Bacillus

Question 1

How to classify?

Answer 1

Gram positive rod
Obligate aerobe
Spore forming

Question 1

How is Bacillus anthracis transmitted?

Answer 1

Extremely tough spores which infects many animals and last for decades in/on soil, animal hides (drums, building materials made with fur/hides), meat from diseased and dead animals

Question 2

Virulence factors of B.anthracis

Answer 2

1. Protein capsule - resistance to phagocytosis and complements
2. Tripartite toxin (Oedema toxin - protective antigen + oedema factor, lethal toxin - protective antigen + lethal factor)

Question 3

What diseases does B.anthracis cause?

Answer 3

1. Cutaneous anthrax - black eschar, vesicles, oedema
2. Respiratory anthrax - haemorrhagic pneumonia
3. Intestinal anthrax - haemorrhagic diarrhoea
4. Injected anthrax

All can lead to septicaemia and death

Question 4

How to diagnose B.anthracis?

Answer 4

Culture - vesicle fluid, blood, sputum

Question 5

Treatment for B.anthracis

Answer 5

Ciprofloxacin, penicillin

Question 6

What is the capsule made of?

Answer 6

Poly-D-glutamic acid

capsule issa protein!

Question 7

What can anthrax be used for? Why? How?

Answer 7

Bacteriological warfare!
- Easy and cheap to make
- Aerosol delivery -> pneumonia
- Multi-resistant strains may be used

Question 8

How is B.cereus transmitted?

Answer 8

Classically associated with fried rice with complicated mixture of pre-formed heat stable enterotoxin

Question 9

What are the two diseases B.cereus causes? What are the toxins involved?

Answer 9

1. Rapid onset (pre-formed toxin): vomiting
2. Slower onset (toxin formed in GIT): diarrhoea and abdominal pain

Causes wound infection in cornea too!

Question 10

What does Bacillus contaminate?

Answer 10

Blood culture