Exam 2: Streptococcus

Question 1

What is the result of streptococcus in a gram stain? Catalase test?

Answer 1

Positive

Negative

Question 2

What does most streptococcus require to grow?

Answer 2

Blood or serum

Question 3

When does streptococcus not grow?

Answer 3

When shed into the environment

Question 4

What is used when streptococcus is classified by the Lancefield’s serological groups?

Answer 4

Cell wall antigens

Serological agglutination

Question 5

What does antigenic specificity, used in Lancefield’s serological groups, reside in?

Answer 5

Polysaccharides attached to teichoic acid layer of cell wall, so called “C” substance (for carbohydrate)

Question 6

What are the virulence factors for streptococcus?

Answer 6

Capsules: hyaluronic acid is non-immunogenic and non-antigenic, act as an adhesin and are antiphagocytic
M proteins, lipoteichoic acid, and other cell wall proteins with fimbriae cause adherence and are antiphagocitic

Question 7

What group species is S. pyogenes?

Answer 7

Only group A species

Question 8

What kind of pathogen is S. pyogenes?

Answer 8

Mostly human

Question 9

What is the major virulence factor of S. pyogenes?

Answer 9

Over 60 different M proteins

Question 10

Why are there no vaccines available for S. pyogenes?

Answer 10

Immunity is type-specific and there are so many M proteins that it is difficult to develop a vaccine

Question 11

What group species is S. agalactiae?

Answer 11

Only group B species

Question 12

What is used in late pregnancy?

Answer 12

Group B strep test

Question 13

What species is related to CAMP factor?

Answer 13

S. agalactiae

Question 14

What does CAMP factor cause?

Answer 14

Complete lysis of cow or sheep RBC in the presence of S. aureus beta hemolysin producing arrowhead appearance of enhanced hemolysis

Question 15

What kind of pathogen is S. agalactiae?

Answer 15

Obligatory intramammary

Question 16

Where does S. agalactiae live as an obligatory intramammary pathogen?

Answer 16

Milk duct

Question 17

What is S. agalactiae a common cause of?

Answer 17

Contagious bovine mastitis

Question 18

How is S. agalactiae spread?

Answer 18

Could not live outside of host, but easily spread by milking equipment or suckling calves

Question 19

What is S. agalactiae sensitive to?

Answer 19

Penicillin

Question 20

Where is S. dysgalactiae considered to be normal flora?

Answer 20

Mouth, vagina, and skin other than udder

Question 21

Where does S. dysgalactiae survive well?

Answer 21

In environment

Question 22

Can S. dysgalactiae be totally eliminated?

Answer 22

No

Question 23

What is the most common cause of mastitis?

Answer 23

S. dysgalactiae

Question 24

What is S. zooepidermicus subsp. zooepidermicus common normal flora in?

Answer 24

Many animals

Skin and upper respiratory track of horse

Question 25

What is S. zooepidermicus subsp. equi the etiological agent of?

Answer 25

Strangels, a regional or generalized suppurative lymphadenitis

Question 26

How is S. zooepidemicus subsp. equi differentiated from S. zooepidermicus subsp. zooepidermicus with morphology and biochemically?

Answer 26

Morphology: large mucoid colonies may run together, wide zone of clear hemolysis Biochemically: S. equi does not ferment lactose or sorbitol

Question 27

What are the virulence factors for S. zooepidermicus subsp. zooepidermicus?

Answer 27

M protein and capsule

Question 28

What is a source of streptococcus?

Answer 28

Aerosol transmission

Question 29

What is the exposure of streptococcus?

Answer 29

Inhalation, ingestion, contact, insects

Question 30

What diseases can occur with or because of streptococcus?

Answer 30

Bastard strangles Gutteral pouch empyema Purpura hemorrhagica

Question 31

What kind of immunity is there for streptococcus?

Answer 31

Mainly humoral

Question 32

Is a vaccine available for strangles?

Answer 32

Yes

Question 33

What is the treatment for something caused by streptococcus?

Answer 33

Drain abscess Antimicrobial therapy (controversial) Procaine penicillin G is the antibiotic of choice

Question 34

Describe S. pneumoniae

Answer 34

Primates and humans only | No specific "C" substance or "M" protein

Question 35

What does S. iniae occur in?

Answer 35

Many species of fish as a systemic disease

Question 36

Where is S. mutans found?

Answer 36

Plaque and dental caries in humans