Re: How does botulism kill people?

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!