Tetanus

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. The toxin blocks signaling that normal allows for relaxation of muscles at the appropriate time; therefore, it causes abnormal continuous muscle contraction that in its most severe form can cause death.

Symptoms of tetanus usually begin 5 to 10 days after a wound or umbilical cord has been infected. However, the symptoms may occur as early as 2 days and as late as 50 days after exposure.

The onset occurs slowly over a few days to a week. Muscle spasms start out in a mild fashion in one specific part of the body and remain in that distribution or spread to involve all muscles. The most frequent symptom is a stiff jaw. This is caused by spasm of the muscle that closes the mouth. This accounts for the disease's familiar name "lockjaw." The spasms may then become severe and spread throughout the body.

Other symptoms of tetanus include the following:

• arrhythmias, or irregular heartbeats
• pain during muscle spasms
• difficulty breathing
• difficulty swallowing
• high blood pressure
• irritability
• neck pain or stiffness
• restlessness
• seizures

Tetanus is caused by a toxin made by the bacteria. 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.

Those at risk of tetanus include:

• newborns where the umbilical stump is infected
• women who develop infection after an abortion
• people with diabetes with infected foot or leg wound
• people after surgery involving the bowel
• a person with any puncture wound especially from a soiled or rusty object or an animal bite
• a drug addict who uses dirty needles

Tetanus toxoid can prevent this disease. This toxoid is usually combined with the diphtheria toxoid and acellular pertussis vaccine in the DTaP (for children) or Tdap (for adolescents and adults) immunization. It is initially given in early childhood. Booster shots are needed every 5 to 10 years to maintain immunity. For high-risk wounds in a person who has never been immunized or has not had the complete series of injections, tetanus immune globulin can be used to prevent tetanus.

Diagnosis of tetanus is based primarily on a medical history and physical examination.

The toxin blocks the transmission of signals irreversibly. No treatment is available to remove the toxin. A person with tetanus is supported medically, sometimes on a ventilator, for weeks until the toxin breaks down.

During that time, the individual is at risk for other infections simply because of exposure to them during their prolonged hospital course. When tetanus has generalized throughout the body, death is frequent either from the effects of the toxin or from complications incurred during the hospital stay.

Tetanus is not contagious from person to person.

The goals of tetanus treatment are to eliminate the source of toxin and prevent muscle spasms. Treatment of tetanus includes the following:

• antibiotics to rid the body of any remaining toxin producing bacteria
• drainage and cleaning of infected wounds
• muscle relaxants
• pain control
• tetanus immune globulin is injected into the blood stream and will bind any tetanus toxin not already bound to nerve receptors
• cardiac medications to treat heart irregularities and blood pressure fluctuations
• supportive care such as the use of a ventilator (artificial breathing machine) if breathing is impaired

Allergic reactions may occur with any drug. A prolonged hospital course increases the risks of other infections.

The mortality rate from tetanus is about 25% in the United States and 50% worldwide. Most people recover from tetanus completely. Recovery can take months.

Individuals with tetanus are generally treated in the intensive care unit. After discharge, the person needs to make periodic visits to the healthcare professional, to whom any new or worsening symptoms should be reported.