Genus Clostridiun. C.botulinum

Question 1

Classification

Answer 1

Family: Bacillaceae
Genus: Clostridium
Species: botulinum

Normal habitat: soil

Organism and botulinum toxin transmitted in improperly preserved (canned) food.

Question 2

Morphology

Answer 2

Gram positive rods

Spore forming (subterminal endospores)

Motile (peritrichous flagella)

Question 3

Growth characteristics

Answer 3

Anaerobic

Fastidious

Question 4

Antigenic structure

Answer 4

Somatic O antigens

H flagella antigens

Question 5

Virulence factor

Answer 5

Spores

Botulinum toxin:

• neurotoxin
• relatively heat-labile and resistant to protease
• types A - G
• the most potent toxic material known

7 types: A to G (based on the serologic tests of the neurotoxin)

A, B, E and F = cause botulism in Man

C and D = cause botulism in animals and birds

G = pathogenicity unknown

Question 6

Disease

Answer 6

Classic botulism = food poisoning

• ingestion of food with bacteria already producing toxins
• descending paralysis = flaccid paralysis

Infant botulism —> most common form
- Flaccid paralysis = “floppy baby syndrome”
- The way of infection is different from adults:
Transmitted through ingestion of honey that contains spores

Question 7

Microbiological diagnosis

Answer 7

• presence of toxin in patient’s serum or stool or in food.
  > detection of toxin involves either antitoxin in serologic tests or production of the disease in mice
• serologic tests for antibody in the patient are not useful

Question 8

Treatment and prevention

Answer 8

• antitoxin to type A, B and E are made in horses
• respiratory support may be required

Prevention:

Public health measures:

• observing proper food preservation techniques
• cooking all home-canned food
• discarding bulging cans