Medical term:

tetanus

Tetanus

Definition

Tetanus is a rare but often fatal disease that affects the central nervous system by causing painful muscular contractions. It begins when tetanus bacteria enter the body, usually through a wound or cut exposed to contaminated soil. Tetanus is easily preventable through vaccination.

Description

Tetanus is rare in the United States, with nearly all cases occurring in adults who were not vaccinated as children. About 100 cases are reported each year; 63% of these occur in people over the age of 50. The number of tetanus cases in the United States has steadily decreased since the 1940s (500 to 600 cases per year); the number of reported cases has remained at approximately 50 to 100 cases per year since the mid-1970s. In 1999, however, the lowest number of annual cases to date was reported (33, or 0.02 per 100,000).

Tetanus causes convulsive muscle spasms and rigidity that can lead to respiratory paralysis and death. It is sometimes called "lockjaw" because one of the most common symptoms is a stiff jaw, unable to be opened. Sometimes, tetanus affects only the part of the body where the infection began, but in almost all of reported cases, it spreads to the entire body. The incubation period from the time of the injury until the first symptoms appear ranges from two to 50 days. Symptoms usually occur within five to 10 days. When symptoms occur early, the chance of death is increased. Tetanus is not contagious.

Causes and symptoms

Tetanus is caused by a bacteria called Clostridium tetani, whose spores (the dormant form) are found in soil, street dust, and animal (or even human) feces. Tetanus spores germinate in the body, producing a highly poisonous neurotoxin in the blood, spreading to the nervous system. The infection is usually transmitted through deep puncture wounds or cuts or scratches that are not cleaned well. Between 1997 and 1999, approximately 64% of tetanus cases in the United States were associated with such wounds as punctures, lacerations, or abrasions. Many people associate tetanus with rusty nails and other dirty objects, but any wound can be a source. Less common ways of getting tetanus are animal scratches and bites, surgical wounds, dental work, and therapeutic abortion. About 18% of cases reported between 1997 and 1999 were a result of intravenous drug use. Cases have also been reported in people with no known wound or medical condition.

The first symptom of tetanus is often a stiff or "locked" jaw that prevents the patient from opening his/her mouth or swallowing. This is also called trismus and results in a facial expression called a sardonic smile (or risus sardonicus). Stiffness of the neck and other muscles throughout the body and uncontrollable spasms often follow. Sometimes these convulsions are severe enough to cause broken bones. The bacterial toxin (tetanospasmin) affects the nerve endings, causing a continuous stimulation of muscles. Other symptoms include irritability, restlessness, loss of appetite, and drooling. People with tetanus that is localized experience pain and tingling only at the wound site and spasms in nearby muscles.

In the underdeveloped world, neonatal tetanus accounts for about one-half of tetanus deaths and is related to infection of the umbilical stump in a baby born of an unimmunized mother. The Centers for Disease Control and Prevention (CDC) estimate that over 270,000 deaths occur annually worldwide as a result of neonatal tetanus. In contrast, only two cases of neonatal tetanus in the United States were reported to the CDC between 1989 and 1999. Mothers who have been adequately immunized against tetanus protect their newborns by passing the antibody through the placenta.

Diagnosis

Tetanus is diagnosed by the clinical symptoms and a medical history that shows no tetanus immunization. Early diagnosis and treatment is crucial to recovery from tetanus.

Treatment

Tetanus is a life-threatening disease that requires immediate hospitalization, usually in an intensive care unit (ICU). Treatment can take several weeks and includes antibiotics to kill the bacteria and shots of antitoxin to neutralize the toxin. It also includes muscle-relaxing drugs to control muscle spasms or barbiturates for sedation. In severe cases, patients are placed on an artificial respirator. Recovery can take six weeks or more. After recovery, since the levels of circulating toxin are too low to stimulate natural antibody production, the patient must still be immunized against this disease to prevent reinfection.

Prognosis

Up to 30% of tetanus victims in the United States die. Early diagnosis and treatment improves the prognosis. Neonatal tetanus has a mortality rate of more than 90%.

Prevention

Pre-exposure vaccination

Tetanus is easily preventable through vaccination. All children should have a series of five doses of DTaP, a combined vaccine that offers protection against diphtheria, tetanus, and pertussis, before the age of seven, according to the Centers for Disease Control and Prevention's national immunization guidelines, the Advisory Committee on Immunization Practices, the Committee on Infectious Diseases of the American Academy of Pediatrics, and the American Academy of Family Physicians. Children will not be admitted to school without proof of this and other immunizations.

The DTaP (diptheria, tetanus, accellular pertussis) vaccine should be given at ages two months, four months, six months, 15 to 18 months, and four to six years. DTaP is the preferred vaccine for children up to the age of seven in the United States; it has fewer side effects than DTP and can be used to complete a vaccination schedule begun with DTP. DTaP was first approved by the Food and Drug Administration (FDA) in September 1996. In December 1996, it was approved for use in infants. Between the ages of 11 and 13, children should have a booster for diphtheria and tetanus, called Td.

Adults should have a Td booster every 10 years. Statistics from the Centers for Disease Control and Prevention (CDC) show that fewer than half of Americans 60 years of age and older have antibodies against tetanus. The CDC suggests adults may be revaccinated at mid-decade birthdays (for example, 45, 55). Adults who have never been vaccinated against tetanus should get a series of three injections of Td over six to 12 months and then follow the 10-year booster shot schedule.

Side effects of the tetanus vaccine are minor: soreness, redness, or swelling at the site of the injection that appear anytime from a few hours to two days after the vaccination and go away in a day or two. Rare but serious side effects that require immediate treatment by a doctor are serious allergic reactions or deep, aching pain and muscle wasting in the upper arms. These symptoms could start from two days to four weeks after the shot and could continue for months.

In early 2001, a shortage of the tetanus vaccine became evident after the pharmaceutical company Wyeth-Ayerst Laboratories decided to stop production of the tetanus vaccine, leaving Aventis-Pasteur as the sole manufacturer of the vaccine. As a result, hospitals were provided with only a minimal amount of the drug on a weekly basis—enough to vaccinate patients with potentially infected wounds and other priority cases. Despite stepped-up production efforts on the part of the manufacturer, however, a spokesperson for Aventis-Pasteur predicted that the shortage would last until the end of 2001, as the vaccine takes 11 months to produce.

Post-exposure care

Keeping wounds and scratches clean is important in preventing infection. Since this organism grows only in the absence of oxygen, wounds must be adequately cleaned of dead tissue and foreign substances. Run cool water over the wound and wash it with a mild soap. Dry it with a clean cloth or sterile gauze. To help prevent infection, apply an antibiotic cream or ointment and cover the wound with a bandage. The longer a wound takes to heal, the greater the chance of infection. If the wound doesn't heal, or, it is red, warm, drains, or swells, consult a doctor.

Following a wound, to produce rapid levels of circulating antibody, a doctor may administer a specific antitoxin (human tetanus immune globulin, TIG) if the individual does not have an adequate history of immunization. The antitoxin is given at the same sitting as a dose of vaccine but at separate sites. Some individuals will report a history of significant allergy to "tetanus shots." In most cases, this occurred in the remote past and was probably due to the previous use of antitoxin derived from horse serum.

Key terms

Clostridium — A genus of deadly bacteria that are responsible for tetanus and other serious diseases, including botulism and gangrene from war wounds. Clostridia thrives without oxygen.

DTaP — Diphtheria and tetanus toxoids and accellular pertussis combination vaccine.

DTP — Diphtheria, tetanus, and whole-cell pertussis vaccine.

Td — Tetanus and diphtheria vaccine.

Toxin — A poisonous substance that flows through the body.

Wound — Any injury that breaks the skin, including cuts, scratches, and puncture wounds.

Resources

Periodicals

Landers, Susan J. "Tetanus vaccine shortage leads to rationing." American Medical News. March 19, 2001. 〈http://www.ama-assn.org/sci-pubs/amnews/pick_01/hlsb0319.htm〉.

Other

"Tetanus." Centers for Disease Control and Prevention. http://www.cdc.gov/nip/publications/pink/tetanus.pdf.

tetanus

[tet´ah-nus]

1. physiological tetanus.

2. a highly fatal disease caused by the bacillus Clostridium tetani, characterized by muscle spasms and convulsions. The bacilli are prevalent in rural areas and grow in the intestines of humans and other animals. They are found in soil and dust, and are spread by animal and human feces, entering the body through a break in the skin, particularly a puncture wound, such as one caused by a nail, splinter, insect bite, or gunshot. Occasionally, the original wound appears trivial and heals quickly; more often, there is obvious infection. Because of the characteristic jaw stiffness, it is also known as lockjaw. adj., adj tetan´ic.

Symptoms. Stiffness of the jaw is usually the first definite indication of tetanus. Difficulty in swallowing, stiffness of the neck, restlessness, irritability, headache, chills, fever, and convulsions are also among the early symptoms. Muscles in the abdomen, back, neck, and face may go into spasm. If the infection is severe, convulsions are set off by slight disturbances, such as noises and drafts. During convulsions, there is difficulty in breathing and the possibility of asphyxiation.

Treatment. If there is any suspicion of contamination by tetanus bacilli, emergency treatment should be obtained. This may include an adequate dose of antitoxin or a booster injection of tetanus toxoid (see below) to counteract any possible tetanus infection. Because of the possible danger of hypersensitivity to horse serum antitoxin, tetanus immune globulin (derived from human instead of horse serum) is preferred when available. In any case, the wound area must be carefully cleaned, and all dead tissue and foreign substances removed.

During a tetanus attack, sedatives are often given to reduce the frequency of convulsions. antibiotics may also be used to help combat secondary infection. hyperbaric oxygenation (oxygen under high pressure) has also been used to treat tetanus.

Prevention. The most important weapon against tetanus is adequate immunization. Tetanus toxoid in combination with diphtheria toxoid and pertussis vaccine (DTP) is given at two months of age and repeated at four months, six months, 18 months, and four to six years of age.

At the time of injury tetanus toxoid is given, either as an initial immunizing dose or as a booster for previous immunization, unless the patient has received a booster or completed the initial immunization within the past five years. Patients who have been actively immunized within the past ten years are given a booster unless they have received a booster within the past five years. Patients who have not been previously immunized may require passive immunity with homologous tetanus immune serum as well as active immunization, especially if the wound is severe, neglected, or over 24 hours old.

Patient Care. Because the toxin from Clostridium tetani attacks the central nervous system it is extremely important to provide a nonstimulating environment for patients with tetanus. The room must be kept dark and quiet, and drafts of cold air, noises, and other external stimuli must be avoided because they may precipitate convulsive muscle spasms. As for any patient subject to convulsions, maintenance of a safe environment is essential. Prevention of injury to and assessment of a patient with convulsive seizures are discussed under convulsion.

Fluids and nourishment usually are given intravenously during the acute stage of the disease. The patient's intake and output are carefully measured and recorded. Sedatives and antibiotic drugs are administered as ordered to reduce irritability and to combat secondary bacterial infections.

As long as the patient is acutely ill and likely to suffer from convulsive seizures, someone should be in constant attendance. Signs of respiratory difficulty, changes in pulse and blood pressure, and frequent and prolonged muscle spasms should be reported immediately. A tracheostomy set should be readily available in the event severe dyspnea should develop.

cephalic tetanus (cerebral tetanus) a rare form of infectious tetanus with an extremely poor prognosis; it may occur following an injury to the head or face or in association with otitis media in which Clostridium tetani is a constituent of the flora of the middle ear and it is characterized by isolated or combined dysfunction of the cranial nerves, especially the seventh cranial. It may remain localized or progress to generalized tetanus.

neonatal tetanus (tetanus neonato´rum) a severe form of infectious tetanus occurring during the first few days of life caused by such factors as unhygienic practice in dressing the umbilical stump or in circumcising male infants and the lack of maternal immunization.

physiological tetanus a state of sustained muscular contraction without periods of relaxation caused by repetitive stimulation of the motor nerve trunk at frequencies so high that individual muscle twitches are fused and cannot be distinguished from one another; called also tetanic or tonic contraction and tetanic or tonic spasm.

tet·a·nus

(tet'ă-nŭs), Avoid the misspelling/mispronunciation tetnus. Do not confuse this word with tetany.

1. A disease marked by painful tonic muscular contractions, caused by the neurotropic toxin (tetanospasmin) of Clostridium tetani acting on the central nervous system. Compare: lockjaw, trismus.

2. A sustained muscular contraction caused by a series of nerve stimuli repeated so rapidly that individual muscular responses are fused, producing a sustained tetanic contraction.

[L. fr. G. tetanos, convulsive tension]

Farlex Partner Medical Dictionary © Farlex 2012

tetanus

(tĕt′n-əs)

1. An acute, often fatal disease characterized by spasmodic contraction of voluntary muscles, especially those of the neck and jaw, and caused by the toxin of the bacterium Clostridium tetani, which typically infects the body through a deep wound. Also called lockjaw.

2. Physiology A state of continuous muscular contraction, especially when induced artificially by rapidly repeated stimuli.

tet′a·nal (tĕt′n-əl) adj.

lockjaw

(1) Tetanus, see there.
(2) Trismus, see there.

tetanus

Lockjaw Infectious disease Acute infection by the anaerobic spore-forming bacillus Clostridium tetani, manifest by uncontrolled muscle spasms due to tetanospasmin; it is often fatal, especially at the extremes of age, and preventable by immunization Epidemiology C tetani is ubiquitous, and may infect virtually any open wound; no longer a major health problem in socioeconomically advanced countries or the US–incidence ± 0.035/105, in developing nations, it is a 'top 10' killer, causing ±1 million deaths/yr Substrate Tetanus develops in a menagerie of mishaps from minor mayhem to sloppy abortions, ♀ circumcision, and so on, rolling rural romanticism into a reality sandwich Clinical ±2 wk incubation, followed by localized or generalized weakness, cramping, dysphagia, trismus–lockjaw, ↑ muscle rigidity–eg, risus sardonicus, opisthotonus, laryngospasm, and ± death Management Benzodiazepines–↓ anxiety, sedation, anticonvulsant, muscle relaxant facilitating GABA-inhibitory transmission in the brain stem and spinal cord, ventilatory support, tetanus immune globulin Vaccine The tetanus vaccine is 96% effective; in the US rates of immunity to tetanus ranges from 80% in white ♂ to < 20% in Mexican-American ♀; immunity is ↑ in those with a ↑ education and income. See Clostridium tetani. Cf Tetany Neurology Tonic muscle contraction, see there.

tet·a·nus

(tet'ă-nŭs)

1. A disease marked by painful tonic muscular contractions, caused by the neurotropic toxin (tetanospasmin) of Clostridium tetani acting on the central nervous system.

2. A sustained muscular contraction caused by a series of nerve stimuli repeated so rapidly that the individual muscular responses are fused, producing a sustained tetanic contraction.
See also: emprosthotonos, opisthotonos

[L. fr. G. tetanos, convulsive tension]

tetanus

A serious infection of the nervous system caused by the organism Clostridium tetani which gains access to the body by way of penetrating wounds. The organism produces a powerful toxin which causes muscles to contract violently, and an early sign is spasm of the chewing muscles (trismus) so that there is great difficulty in opening the mouth (‘lockjaw’). Spasm spreads to the muscles of the face and neck, producing a snarling, mirthless smile (‘risus sardonicus’), and to the back muscles which become rigid. In severe cases, the back becomes strongly arched backwards. There is also fever, sore throat and headache. Death may occur from exhaustion or ASPHYXIA. Tetanus is treated with human antitetanus immunoglobulin and large doses of antibiotics or METRONIDAZOLE. A recent study of 120 patients showed that the intrathecal route for immunoglobulin was more effective than the intramuscular route. Spasms are controlled by intravenous DIAZEPAM but it may be necessary to paralyse the patient temporarily with curare and maintain respiration artificially. Tetanus is easily prevented by immunization with tetanus toxoid. Compare TETANY.

tetanus

a sustained contraction of muscle due to the fusion of many small contractions (twitches) that follow one another in very rapid succession.
a disease produced by toxins from the bacterium Clostridium tetani which usually enters the body through a wound, producing spasm of the voluntary muscle, especially of the jaw (lockjaw) . Bacterial tetanus can be treated by administering antitetanus serum containing ready-made ANTIBODIES, or by antitetanus vaccine which induces the formation of antibodies by the recipient.

tet·a·nus

(tet'ă-nŭs)

1. Disease marked by painful tonic muscular contractions, caused by the neurotropic toxin (tetanospasmin) of Clostridium tetani acting on central nervous system.

2. Sustained muscular contraction caused by a series of nerve stimuli repeated so rapidly that individual muscular responses are fused, producing a sustained tetanic contraction.

[L. fr. G. tetanos, convulsive tension]

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