A toxin mediated disease caused by the bacterium, Clostridium tetani. These bacteria live mostly in dirt and gain entry into the body through skin wounds. They produce a bacterial toxin that attacks nerves, causing persistent contraction or spasms of the muscles. These painful muscle spasms cause "locking" of the jaw as well as problems with moving, breathing, eating, and drinking.
Tetanus is a very serious disease and can be fatal even when treated. Tetanus is still seen in children that have not been vaccinated and among some newborns whose mothers lack immunity to tetanus toxin. Tetanus also occurs in people in their 50s and 60s whose immunity has worn off.