Tetanus is an infection of the nervous system caused by the Clostridium tetani bacteria.

What is going on in the body?

The bacteria that cause tetanus live in the soil. They are also found in animal intestines and human feces. Tetanus occurs when wounds or an infant's umbilical cord are contaminated with the bacteria. The bacteria then multiply and produce a toxin, which affects the nervous system. The toxin travels through the nerves to the brain and spinal cord.

What are the causes and risks of the infection?

Tetanus is caused by a toxin made by the bacteria Clostridium tetani. The bacteria are generally introduced into the body through wounds in the skin. The risk of tetanus increases with deep puncture wounds infected by dirt or feces. The bacteria can also be introduced through the umbilical cord of a newborn.

Common sources of tetanus infection include the following: