Tetanus is a serious illness caused by tetanus bacteria. The bacteria live in soil, saliva, dust and manure. The bacteria usually enter the body through a deep cut, like those you might get from cutting yourself with a knife or stepping on a nail.

The infection causes painful tightening of the muscles, usually all over the body. It can lead to "locking" of the jaw, which makes it impossible to open your mouth or swallow. If this happens, you could die of suffocation.

If you get tetanus, there is usually a long course of treatment. The tetanus vaccine can prevent tetanus but its protection does not last forever. Adults should get a tetanus shot, or booster, every 10 years. If you get a bad cut or burn, see your doctor--you may need a booster.