(VII)Gram Positive Rods Aerobic (1) Bacillus spp.

Question 1

2 example of Bacillus species: […]

Answer 1

2 example of Bacillus species:
B. cereus and B.anthracis

Question 2

Characterize (4) : Bacillus spp.

Answer 2

(1) Gram (+) rods in chains
(2) Protein capsule
(3) Obligate aerobe
(4) Spores

(Sometimes described as boxcar shaped)

Question 3

Anthrax is diagnosed through […]

Treatment of Anthrax is with […]

Answer 3

Anthrax is diagnosed through** culture** (vesicle fluid, blood, sputum)

Treatment of Anthrax is with ciprofloxacin (fluoroquinolone + doxycycline) /penicillin

Treat anthrax w flowers~

Question 4

Bacillus anthracis infection

Transmission:
[…]

Clinical Presentation
[…]

Answer 4

Bacillus anthracis infection

Transmission:
Zoonosis ( large amounts of resistant spores – can live up to years – released when infected animal dies, also carried on animal products like bone meal & hide)

Clinical Presentation
Anthrax
- Cutaneous anthrax: black eschar, vesicles, oedema
- Respiratory anthrax: severe hemorrhagic infection and pneumonia
- Intestinal anthrax: hemorrhagic diarrhea

• All forms of anthrax can lead to septicaemia & death

***Note: used in biological warfare

“Eschars is a slough or piece of dead tissue that is cast off from the surface of the skin particularly after a burn injury, but also seen in gangrene, ulcer, fungal infections, necrotizing spider bite wounds, tick bites associated with spotted fevers, and exposure to cutaneous anthrax”

Question 5

Bacillus cereus infection:

Transmission: […]

Clinical Presentation
[…]

Answer 5

Bacillus cereus infection:

Transmission: Food poisoning (classically fried rice, preformed toxin heat stable)

Clinical Presentation
Food poisoning (2 syndromes)
- rapid onset (within 6 hours) - vomitting
- slower onset (8-24h): diarrhea and abdominal pain

Question 6

What are the virulence factors of B. anthracis?

• […]
• […]

Answer 6

What are the virulence factors of B. anthracis?

• Protein capsule (resistance to phagocytosis and complement system)
• Tripartite toxin (Protective antigen + Oedema/Lethal factor)

Oedema toxin = Protective antigen + Oedema factor
Lethal toxin = Protective antigen + Lethal factor

Question 7

What is the histology of B. anthracis? What is the special stain used?

[…]

Answer 7

What is the histology of B. anthracis? What is the special stain used?

Large GPRs with pink-stained capsule using McFadyean’s stain

Spores often visible within bacterium

McFadyean’s stain is known to take too damn long to make