25a Plague, Tularemia, Brucellosis Vignette

Question 1

What is the Tx of…
Y. pestis?
F. Tularensis?
Brucella?

Answer 1

Y: Streptomycin, tetracycline or chloramphenicol

F: Streptomycin

B: Tetracycline with rifampin

Question 2

Detail: What are examples of Category A bioterrorism agents?

Answer 2

Anthrax
Botulism
Plague (Yersinia pestis) –animal reservoir
Small pox
Tularemia (Francisella tularensis) – animal reservoir
Viral hemorrhagic fevers (filoviruses etc.)

Question 3

Detail: What are examples of Category B bioterrorism agents?

Answer 3

Brucellosis (Brucella) – animal reservoir Salmonella 
  Shigella     E. coli 0157:H7
  Glander (B. mallei)
Meliodosis (B. pseudomallei)
  Psittacosis (Chlamydia psittaci
 Q fever (Coxiella burnetii)
  Ricin toxin (castor beans)
Staphylococcal enterotoxin B
  typhus fever (Rickettsia prowazekii)
  viral encephalitis (e.g. equine encephalitis)
  Vibrio cholerae
Cryptosporidium parvum

Question 4

Detail:What are examples of Category C bioterrorism agents?

Answer 4

Emerging viruses (e.g. Hantavirus)

Question 5

EXAM: What are Category A and B bioterrorism agents that have an animal reservior?

Answer 5

Yersinia pestis (plague)
Francisella tularensis (tularemia)
Brucellosis (brucella)

Question 6

What is the morphology and stain of…
Y. pestis
F. tularensis
Brucella

Answer 6

Y. pestis: Pleiomorphic Gram- rods,
Giemsa and Wayson stains positive with safety pin appearance due to bipolar staining, grey-white non hemolytic, Enterobacteriaceae

F. tularensis: Pleiomorphic Gram-rods, needs cysteine for growth, survives for weeks at low temperature, grayish white non-hemolytic colony

Brucella: Small pleiomorphic Gram- rods, slow growing, needs 10% CO2, three major pathogenic species, white non-hemolytic colonies

Question 7

What is the epidemiology of…
Y. pestis
F. tularensis
Brucella

Answer 7

Y. pestis: Zoonotic disease among rodents, accidental human infection, rare in US

F. tularensis: Zoonotic diseases among rodents and rabbits, rare in US

Brucella: Zoonotic disease (goat, cattle and pig)

Question 8

What is the transmission vehicle of…
Y. pestis
F. tularensis
Brucella

Answer 8

Y. pestis: Rat flea – transmit during blood meal, direct contact of infected tissues or respiratory droplets

F. tularensis: Tick bite, contact with infected tissues or ingestion or inhalation

Brucella: Contaminated milk, direct tissue contact or inhalation

Question 9

What is the CLINICAL presentation of…
Y. pestis
F. tularensis
Brucella

Answer 9

Y. pestis: Bubonic plague, Pneumonia plague, septicemic plague

F. tularensis: Ulceroglandular tularemia (skin and lymph node), Tularemia pneumonia and typhoidal tularemia (bacteremia)

Brucella: Chronic fever, subtle illness, enlarged nodes, spleen and liver, occasional osteomyelitis and endocarditis

Question 10

What is the Dx of
Y. pestis
F. tularensis
Brucella

Answer 10

Y. pestis: Culture (aerosol infectious), or more commonly fluorescent antibody staining or a rise in antibody titer

F. tularenis: Danger to culture in the lab (10-50 organisms required for infection), fluorescent antibody staining preferable or rise in antibody titer

Brucella: Growth of organism (from tissue biopsy or bone marrow), rise in antibody titer

Question 11

What is the histology of…
Y. pestis
F. tularensis
Brucella

Answer 11

Y. pestis: Safety pin appearance on Giemsa or Wayson stain

F. tularensis: Granuloma in tissues

Brucella: Granuloma formation in tissues

Question 12

What is Tx of…
Y. pestis
F. tularensis
BrucellaY

Answer 12

Y. pestis: Streptomycin, tetracycline or chloramphenicol

F. tularensis: streptomycin

Brucella: tetracyclin with rifampin