A severe, sometimes fatal disease of the central nervous system (brain and spinal cord) caused by infection of a wound with spores of the bacterium CLOSTRIDIUM TETANI.
The spores live mainly in manure and soil but are also found elsewhere , including in the human intestine. When the spores infect poorly oxygenated tissues they multiply and produce a toxin that acts on the nerves in charge of controlling muscle activity.
The most frequently seen symptom is trismus (stiffness of the jaw, known widespread as lock-jaw . other symptoms include aching and stiffness of the abdominal and back muscles, and contraction of facial muscles, giving a fixed grimace. There can also be a rapid pulse, profuse sweating and, a mild fever. Painful muscles spasms then develop, and can result in asphyxia if they affect the chest wall or larynx. The spasms generally stop after ten to fourteen days.
The diagnosis is made from the symptoms and signs, and a course of tetanus antitoxin injections is started. Artificial ventilation may be required. Many people recover completely if treated immediately.
In the United Kingdom tetanus is prevented by routine immunisation, with three doses during the first year (at two, three, and four months of age), a booster at three years four months to five years and another booster at 13 to 18 years of age. Usually, five doses of the vaccine give lifelong immunity, although further boosters can be necessary after a dirty wound or if travelling in an area with poor medical services.