have pulmonary infiltrates since germination of spores is in the nodes in the mediastinum and NOT the lungs
Why may there not be pulmonary infiltrates in inhalational anthrax?
Because germination of the spores takes place in the nodes of the mediastinum and not in the lungs [RED]
How is the diagnosis of inhalational anthrax made based on :
- suspicion [RED]
- proof [RED]
Suspicion:
- widened mediastinum on CXR [RED]
- hemorrhagic mediastinal nodes on CT
- no rhinorrhea or conjunctivitis; pharyngitis unusual
Proof [RED]
- culture, PCR or immunohistochemistry of nasopharyngeal swab, sputum, pleural fluid
- Blood culture
- Gram stain and culture of CSF
- Serology - IgG to protective antigen
What is treatment for inhalation anthrax [x60days]?
ciprofloxacin OR doxy [not effective against meningitis]
PLUS
1 or 2 additional antimicrobials [ vanc, penG, others]
What is the treatment for cutaneous anthrax [x7-10 days, unless aerosol exposure]
oral Cipro or Doxy
What is anthrax chemoprophylaxis?
How long is it given
Disease doesn’t begin until spores germinate [maybe weeks later]
If the person may have been exposed, treat them for a long time [over 60 days] with cipro or doxy p.o.
Who receives the anthrax vaccine?
How is it delivered?
Vaccine is given to military personnel and occupational exposures.
It has protective antigen and requires multiple injections over a period of weeks.