Staphyloccocus & Streptococcus Flashcards

(46 cards)

1
Q

Staphylococcus commensals

A
  1. Transient contaminants
  2. Short-term residents
  3. Long term colonizers
  4. Skin and mucous membranes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Staphylococcus affects

A

both animals and man

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

S. aureus causes

A

Wound infections in animals and serious diseases:

  • Pneumonia
  • Ostemomyelitis
  • Mastitis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

S. hyicus causes

A

Epidermitis in pigs: GREASY PIG DISEASE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Features of Staphylococcus

A
  • Gram + cocci
  • Clusters: “staphyle” (bunch of grapes)
  • Facultative anaerobes
  • Catalase +
  • Fermentative
  • resistant to lysozome
  • plasmids
  • bacteriophage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Are the following coagulase + or -?
S. aureus
S. pseudintermedius
S. hyicus

A

Coagulase positive:

- Coagulase produced by the bacteria activates thrombin in plasma which causes clumping of fibrin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Are the following coagulase + or -?
S. epidermidis
S. hyicus (some)

A

Coagulase - (no clumping)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Types of Adhesins in Staphyloccocus

A
  • Adhesins with MSCRAMMS

- main adhesins: Fibronectin, collagen, elastin, coagulase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

MSCRAMMs stands for

A

Microbial Surface Components Recognising Adhesins Matrix Molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Parasitic properties of staphylococcus

A
  1. Adhesins
  2. Capsule
  3. Cell wall constituents
  4. tolerate high salt and fatty acids
  5. Exotoxins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Staphylococcus capsule

A

Is antiphagocytic with 12 immunotypes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Cell wall consituents of Staphylococcocus

A

Protein A binds Fc fragment of Ig and therefore is antiphagocytic. This limits optimisation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Exotoxins of staphylococcus

A
  • alpha toxins enable destruction of phagocytes

- Toxic shock syndrome toxin (TSST)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Staphylococcus enters via

A
  1. Hair follicles
  2. Skin glands
  3. Wounds
  4. Compromised skin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Staphylococcus: Host factors

A
  • endogenous or exogenous
  • phagocytosis is main defence: immunosuppression predisposes to disease
  • pus results from invasion of compromised epithelium or mucous membranes
  • systemic disease occurs if enters blood stream
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Staphylococcus: Environmental factors

A

Spreads through shedding of epithelium:

  1. Equipment (milking machines: mastitis)
  2. Bedding/housing (perch Bumblefoot)
  3. Contact (zoonotic)
  4. Predisposing factors (Abrasions, arthropods)

Hygiene is important

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How S. aureus causes mastitis

A
  1. Lives inside or outside udder on teat skin
  2. grows well in milk
  3. lives high up in glands and is contagious - milking machines
  4. Penetrates interstitial tissue and survives intracellularly
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Treatment for S. aureus mastitis

A
  • eliminate pathogen or animal

- Dry cow therapy for subclinical disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How bovine mastitis occurs

A
  1. Structural defense of teat
  2. White blood cells destroy bacteria
  3. Atrophy (loss) of alveoli
20
Q

Porcine Exudative Dermatitis aka

A

Greasy pig disease

21
Q

Greasy Skin disease caused by

22
Q

S. hyicus

A
  • S. hyicus enters through minor abrasions and bites
  • highly contagious
  • Not itchy
  • Coagulative +
  • Exfoliative toxin
  • non-haemolytic
23
Q

Control of staphylococcal disease

A
  1. Hygiene
  2. Maintain skin health
    - Nutrition
    - grooming
    - ectoparasite prevention
  3. Minimise likelihood of abrasions/spread
    - consider perching management (carpet)
    - rough bedding
    - milk machine maintenance
    - stress and co-mingling
    - Dry cow therapy
    - Isolate infected pigs
24
Q

Streptococcus Features

A
  • Gram + cocci
  • chains
  • Facultative anaerobes
  • Catalase -
  • Primary pathogens or secondary invaders
  • Haemolysins: Streptolysins O and S (kills phagocytes)
25
Morphology of Streptococcus
- long chains: S. agalactiae and S. equi | - Short chains: S. uberis (powdery deposit)
26
Which streptococcal pathogens cause bovine mastitis?
S. afalactiae S. dysgalactiae S. uberis
27
Which streptococcal pathogens cause strangles?
S. equi subsp. equi
28
Which streptococcal pathogens cause Pharyngitis "strep throat" in humans?
S. pyogenes
29
Which streptococcal pathogens cause pneomococcal pneuomonia in humans?
S. pneumoniae
30
8 Parasitic properties of Streptococcus
1. Adhesins 2. Capsulated 3. M protein 4. Cytotoxins 5. Spreading Factors 6. Superantigens 7. Extracellular 8. Multifactorial
31
Streptococcus: Adhesins
MSCRAMMS | Lipoteichoic acid
32
Streptococcus: capsulated
Hyaluronic acid | Polysaccharide
33
Streptococcus: M proteins
are antiphagocytic and adhesin
34
Streptococcus host factors
- Commensal or obligate parasites: Host compromise - Exogenous/endogenous: some are contagious - Opsonising antibody
35
Environmental factors
- fragile - mastitis: milking equipment, hygiene, teat handling - transport pneumonia: horses travel long distance in shuttle stages- unable to move head freely
36
S. agalactiae
- obligate parasite of bovine mammary gland - causes contagious mastitis - sensitive to penicillin
37
S. dysgalactiae
- causes bovine mastitis - opportunistic pathogen - "environmental" organism - DOES NOT PERSIST IN UDDER - NON CONTAGIOUS - causes acute mastitis
38
S. uberis
- opportunistic pathogen - causes acute mastitis - non-contagious - hygiene before and after milking
39
Streptococcal bovine mastitis: Control and prevention
1. Dry cow therapy 2. Avoid teat lesions 3. Clean and dry teats before milking 4. Milking machine & parlour hygiene 5. Antimicrobial usage
40
Strangles is caused by what pathogen?
S. equi subsp equi
41
Strangles
- highly contagious - obligate parasite of nasopharynx - purulent inflammation
42
"Bastard" strangles
Abscessation of lung or in abdomen
43
Cytotozins and M proteins are important for
resisting phagocytosis
44
S. equi subsp equi can be differentiated from biochemistry
Lactose - Sorbitol - Trehalos -
45
S. equi subsp equi strangles epidemiology
- oral or nasal route - direct or indirect contact - recovered animals may be carriers - recovered mares produce antibody protection to foals - persists in environment
46
Strangles control and prevention
- vaccine; M protein and local response important - quarantine - antimicrobials: penicillin