Lec50 Bioterrorism

Question 1

What should you think when you see widened mediastinum with fever and sepsis?

Answer 1

inhalational anthrax

Question 2

what should you think when you see localized skin lesion with depressed black eschar?

Answer 2

cutaneous anthrax

Question 3

what should you think when you see vesicular/pustular rash starting on face and hands with all lesions same stage of development?

Answer 3

smallpox

Question 4

What properties make agents of bioterorrism dangerous?

Answer 4

• readily available
• easy to weaponize
• easy to disperse/transmit [aerosol or P2P]
• cause severe illness

Question 5

What is definition category A agents of bioterrorism?

Answer 5

• high priority agents
• easily disseminated or transmitted person to person
• high mortality/public panic/social disruption
• need special action for public health preparedness

Question 6

What are the four main category A agents of bioterrorism?

Answer 6

• anthrax [bacillus anthracis]
• tularemia [ francisella tularensis]
• plague [yersinia pestis]
• botulism [clostridium botulinum toxin]
• smallpox [variola major]
• filoviruses, viral hemorrhagic fever

Question 7

What are characteristics of bacillus anthracis?

Answer 7

• large gram pos bacilli
• spore forming
• facultative anaerobe
• non-motile
• sticky –> adheres to agar surface
• catalase positive
• boxcar morphology

Question 8

How do you get infection of bacillus anthracis?

Answer 8

• inhaled, ingested, inoculated through exposed skin

Question 9

What are the virulence factors of bacillus anthracis?

Answer 9

• capsule
• protective antigen [PA]
• edema factor [ EF]
• lethal factor [LF]

Question 10

What is anthrax edema toxin?

Answer 10

PA [protective antigen] + EF [edema factor]

Question 11

What is anthrax lethal toxin?

Answer 11

PA [protective antigen] + LF [lethal factor]

Question 12

What is anthrax lethal factor function?

Answer 12

zinc metalloprotease, stimulates inflammatory cytokine production and cell death

Question 13

What is anthrax edema factor function?

Answer 13

adenylate cyclase, increased cAMP intracellular levels

Question 14

What happens in cutaneous anthrax?

Answer 14

• direct contact organism and non-intact skin
• within 1/2 wks have local edema –> macule or papule –> ulcer –> vesicles –> black depressed exchar
• mortality in 20% without antibiotics

Question 15

What happens in GI anthrax?

Answer 15

• spores ingested
• edematous response
• huge mesenteric lymph node
• lots of tissue necrosis –> can see eschar

Question 16

What happens in inhalational anthrax?

Answer 16

• responsible for most anthrax related deaths
• inhale spore-bearing partiles
• spores phagocytosed by macrophages to mediastinal lymph node
• up to 60 days later have clinical disease
• get widened mediastinal lymph nodes and widened mediastinum

Question 17

What are symptoms of pt with inhalational anthrax?

Answer 17

• fever, nigh sweats, fatigue, respiratory

- enlarged mediastinal lymph node, widened mediastinum

Question 18

What makes anthrax a good weapon? limitations?

Answer 18

• aerosol is odorless/colorless
• spores highly stable
• disease has high case fatality rate

limitations: little [cutaneous] or no [inhalational] person to person spread

Question 19

How do you treat anthrax?

Answer 19

• penicillin, ciproflaxicin

- anthrax vaccine by military

Question 20

What is responsible for the plague?

Answer 20

yersinia pestis

Question 21

What are characteristics of yersinia pestis?

Answer 21

• biopolar “safety pin” gram neg bacilli
• slow growing
• member of etnerobacteriaceae

Question 22

What is reservoir of yersinia pestis?

Answer 22

• wild rodents

Question 23

How is yersinia pestis transmitted?

Answer 23

• via fleas or direct exposure to infect tissue or resp droplets

Question 24

What are diseases of yersinia pestis?

Answer 24

• bubonic plague [regional lymphadenitis]
• septicemia without bubo
• pharyngitis and cervical lymphadenitis
• pneumonic plague

Question 25

What are characteristics of variola virus?

Answer 25

- large DNA virus - genus orthopoxvirus - brick shaped viral structure - low infectious dose [just a few virions]

Question 26

How is variola virus transmitted?

Answer 26

person to person - via droplet nuclei or aerosols - by direct contact - by fomites

Question 27

What is pathogenesis of variola? symptoms?

Answer 27

- implants on respiratory mucosa - migrates and multiplies in regional lymph nodes - day 3/4: asymptomatic viremia w/ spread to spleen, bone marrow, lymph - day 8: secondary viremia w/ fever, toxemia, organisms in small blood vessels of dermis/oropharynx leading to pox - fever/malaise/headache/backache/delerium

Question 28

How do you differentiate chickenpox from smallpox?

Answer 28

chickenpox - palms and soles rarely involved - lesions apepar first on face or trunk - lesions in crops of different stages - no or mild prodrome - dewdrop on rose petal lesions

Question 29

How do you prevent smallpox?

Answer 29

- vaccination with vaccinia virus [cowpox] - can use for pre and post exposure prevention - -> pre-exposure protection wanes over time - -> post exposure w/4 das

Question 30

What is treatment for smallvox?

Answer 30

- vaccinia virus within 4 days of exposure - supportive care - can give cidofovir

Question 31

What makes smallpox a good agent of bioterrorism? limitation?

Answer 31

- highly susceptible population - efficient P2P spread - high case fatality - limited treatment options limitations: not in nature, only 2 known repositories [WHO labs]

Question 32

Who gets monkey pox?

Answer 32

- owners of prairie dogs due to cross contamination with gambian rats

Question 33

What are characteristics of clostridium botulinum?

Answer 33

- spore forming obligate anaerobic bacillus | - found in soil

Question 34

What is pathogenesis of clostridium botulinum? How do you get it?

Answer 34

AB toxin --> flaccid paralysis - food born from canned foods - infant from spores in honey - rarely wound botulism - inhalational botulism = terrorism agent

Question 35

What makes botulinim a good terrorism agent? limitations?

Answer 35

good: - found in nature - multiple routes of exposure - toxic lethal dose --> 1gm could kill 1 million limitations - hard to concentrate - commercially available produts have very low conc of it - not spread P2P

Question 36

What are signs of inhalational botulsim?

Answer 36

- blurred vision - drooping eyelids - slurred speach - descending paralysis - respiratory paralysis

Question 37

How do you treat inhalational botulism?

Answer 37

supportive | antitoxin

Question 38

What are properties of trancicella tularensis?

Answer 38

- poorly staining | - tiny gram neg coccobacilli

Question 39

How is tularemia transmitted?

Answer 39

- by ticks, handling animal carcasses | - can be aerosolized

Question 40

What are the 3 viral hemorrhagic fevers?

Answer 40

- ebola - marburg - lassa fever

Question 41

What is definition category B agents of bioterrorism?

Answer 41

- second highest priority agents | - moderately easy to disseminate and have morbidity but usally low mortality

Question 42

What are some examples of category B agents of bioterrorism?

Answer 42

- brucella

Question 43

What is definition category C agents of bioterrorism?

Answer 43

- third highest priority agents | - include emerging pathogens that have ease of production or potential for high morbidity/mortality

Question 44

What are examples of category C agents?

Answer 44

- nipah virus - hantavirus - MDRTB - yellow fever