(lockjaw) n. an acute infectious disease, affecting the nervous system, caused by the bacterium Clostridium tetani. Infection occurs by contamination of wounds by bacterial spores. Bacteria multiply at the site of infection and produce a toxin that irritates nerves so that they cause spasmodic contraction of muscles. Symptoms appear 4–25 days after infection and consist of muscle stiffness, spasm, and subsequent rigidity, first in the jaw and neck then in the back, chest, abdomen, and limbs; in severe cases the spasm may affect the whole body, which is arched backwards (see opisthotonos). High fever, convulsions, and extreme pain are common. If respiratory muscles are affected, a tracheostomy or intubation and ventilation is essential to avoid death from asphyxia. Mortality is high in untreated cases but prompt treatment is effective. An attack does not necessarily confer complete immunity. Immunization against tetanus is effective but temporary. —tetanicadj.
Subjects: Medicine and Health.