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Basic Facts About Tetanus

The tetanus bacterium clostridium tetani, a cousin of the botulism organism, produces a toxin 50 times as poisonous as cobra venom and 150 times stronger than strychnine.  A wound no larger than a pin prick can harbor enough bacteria to produce sufficient toxin to kill an unvaccinated human.  An amount of purified tetanus toxin weighing no more than the ink in the period at the end of this sentence would be enough to kill 30 grown men.  It is one of the most deadly poisons known to man.  A natural habitat of this bacterium is soil. 

The cause of tetanus is not the bacterium itself, but the toxin which it produces.  Since it is an anaerobe (meaning that it can thrive only in locations where there is no oxygen) it causes trouble when introduced into a wound where it is cut off from an air supply.  That's why puncture wounds are a potential problem.  Their very nature is to close up and keep out the air.  However, even a superficial scratch is susceptible to the infection.  The bacteria usually begin to multiply right away after finding the airless environment, but the spores can remain dormant, resulting in infection many years later.  Whenever infection develops, the prognosis is grim.

Anti-tetanus shots should be viewed as a necessity for those who may have skin breaks and are likely to be in contact with soil.  For the non-immunized person simply trying to grow roses, a relatively minor-seeming puncture as from a thorn, if done in the presence of bacterial contamination on the thorn (from soil) can result in serious consequences. 

A simple immunization once every 5-10 years is all that's recommended.  Your doctor can advise the best frequency for you, depending on your gardening activity.


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Updated November 08, 2004
Copyright 2004 ARS Pacific Northwest District