Yersinia

Question 1

Identify the bacteria

● pleomorphic (coccoid to bacilli)
● 5um long or more
● single; occasionally in chains
● sometimes bipolar stained

Answer 1

Yersinia

Question 2

Yersinia

● gram positive or gram negative?
● acid fast or non-acid fast?
● capsulated or non-capsulated?

Answer 2

● gram negative
● non-acid fast
● non-capsulated

Question 3

French bacteriologist who isolated Y. pestis

Answer 3

Yersin

Question 4

Yersinia has what type of flagella when cultured at 18-30ºC?

Answer 4

Peritrichous flagella

Question 5

Yersinia has what type of flagella when cultured at 37ºC?

Answer 5

None

flagella is detached and antigens are absent at 37º

Question 6

Yersinia colonies on culture are hemolytic or non-hemolytic?

Answer 6

non-hemolytic

Question 7

Colony size of Yersinia on culture?

Answer 7

0.1-1.0mm

Question 8

Colony appearance of Yersinia on culture? (3)

Answer 8

● translucent and granular
● centers of old colonies are more opaque
● periphery colonies have radial striations

Question 9

Colony elevation of Yersinia on culture?

Answer 9

centers of old colonies are raised

Question 10

Optimum growth temperature of Yersinia?

Answer 10

28ºC

Question 11

Yersinia can ferment what?

Answer 11

glucose and other carbohydrates

Question 12

Gas production of Yersinia?

Answer 12

Negative

little to no gas

Question 13

Does Yersinia produce urease?

Answer 13

No

can’t break down urea

Question 14

cause of plague in 1894

Answer 14

Yersinia pestis

Question 15

Cause of plague-like disease in guinea pigs, sometimes in rats, occasionally in other rodents, rare in other animals

Answer 15

Yersinia pseudotuberculosis

Question 16

Envelope antigen, composed of protein and carbohydrates, important virulence factor, found in Y. pestis

Answer 16

F1 antigen

Question 17

Plasmid-encoded antigens that contribute to virulence and immune modulation, found in Y. pestis and Y. pseudotuberculosis

Answer 17

V and W antigens

Question 18

Yersinia species are divided into 6 serogroups (I-VI), based on what?

Answer 18

● thermostable O antigens (O antigens l-VI)
● H antigens (a to e)

Question 19

Used to categorize bacteria into serogroups I-VI based on outer membrane polysaccharides

Answer 19

thermostable O antigens

Question 20

Flagellar antigens involved in motility and used in serotyping, identified by types a to e

Answer 20

H antigens

Question 21

Epizootiology and Pathogenesis of Yersinia in rodents, birds, and soil

Answer 21

infected by ingestion mostly during cold weather

Question 22

Yersinia infections in cattle are associated
with _________ and ________.

Answer 22

pneumonia and abortion

Question 23

Yersinia infections in cats are associated with…?

Answer 23

abdominal and urinary disturbances

Question 24

Yersinia infections in captive birds are associated with…?

Answer 24

Pseudotuberculosis

Question 25

These clinical signs of Yersinia infection can be observed in what animal? ● weight loss, develop diarrhea, and die in 3-4 weeks ● mesenteric lymph nodes greatly swollen and caseous, nodular abscesses in Peyer's patches, liver, and spleen

Answer 25

Guinea pigs

Question 26

Antigens necessary for virulence of Yersinia

Answer 26

F1, V, and W

Question 27

Incubation of Yersinia at __ºC results in loss plasmid encoded V and W antigens and loss of invasive ability

Answer 27

37ºC

Question 28

Immunity against Yersinia

Answer 28

intranasal (IN) administration of live, avirulent culture in guinea pigs against virulent strains

Question 29

Yersinia is a facultative intracellular parasite, meaning it can live inside host cells or outside them. Its ability to survive within cells contributes to its virulence and makes it challenging for immune system to clear infection. True or False?

Answer 29

True

Question 30

Immunity response crucial for controlling Yersinia infection, it involves T cells and macrophages that target and kill infected cells, especially in the case of an intracellular pathogen like Yersinia

Answer 30

Cell-mediated immunity

Question 31

How to diagnose Yersinia or differentiate Y. pestis?

Answer 31

● urease test ● ability to grow well in deoxycholate-citrate agar

Question 32

Yersinia is susceptible to which antibiotics?

Answer 32

1.) Chloramphenicol 2.) Nalidixic acid 3.) Streptomycin 4.) Sulfonamides 5.) Tetracycline

Question 33

Characteristics of Yersinia infection in humans

Answer 33

rare but severe fatal infection, mesenteric adenitis or septicemia

Question 34

Yersinia sp. present in alimentary tract of animals (as carrier) and can serve as source of infection for humans; ubiquitous but isolated from humans & chinchillas with alimentary tract disturbances

Answer 34

Yersinia enterocolitica

Question 35

Yersinia enterocolitica has also been isolated from...? (5)

Answer 35

1.) healthy cattle 2.) healthy swine 3.) meat 4.) shellfish 5.) ice cream

Question 36

Y. enterocolitica resembles which Yersinia sp. in colonial and microscopic morphology?

Answer 36

Y. pseudotuberculosis

Question 37

Y. enterocolitica is a heat-stable enterotoxin produced at 30ºC. True or False?

Answer 37

True

Question 38

Y. enterocolitica diseases in humans (4) ST MD

Answer 38

1.) symptoms that simulate appendicitis 2.) terminal ileitis 3.) mesenteric adenitis 4.) diarrhea

Question 39

Sources of Y. enterocolitica infections in humans (2)

Answer 39

animal sources contaminated food by human carriers

Question 40

Cause of bubonic plague or black death in humans, primarily disease of rats, but dogs and cats maybe naturally infected

Answer 40

Yersinia pestis

Question 41

In what climate does disease from Y. pestis infection assumes bubonic form?

Answer 41

Warm climate

Question 42

What are the swollen lymph nodes in bubonic form of disease from Y. pestis infection called?

Answer 42

Buboes

Question 43

In what climate does disease from Y. pestis infection is in pneumonic form?

Answer 43

Cold climate

Question 44

In which aspects does Y. pestis resembles Y. pseudotuberculosis? (3) CAM

Answer 44

● colonial morphology ● antigenic make-up ● microscopic morphology

Question 45

Bubonic plague is a disease of domestic animals. True or False?

Answer 45

False

Question 46

Rats can get infected by Y. pestis through what?

Answer 46

through bite of infected Rat Fleas (Xenopsylla cheopis)

Question 47

Where does Y. pestis multiplies?

Answer 47

in flea

Question 48

How fast does Y. pestis infection spread once introduced into population?

Answer 48

spreads rapidly

Question 49

In what form does the plague take in when it spreads in areas sparsely inhabited by humans?

Answer 49

Sylvatic form