Lesson 8d: Yersinia species

Question 1

are found in the intestinal tract of wild mammals, birds and domestic animals as reservoirs of infection or act as amplifier host and may also transfer the organisms mechanically

Answer 1

Yersinia pseudotuberculosis and Y. enterocolitica

Question 2

important reservoir of Y. pestis

Answer 2

Wild rodents

Question 3

Y. pestis, maintains a sylvatic cycle in association especially with?

Answer 3

oriental rat fleas, Xenopsylla cheopis

Question 4

Both organisms can grow in a wide temperature range (5 to 42°C) and survive for long periods in cool wet conditions

Answer 4

Yersinia species

Question 5

facultative intracellular organisms

Answer 5

Yersinia species

Question 6

the three pathogenic yersinia species possess virulence factors, encoded on plasmid and chromosomes, such as?

Answer 6

invasin and adhesion/invasion proteins and have an affinity for integrins on cell surfaces

Question 7

key virulence factor of all three pathogenic yersinia species is ______________, which encoded on a plasmid called _________.

Answer 7

type III secretion system (TTSS)

pYV

Question 8

allows the effector proteins (Yersinia outer proteins pr Yops) to be translocated into host cells

Answer 8

pYV

Question 9

interfere with phagocytosis and production of reactive oxygen species

Answer 9

Yops

Question 10

is more invasive than Y. pseudotuberculosis and Y. enterocolitica, due to additional virulence factors encoded on two plasmids

Answer 10

Yersinia pestis

Question 11

Plasmid 1

Answer 11

antiphagocytic capsule (fraction 1) and phospholipase D

Question 12

plasmid 2

Answer 12

plasminogen activator

Question 13

aids systemic spread

Answer 13

plasminogen factor

Question 14

also contributes to the pathogenesis of disease

Answer 14

endotoxin

Question 15

causative agent of Enteric Yersiniosis

Answer 15

Y. pseudotuberculosis

Question 16

caused by Y. pseudotuberculosis

Answer 16

Enteric Yersiniosis

Question 17

has been reported in sheep, goats, and cattle under 1 year of age characterized by profuse watery diarrhoea, sometimes blood stained which may rapidly fatal if untreated

Answer 17

Enteric disease

Question 18

the disease may be precipitated in the winter months by stress factors such poor nutrition, weaning, transportation and cold wet conditions

Answer 18

Enteric Yersiniosis (enteric disease)

Question 19

caused by Y. pseudotuberculosis, occurs in birds kept in cages or aviaries. Infected birds may die suddenly. Some may display ruffling of feathers and listlessness shortly before death

Answer 19

Septicaemic Yersiniosis

Question 20

infection with Y. pseudotuberculosis in colonies of guinea pigs or rodents is usually introduced through faecal contamination of food by wild rodents

Answer 20

Pseudotuberculosis in laboratory animals

Question 21

infection with Y. pestis by ingestion of infected rodents

Answer 21

Feline plaque

Question 22

most common form of the disease characterized by enlarged lymph nodes (buboes) associated with lymphatic drainage from the site of infection

Answer 22

Bubonic

Question 23

clinical signs include fever, depression, and anorexia. Affected superficial lymph nodes may rupture, discharging serosanguineous fluid or pus

Answer 23

Bubonic

Question 24

may occur without lymphadenopathy and is potentially fatal

Answer 24

septicaemic

Question 25

may results from haematogenous spread. potentially source of human infection through aerosol generation, they should be euthanized

Answer 25

Pneumonic Lesion