Zoonoses 1 - Bacillus, Brucella, Francisella Flashcards Preview

Bacteriology Lectures > Zoonoses 1 - Bacillus, Brucella, Francisella > Flashcards

Flashcards in Zoonoses 1 - Bacillus, Brucella, Francisella Deck (51):
1

Bacillus organism appearance

G+ rods

Chains, palisades, clumps

2

Bacillus metabolic features

  • Sporulation
  • Aerobic (some have butanediol or lactate fermentation)
  • Found in soil or on leaves

3

B. cereus causes ____

acute food poisoning

 

*NOT a zoonosis

4

B. cereus organism appearance (microscopic and on plate)

"Subterminal" spores

Large, flat, rough colonies on agar

5

Two varieties of B. cereus

  1. Emetic = like staph, acute onet, nausea + cramps. 12 hour recovery
  2. Diarrheal = slow onset, profuse diarrhea, no vomit.

6

B. cereus source

Cooked rice and pasta that has been cooled too slowly

 

*spores germinate and produce toxin

7

B. cereus toxins

emetic toxin

K+ ionophore

3 enterotoxins

Hemolytic

Non-hemolytic

Cytotoxin

8

Bacillus zoonotic organism

B. anthracis

9

B. anthracis organism appearance (microscopic and on plate)

Central spores

Cut glass appearance on blood agar

NO hemolysis

10

B. anthracis contains a _______ capsule.

 

What stains for this?

poly-D-glutamate

 

*M'Fadyean's stain

11

B. anthracis presents as _____--> _______

Then it becomes ______

It is able to _________

Papule ---> eschar

systemic (disseminates)

infect any organ 

12

B. anthracis spores are viable in ____ for ______

soil for >50 years

13

Human infection of B. anthracis comes from  _____ or ______

handling infected animal materials (spores coming in contact with mucous membranes)

OR

Enters through abrasions

14

Spore life cycle of B. anthracis

  1. Enter MQ
  2. Germinate within phagolysosome when exposed to Oxygen radicals

15

B. anthracis toxin

Tripartite AB-type toxin

16

Three parts of B. anthracis toxin

B part = Protective antigen = binds and facilitates entry

A parts:

Lethal Factor = MAPK protease (causes the necrosis)

Edema Factor = Calmodulin-dependent adenyl cyclase (makes cAMP, causes secretion of water into tissues)

17

B. anthracis toxin is carried on _____

The capsule is carried on ______

pX01

pX02

18

Both virulence factors of B. anthracis (toxin and capsid) are ______

Which one is necessary for full virulence?

plasma-encoded

need both for full virulence

19

B. anthracis antibiotics

Penicillin (Cutanteous)

Doxy

Ciprofloxacin

20

B. anthracis vaccines

Live = from pX02-cured strain

PA Toxoid vaccine for military

 

21

B. anthracis preventive measures for stockmen?

Livestock vaccination and protective clothing

22

Passive immunity for B. anthracis possible?

Yes, new trials of anthrax immunoglobulin

23

Brucella organism

gram negative aerobic coccobacillus

24

Brucella growth, motility, and metabolism/location

slow growth

nonmotile

Facultative intracellular parasite

25

Brucella lives inside

MQ and PMN

 

(associated with granulomas)

26

Brucella species

melitensis

abortus

suis

canis

27

Brucella incubation

1-6 weeks

(can be months)

28

Brucella clinical features (three main ones, then a few others)

  • undulant fever
  • granuloma
  • long term debility

 

(also general weakness, psychoneuroses, malaise)

29

Brucella causes ____ in cattle.

 

How does this happen?

abortions

 

  • bacteria bind to erythritol on testes or placenta
  • forms foci that detach microvilli

30

Brucella in ungulates

Bang's disease

31

Brucella transmited from male ungulates via

semen

32

Humans acquire Brucella via what three methods

infected milk

handling animals

lab accident!!!

33

Brucella Dx

blood sample and serology or culture

34

How does Brucella spread in body?

from portal of entry via lymphatics and bloodstream

35

Brucella does not form an...

endotoxin.

Disease is caused by an inflammatory response to bacterial growth

36

What causes undulant fever in Brucella

due to release from MQ and general host response to increased infectious titer

37

Brucella control (2)

  • pasturized milk
  • eradication from herds (immunization, segregation, testing and slaughtering of infected animals)

38

Brucella antibiotics

Doxy + Rifampin +/- streptomycin

 

***Limited effectiveness because of intracellular location

39

Brucella vaccine

NOT in US, because of LPS toxicity

Live vaccine in russia

40

Francisella organism, shape, growth and metabolism

  • gram negative coccobacillus
  • Pleomorphic
  • slow growth
  • fastidious requirements (Cysteine)

41

Francisella incubation

2-6 days

42

Francisella primary presentation (4 Sx)

  • inflamed ulcerated papule at infection site
  • Fever
  • Toxemia
  • Abcess (liver, spleen, lungs, lymph nodes)

43

Francisella reservoirs

Type A = Rabbits

Type B = Beaver + Rodents

 

*type A is more severe..."Rabbit fever"

44

Francisella human transmission (4)

  • Skinning infected animals 
  • Aerosol inhalation from carcass
  • Ticks/Deerflies
  • Laboratory hazards

45

Francisella infectious dose?

10 bacteria!

46

Other Francisella Epidemiological facts

  • Weaponized in WW2
  • Need P3 comtainment lab to grow it

47

Francisella pathogenic factors (4)

capsule that resists complement

coiling phagocytosis into MQ

PAI

LPS

48

Coiling phagocytosis into MQ prevents

oxidative burst

49

Francisella grows in ___ and ___

MQ and PMN

*grows to high titer even in epithelial cells

50

What is a PAI (Francisella)?

What does it contain?

pathogenicity island

contains: 17 genes, T4SS + effectors (MQ survival)

51

Francisella control, antibiotics and vaccine

  • isolation of lab organisms + careful skinning
  • Doxy, cipro, gentamycin
  • Live cell vaccine for military