Bioterrorism

Question 1

Biosecurity concerns for pathogens that would… (7)

Answer 1

Render a vaccine ineffective
Confer resistance to therapeutically useful antimicrobial
Enhance the virulence of a organism
Increase transmissibility of a pathogen
Alter the host range of a pathogen
Enable the evasion of diagnostic/detection tools
Facilitate delivery of a biological agent

Question 2

3 biological agents that are transmissible between people

Answer 2

Primary pneumonic plague (droplet)
Smallpox (contact and airborne)
Viral hemorrhagic fevers (contact and airborne)

Question 3

Bacillus anthracis

morphology, growth conditions, isolated from where, transmission, virulence factors

Answer 3

Gram positive rod
Spore forming, facultative anaerobe
Catalase and oxidase +
NON-HEMOLYTIC ON SBA
Isolated from mediastinal lymph node
Virulence factors on plasmids
No person to person transmission

Question 4

2 Baciullus anthracis virulence factors

Answer 4

pX01 = genes encoding toxins (responsible for tissue destruction and bleeding)
pX02 = genes encoding poly-D-glutamic capsule (protects against phagocytosis)

Question 5

3 forms of human anthrax

Answer 5

1. Cutaneous
2. Gastrointestinal
3. Inhalation (pulmonary)

Question 6

Cutaneous Anthrax

symptoms, mortality, specimens

Answer 6

Most common form (95%)
Inoculation of spores under skin
Painless ulcer, black center
Death 20% if untreated
Specimen of choice: vesicles fluid, blood or biopsies

Question 7

Gastrointestinal Anthrax
(transmission, symptoms, mortality, specimen)

Answer 7

Ingestion of contaminated meat
Acute GI illness, vomiting, bloody diarrhea, lesion similar to cutaneous
Mortality rate 25-60% despite treatment
Specimen of choice: blood, not stool!

Question 8

Pulmonary (inhalation) anthrax

symptoms, mortality, specimens

Answer 8

Possible presentation for bioterrorism
Initally just fever, cough, malaise
Rapid progression to high fever, dyspnea, cyanosis, hemorrhagic mediastinitis, pleural effusion
99% mortality despite treatment
Specimens: blood, pleural fluid, biopsies of mediastinal lymph nodes

Question 9

3 antibiotics to treat anthrax

Answer 9

Penicillin
Doxycycline
Ciprofloxacin

Question 10

Smallpox

other name, morphology, transmission, reservoir, vaccine, symptoms, mortality

Answer 10

Variola virus
Orthopoxvirus = large dsDNA, enveloped, complex
Transmission: contact, fomites, aerosols
Humans are reservoir, so spreads between us
Intradermal inoculaton (scarification) made from live vaccinia virus
Malaise, muscle aches, fever, rigors
High mortality if not treated (30-50%)

Question 11

What are 3 viruses transmitted by aerosols

Answer 11

Smallpox (variola virus)
Measles
Varicella

Question 12

How do you tell the difference between a smallpox rash and a chickenpox rash?

Answer 12

Smallpox: all the stages develop together, mostly on face and extremitites
Chicken: will see all stages at once (lesions, papules, vesicles), mostly on torso

Question 13

Yersinia pestis

causative agent, disease, vector, reservoir

Answer 13

Plague
Enterobacteriaceae
Fleas are vector, and rodents are reservoir

Question 14

3 Clinical presentations of the plague

Answer 14

1. Bubonic: infected lymph nodes
2. Septicemic: blood borne
3. Pneumonic: deadliest

Question 15

Bubonic plague

symptoms, mortality, specimen

Answer 15

Sudden onset of fever, malaise, myalgia
Regional lymphadenitis (buboes)
Can look for bite marks and lesions
80% become bacteremic
60% mortality if untreated
Specimen: lymph node aspirate

Question 16

If you see a big swelling on lymph nodes, what do you expect?

Answer 16

Francisella

Bubonic plague

Question 17

Septicemic Plague

acquisition, symptoms, mortality, specimen

Answer 17

Primary or secondary (from bubonic or pneumonic forms)
Systemic disease (endotoxemia, systemic inflammatory response syndrome, shock, DIC, etc)
100% mortality if untreated
Specimen: blood

Question 18

Pneumonic plague

transmission, symptoms, mortality stat, specimen, antibiotics

Answer 18

Person to person transmission by respiratory droplets
Sudden onset fever, malaise, myalgia, and pneumonia
Rapid progression to cyanosis, hemoptysis, respiratory collapse, sepsis, 100% mortality untreated
Specimen: sputum, BAL
Antibiotics: doxy or septra

Question 19

Yersinia pestis diagnosis

growth, detection

Answer 19

Clinical suspicion plus labs
Grows at 25 degC
Grows on MacConkey
Bipolar staining
PCR or DFA for detection

Question 20

2 diseases from Francisella tularensis

Answer 20

1. Pneumonic: flu like symptoms, mortality 30% if untreated, possible presentation for bioterrorism
2. Typhoidal: septicemia, possible presentation for bioterrorism

Question 21

Francisella tularensis growth conditions

Answer 21

Poorly staining gram negative cocco bacilli
Grows poorly on SBA, CHOC, thayer martin agar
Requires cysteine for growth!
Cysteine heart agar is ideal, also BCYE agar

Question 22

What can you use to treat tularemia

Answer 22

Doxycycline