Chapter 12: Yersinia, Francisella, Brucella, and Pasteurella

Question 1

What do Yersinia, Francisella, Brucella, and Pasteruella have in common?

Answer 1

All gram - rods
Zootinic diseases
Very virulent, able to penetrate any body area or be inhaled
Facultative intracellular organisms: migrate to regional LN, set up infection, move to bloodstream and other organs (liver, spleen, lungs)

Question 2

Yersinia pestis causes what?

Answer 2

the bubonic plague
Southwestern U.S
Transmission: rats/fleas
Virulence: F1 (capsular), V and W resist destruction after phagocytosis

Question 3

What are the symptoms of the bubonic plague?

Answer 3

Nodes swell like eggs and become hot, red, and painful
Fever and headache
Hemorrhages under the skin ->blackish discoloration
Death

Question 4

What does Francisella tularensis cause?

Answer 4

Tularemia: disease that resembles bubonic plague
Ulceroglandular and pneumonic diseases
Oculoglandular tularemia (eyes)
Typhoidal tularemia (GI tract)

Question 5

Transmission of Fracisella tularensis?

Answer 5

Rabbits, ticks and deerflies

Question 6

Ulceroglandular tularemia

Answer 6

After a bit from an infected rabbit, tick or deerfly a well-demarcated hole in the skin with a black base develops
Fever and systemic symptoms develop
Local LN swell, red, painful

Question 7

Pneumonic tularemia

Answer 7

Aerosolization of bacteria during skinning and evisceration of an infected rabbit or hematogenous spread from the skin to the lungs can lead to a lung infection

Question 8

What are the Brucella species?

Answer 8

based on the animals they infect:
Brucella melitensis (goats)
Brucella abortus (abortion in cows)
Brucella suis (pigs)
Brucella canis (dogs)

Question 9

Transmission of Brucella to humans

Answer 9

Direct contact with infected animal meat or aborted placentas or ingestion of infected milk products
Pts most likely a worker in meat-packing industry, a veterinarian, farmer or traveler who drinks milk

Question 10

How does Brucella cause disease?

Answer 10

Penetrates the skin, conjuctiva, lungs, or Gi tract

Lymphatic spread, faculative intracellular growth in Mo, and blood and organ invasion

Question 11

What are the symptoms of Brucellosis ?

Answer 11

Systemic with fever, chills, sweats, loss of appetite, backache, headache, and sometimes lymphadenopathy
Fever peaks in the evening and slowly returns to normal by morning (Undulant fever)
Symptoms lasts from months to years

Question 12

Pasteurella multocida

Answer 12

Gram - zoonotic organism but is NOT a facultative intracellular organism
Colonizes the mouths of cats

Question 13

What causes the most frequent wound infection following a cat or dog bit ?

Answer 13

Pasteruella multocida