- Clostridium botulinum is a large, Gram-positive endospore-forming rod
- Like all Clostridia, C. botulinum is a strict anaerobe
- Able to use a wide variety of sugars and other biological material as carbon and energy sources
- Cannot grow in pHs of 4.5 or lower
- Widely distributed in the environment, usually soil, lake sediment, and decaying vegetation
- Food can be contaminated with endospores. When preserved through canning or otherwise stored anaerobically, the endospores germinate and produce exotoxin.
- Endospores are often found in raw honey. When ingested by infants who do not have established natural flora, this can lead to gastrointestinal infection.
- Naturally occurs infrequently and sporadically
- Most cases are intoxication through contaminated food rather than infection
- Infection can occur in infants through ingestion of endospores
- Toxin inhibits acetylcholine release leading to flaccid paralysis (cannot contract muscles).
- Early symptoms appear within about a day and include weakness, dizziness and dryness of the mouth. Other gastrointestinal symptoms may be present.
- In later disease, it becomes difficult to speak and swallow, muscle weakness increases, and eventually the diaphragm can be paralyzed
- Primary treatment is antitoxin and supportive therapy
- Without treatment, mortality rate is >60%, but with treatment it is ~4-20%
Primary Virulence Factors
- The only virulence factor is botulinum toxin (link to info in textbook)
Additional information: http://textbookofbacteriology.net/clostridia_4.html