Agents of Bioterrorism

Question 1

What are the categories of bioterrorism agents and a general description of the catergory?

Answer 1

Category A- easily disseminated, transmitted person-person, high mortality, potential major public health impact, panic or social disruption, special prep; B- 2nd highest, moderate morbidity, low mortality, moderate dissemination; C- 3rd, emerging pathogens that could be engineered for mass dissemination

Question 2

What are the normal epidemiologic features of anthrax?

Answer 2

resevior- herbivores (goats, sheep, cattle), wollsortter’s disease, soil- cell poor survival, spores (decades)

Question 3

What are the virulence factors of anthrax?

Answer 3

antiphagocytic capsule- poly D glutamic acid, plasmid encoded (pX02), endotoxins- PA- protective Ag (binding site non-toxic), EF- edema factor (andenylate cyclase), lethal factor (protease), plasmid encoded (pX01); non-encapsulated is not virulent, 1 plasmid for capsule and 1 for toxin

Question 4

Describe the mechanism of anthrax.

Answer 4

PA binds cell receptor, 7 PAs bound to receptor form a big compound and will bind 3 of either EF or LF (any combo), endocytosis, acidification of endosome by host cell casues secretion of EF/LF, EF- inc cAMP causing inhibition of phagocytosis and edema, LF- dec. MAPK-> apoptosis and cytokine production, necrosis and hypoxia

Question 5

What are the types of anthrax? Which method is bioterrorism delivery?

Answer 5

cutaneous, GI, and inhalation (pulmonary, bioterrorism)

Question 6

what are the features of cutaneous anthrax? GI?

Answer 6

most common (esp developing countries), septicemia rare, mortality <1%; extremely rare (none in US)

Question 7

What are the features of inhalation (Pulmonary) anthrax?

Answer 7

spore germinate in lungs, not communicable, onset flu-like- SOB, sweats, fever/chills, fatigue, non-prod. cough, N/V, chest/muscle pain, headache; mediastinal widening on CXR, septicemic spread, rapid onset death 3-7d, resp fail, shock, meningitis, untreated 100% fatal

Question 8

How is anthrax diagnosed?

Answer 8

blood/CSF culture- medusa head colonies, phenotypical or biochemical characteristics, PCR (RT-PCR), ELISA, or DFA; purple on outside, capsule doesn’t stain

Question 9

What us the therapy for anthrax?

Answer 9

ciprofloxacin or tetracycline; unless genetically selected against, then good chance gram + antibiotic will work

Question 10

Who gets an anthrax vaccine?

Answer 10

military, lab workers; new recombinant vaccine under way, current vaccine poor

Question 11

what are the general features of Yersinia pestis?

Answer 11

plague, enterobacter., “safety pin” bipolar staining, single most significant disease in W. civilization, killed 1/3 pop, “Black death”

Question 12

what is the epidemiology of Y pestis in US? Sylvatic plague? Urban plague?

Answer 12

SW, fleas feeding on squirrels, prairie dogs, chipmunks, etc; S- flea to rodent to flea to rodent, humans get close to sick rodent and flea hops to human; U- rodent (wild) to flea to rodent (urban-rat) then flea to human; Y pestis grows in flea, regurgitated into host with next blood meal

Question 13

What are the virulence factors of Y. Pestis?

Answer 13

many!!! big component of disease is the cytokine storm

Question 14

What is the presentation, signs and symptoms of bubonic plague?

Answer 14

1-7d incubation after flea bite, fever, chills, headache, exhaustion, spreads to lymph nodes (unilateral), develop bubo (enlarged tender lymph node) esp groin, neck and armpit, skin hemorrhages- capillaries = black death, shock, death, mortality 8% treated >50% untreated, no person to person

Question 15

How is pneumonic plague transmitted?

Answer 15

flea to rodent cycle, flea to human-> bubonic-> systemic spread to lungs (few patients), then aerolosized in lungs and spread out (person to person)

Question 16

What is the presentation, signs and symptoms of bubonic plague? (bioterrorism)

Answer 16

1-4d incubation after inhalation (1-10 org), flu-like symp. w/ high fever, cough/bloody sputum, shock, death, mortality ~100% untreated and ~15% treated, person to person transmission

Question 17

What is the drug of choice for confirmed plague?

Answer 17

streptomycin (difficult to get but other similar options exist)

Question 18

How is plague prevented?

Answer 18

no vaccine, sylvatic/urban: bug repellant, pre-exposure prophylaxis AB, pneumonic- droplet precautions

Question 19

What are the general features of Franciscella tularensis?

Answer 19

zoonotic gram (-) coccobacillus, obligate aerobe, facultative intracellular w/ macrophage (other ~10), causes rabbit fever, reservoir- rabbits, sheep, squirrels, deer etc, can be in food/water contaminated, or aerosol- bioterrorism

Question 20

What are the tularemia types?

Answer 20

ulceroglandular (most common), glandular, occuloglandular, oropharyngeal and GI, pneumonic, and typhoidal

Question 21

What are the signs and symptoms with ulceroglandular Tularemia?

Answer 21

skin (scratch or abrasion) or insect/tick bite, ulcer at site of infection, swollen painful lymph glands, fever, chills, headache, exhaustion

Question 22

What are the signs and symptoms with glandular Tularemia?

Answer 22

swollen painful lymph glands, fever, chills, headache, exhaustion

Question 23

What are the signs and symptoms with oculoglandular Tularemia?

Answer 23

eye pain/ redness/ swelling/ discharge, ulcer inside eyelid

Question 24

What are the signs and symptoms with oropharyngeal Tularemia?

Answer 24

digestive tract, fever, pharyngitis, mouth ulcers, vomiting, diarrhea

Question 25

What are the signs and symptoms with pneumonic Tularemia?

Answer 25

inhalation; cough, chest pain, difficulty breathing, respiratory failure, death, most likely bioterror mode, 30-60% fatal if untreated- respiratory failure

Question 26

What are the signs and symptoms with typhoidal Tularemia?

Answer 26

consequence of any primary exposure leading to septicemia, high fever, extreme exhaustion, vomiting diarrhea, splenomegaly, hepatomegaly, and pneumonia

Question 27

How is tularemia diagnosed?

Answer 27

workup in BSC, presumptive ID: gram stain, slow growing colonies on CHOC and none on BAP, oxidase and urease (-), weak catalase (+), confirmation PCR at Lab response network, reportable agent, document destruction of isolate

Question 28

How is tularemia treated? prevented?

Answer 28

DOC: gentamicin (streptomycin), fatal if not treated 30-60%; vaccine- investigational but available w/ informed consent

Question 29

what are the virulent features of Clostridium Botulinum Toxin?

Answer 29

most lethal substance known, aerosolized- 200g could kill entire US, neurotoxin- prevent ACh release, muscle contraction both voluntary and diaphragm

Question 30

What is the presentation, signs, and symptoms of botulism?

Answer 30

onset 12-36hrs, early- dry mouth, blurred/double vision, late- symmetric descending weakness, diplopia, dysphagia, dysphonia, respiratory paralysis, death

Question 31

What mechanisms can be employed for botulinum toxin in bioterrorism?

Answer 31

food/water, aerosol- inhalation= 100x more potent

Question 32

How infectious is Burkholderia mallei? Routes and symptoms with each?

Answer 32

Glanders-Low infectious dose
Symptoms: Cutaneous-multiple abscesses; Eye, nose, other mucous membranes-mucopurulent discharge; Pulmonary/systemic-fever, myalgia, headache, chest pain, diarrhea

Question 33

What does Burkeholderia pseudomallei cause?

Answer 33

Melioidosis (glanders-like)