|MadSci Network: Microbiology|
Good question! Botulism kills people by intoxication. More specifically, botulism results from the production of a toxin, botulinal toxin (Bot toxin for short) by an anaerobic (does not require oxygen for growth) bacterium, Clostridium botulinum. So why does Bot toxin kill people? It is a *very* powerful neurotoxin (meaning it affects the nervous system). Specifically, Bot toxin inhibits neurotransmitter release at the neuromuscular junction. Since no "message" can be sent, your muscles don't work. This results in a state of "flaccid paralysis". Initial neurologic symptoms include visual disturbance (blurred vision, pupils remaining dialated) and and dry mouth. Later stages include impariment of respiratory function and motor skills. In most cases, death will result form respiratory failure. Being an anaerobe, C. botulinum can grow in canned foods where there is no oxygen. In addition to canned foods, there also have been reports of botulism in young infants from ingesting honey. How does this happen? C. botulinum can form spores when the organism is put under stressed conditions (extreme temperature, pH, etc.). Spores are a survival mechanism for C. botulinum as well as other bacteria. When enough nutrients are around for growth, the spores can then "outgrow" from a spore to a new bacteria! Hope this answered your quesiton!
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