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Flashcards in Bacillus Deck (48):
1

What is Bacillus also known as?

Anthrax

2

True/False: Bacillus forms a spore

True!!!!- They are spore forming 

3

What is the main pathogen of Bacillus?

Bacillus Anthracis 

4

What does Bacillus form?

Very long gram positive rods 

A image thumb
5

Are Bacillus anaerobic or aerobic?

Facultative anaerobes 

6

Bacillus is catalase _____ and oxidase ______

catalase positive and oxidase negative 

7

How do you distinguish Bacillus from Clostridia?

Catalse test

If it bubbles you have Bacillus

If it doesn't bubble you have clostridia 

8

Where is Bacillus typically found?

soil and water

9

Why can Bacillus survive in the environement for long periods of time?

endospore is very hearty- can live forever 

10

What plasmids does Bacillus produce?

pX01 and pX02

plasmids makes them very virulent

PX02 encodes for the capsule 

11

What regulatory proteins does Bacillus have?

AtxA- anthrax toxin activator

AcpA- Anthrax capsule activator 

12

What does the capsule do in Bacillus

inhibits phagocytosis

composed of D-Glutamyl polypeptide

 

13

non encapsulted isolates are essentially _____

avirulent

vaccine can get a good reaction against an avirulent bacillus anthracis

14

What is the two toxins of Bacillus?

Lethal toxin and Edema toxin 

15

What is Lethal toxin composed of?

Protective antigen (PA) and lethal factor (LF)

LF is responsible for the toxic activity 

Protective antigen is for adhesion 

16

What does Lethal toxin cause at high and low doses?

At low doses causes cytokine storm- multi organ failure and death

At high doses- apoptosis of macrophages 

17

What is the lethal toxin and edema toxin under the control of?

AtxA 

18

what is the edema toxin composed of?

protective antigen and edema factor

19

What does edema factor cause?

electrolyte and fluid loss in affected cells 

20

Why do we incinerate carcasses that have bacillus anthracis?

because the vegetative cells can survive for 2 weeks in unopened carcass

21

what kind of soils does bacillus anthracis love?

calcium rich soils 

calcium plays a huge rold in formation of the endospore 

22

Spores can persist for ____ in dry environment

decades 

23

Does Bacillus anthracis have a large variability?

No- they have spores that live forever on the ground so they don't need to be variable 

24

What species are resistant to Bacillus?

Carnivores are fairly resistant

Birds are totally resistant 

25

What is the infectious unit of the Bacteria?

Endospore 

26

What are the modes of transmission of Bacillus?

ingestion of contaminated feed and water- bone meal and animal feed supplements are common vehicles 

wound infection 

arthropod bites 

Sheering sheep- wool may have anthrax 

27

Pathogenesis of Bacillus 

1. animal ingests the spore or it enters a wound

2. Bacteria phagocytosed by macrophages- spores germinate into vegetative form

3. due to environmental cues the toxins will start getting released

4. Bacteria escapes its vegetative form from the phagolysosome and causes cytokine storm

5. fluid and elecrolyte loss via edema factor

6. multi organ dysfunction, shock, and depletion of clotting factor 

28

when does the vegetative form start?

Once the spore gets into the tissue 

29

What causes bleeding at body orifices?

Lethal factor 

This is followed by shock and death 

30

What are some post mortem findings with Bacillus?

ABSENCE OF RIGOR MORTIS

non clotting blood- bleeding from the nose and other orfices 

hemorrhage

friable spleen 

A image thumb
31

Who are the most susceptible species for Bacillus?

Sheep and Cattle 

They get Septicemia!!!

32

True/ False: Bacillus has a long incubation period?

False- very short incubation period 1-5 days 

sometimes animals can die without clinical signs 

33

What are clinical signs in horses with Bacillus?

Colic, diarrhea, and edema 

34

What clinical signs are produced in swine with Bacillus?

obstructive edema may cause death 

hemorrhagic enteritis 

35

Pathogenesis of Cutaneous Anthrax 

Q image thumb

1. bacteria enters through cut or abrasion

2. incubation for a few days- papule forms

3. papule becomes blister that ulcerates

4. lesion dries and leaves necrotic area called BLACK ESCHAR

low fatality 

36

What causes gastrointestinal anthrax and what is the outcome?

consumption of contaminated meat 

Septiemia can occur

Comes with a high fatality rate! (25-60%)

37

What are the characteristic of inhalation anthrax?

Mortality is 100% 

pulmonary edema and hemorrhagic pneumonia

meningitis and hemorrhage in the brain 

sometimes incubation can be really low even with high doses

 

38

Does Bacillus typically infect from animal to animal?

No- not unless you have a lot of infected carcasses around

39

What kind of sera can help alleviate disease?

Hyper immune sera

40

What kind of vaccine can be used that lacks the pX02 plasmid?

Sterne strain vaccine 

41

True/False: Field necrospsys should be performed on carcasses

False: NO FIELD NECROPSY- you will expose yourself and the environment 

42

What stain is used to detect Bacillus?

McFadyeans methylene blue - you can see the capsule 

43

Picture of Bacillus anthracis to know

A image thumb
44

Bacillus is a facultative anaerobe, when it is aerobic and doesn't form a capsule what appreance does it have on growth media?

medusa head 

A image thumb
45

What test is characterized by blebbing?

String of Pearl test 

46

What thermopreciptation test is very specific for bacillus anthracis? 

Ascoli Test 

47

What is the treatment for Bacillus?

antimicrobial treatment with antiserum - Penicillin G 

animals are isolated and treated- quarantined for 3 weeks

48

Bacillu causes a _____ disease

Reportable 

incinerate the carcass