Why do I need the Tetanus shot when I step on a nail?
By Grant Huttar
Clostridium tetani is the gram-positive bacillus bacterium that can cause the condition of tetanus or lockjaw. Commonly associated with rusty nails and the like, C. tetani is more often found in dirt and manure. Stepping on a nail or getting jabbed by a thorn typically results in a puncture wound. Puncture wounds are deep and narrow causing the deepest portions to have limited contact with oxygen. C. tetani is an anaerobic bacterium (which thrives in low oxygen environments) which means the pocket in a wound is a perfect niche for growth of this type of bacteria. Symptoms can include a stiff neck or jaw, muscle spasms, and difficulty swallowing. The onset of symptoms can occur within 48 hours or take up to two weeks to manifest, cases that develop symptoms more rapidly usually result with more severe cases. C. tetani affects the nervous and muscular system by the release of a toxin known as tetanospasmin, this results in a type of paralysis known as spastic paralysis. Spastic paralysis is the opposite of what most associate with paralysis, instead of the muscles staying flaccid they remain in a permanent contraction, this can lead to fatal effects if it controls the diaphragm. The vaccine is a toxoid meaning it protects against the toxin that C. tetani produce to mitigate its effect. Typically, the vaccine is a modified version of tetanospasmin that has been inactivated, the body will be able to generate antibodies against this toxin. This active immunity will generally grant immunity for around ten years after the initial set of injections that are administered to children.