An infectious disease, also known as lockjaw, which is caused by the toxin of Clostridium tetani. The bacterium may be isolated from fertile soil and the intestinal tract or fecal material of humans and other animals. Infection commonly follows dirt contamination of deep wounds or other injured tissues.

The incubation period of tetanus is usually 5–10 days, and the disease is characterized by convulsive tonic contraction of voluntary muscles. Prevention of tetanus rests on the proper, prompt surgical care of contaminated wounds and prophylactic use of antitoxin if the individual has not been protected by active immunization with toxoid.