Tetanus is an infection which causes muscle spasms. As most often these spasms begin in one's jaw, later progressing to the rest of the body, the infection is also called lockjaw.

The disease usually lasts from 2 weeks to a month. Its main manifestations are spasms, which occur frequently and last several minutes. In some tough cases the bones can be broken. Other symptoms may include fever, sweating, headache, trouble swallowing, high blood pressure, and a fast heart rate. Symptom expression may take place right after the infection or up to twenty days later. The treatment usually continues several months and about 10% of the cases have a fatal outcome.

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