Tetanus - Major Public Health Problem

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The prognosis of Tetanus is dependent on the incubation period, the time it takes from spore inoculation to first symptom appearing. The incubation period usually ranges from 3 to 21 days, generally about 8 days (CDC 292). This may be related to the amount of toxin present at the site of wound and the immunization status of the patient during the time of infection (292). In general the further the injury site is from the central nervous system, the longer the incubation period (292). Shorter incubation periods are associated with a severer form of the disease and a higher chance of death (292).

There are four clinical forms of this disease that are recognized depending upon the extent and location of neurons involved (NeurologyIndia 398). Localized tetanus is a relatively uncommon form of the disease, in which patients have persistent contraction of the muscles in same anatomic area as the injury preceding the tetanus (CDC 292). Cephalic tetanus is a rare form of the disease, which commonly results from middle ear infections in which C. tetani is present in the flora of the middle ear, or following injuries to the head (292). It involves the cranial nerves in the facial area. Generalized tetanus is the most common form of the disease and is responsible for about 80% of all reported tetanus cases (292). It is characterized by increased muscle tone and generalized spasms (292). Usually, the first sign is difficulty in opening the jaw, due to an increased muscle tone of the masseters (trismus or lockjaw), a muscle in the cheek that functions to close the jaw (Hinfey 1). The disease usually presents with a descending pattern, so subsequently, there is a spread to other body parts (CDC 292). Spasms may occur frequently and last for several minutes which can continue for up to 3–4 weeks (292). The last form of the disease is neonatal tetanus. It is a form of generalized tetanus that occurs in newborn infants (292). The common age of onset is between 5 and 15 days following birth (NeurologyIndia 400). Neonatal tetanus occurs in infants born without protective passive immunity, because the mother is not immune. It usually occurs through infection of the unhealed umbilical stump, particularly when the stump is cut with an unsterile instrument (292). Neonatal tetanus is common in some developing countries, but is very rare in the United States.

Signs and symptoms of tetanus may appear anytime from a few days to several weeks after tetanus bacteria enter your body through a wound. Common signs and symptoms of tetanus, in order of appearance, are: spasms and stiffness in your jaw muscles, stiffness of your neck muscles, difficulty swallowing, stiffness of your abdominal muscles, painful body spasms, lasting for several minutes, typically triggered by minor occurrences, such as a draft, loud noise, physical touch or light (Mayo Clinic 1). Other signs and symptoms may include: fever, sweating, seizures, and difficulty breathing (1). Also hyperactivity of the autonomic nervous system may result, which may lead to hypertension and/or an abnormal heart rhythm (CDC 293).

There are several grading systems on grading the severity of tetanus. The scale proposed by Ablett is the most simple and widely used today (Taylor 102). It categorizes patients into four grades depending upon the intensity of spasms, respiratory rates and autonomic involvement (102).

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Ablett Classification of the Severity of Tetanus. 2002. Photograph. Tspace.library.utoronto.ca. By R. Bhatia, S. Prabhakar, and V. K. Grover. Departments of Neurology and Anesthesia of India, Aug. 2002. Web. 2 Apr. 2013.

Since there’s no cure for tetanus, doctors primary treat tetanus symptomatically (Mayo Clinic 1). The diagnosis of tetanus is primarily clinical. Doctors diagnose tetanus primarily based upon a physical exam, medical and immunization history, and the signs and symptoms of muscle spasms, stiffness and pain (1). There are no laboratory tests that are helpful for diagnosing tetanus (CDC 293). The medical treatment has one primary goal in mind: to limit the growth and eventually kill the infecting C. tetani and thus eliminating the toxin production. One way is through wound management, which is essential to preventing growth of tetanus spores. Doctors do this by cleaning the wound to remove any dirt, foreign objects and dead tissue from the wound (Mayo Clinic 1). It eradicates the spores and changes the conditions for germination, thereby preventing further elaboration and absorption of the neurotoxin (Neurology India 1). Doctors will generally give their patients a tetanus antitoxin called, tetanus immune globulin (TIG). TIG only helps remove and neutralize any unbound tetanus toxin (Mayo Clinic 1). Once the toxin becomes bound to the neurons, it cannot be neutralized with antitoxin (1). Intravenous immune globulin (IVIG) containing the tetanus antitoxin may be used if TIG is not available (CDC 293). Antibiotic therapy may also be used. Penicillin and metronidazole are the two major drugs used routinely to try to fight against the bacteria (Neurology India 402). Doctors will generally use powerful sedatives and muscle relaxants called benzodiazepines to help control the muscle spasms (402). With diazepam (Valium) being the most commonly used drug of this class (402). Other medications, such as magnesium sulfate and certain beta blockers, may be used to help regulate involuntary muscle activity, such as your heartbeat and breathing (Mayo Clinic 1). Because of the extreme potency of the toxin, a tetanus infection does not result in tetanus immunity (CDC 294). Active immunization with tetanus toxoid should begin or continue as soon as the person’s condition has stabilized.

A person can easily prevent contracting tetanus by being immunized against the toxin. Almost all cases of tetanus occur in people who’ve never been immunized or who haven’t had a tetanus booster shot within the previous 10 years. The vaccine is made of inactivated toxins from the bacteria Clostridium tetani (CDC 296). The tetanus toxoid consists of a formaldehyde-treated toxin (296). These vaccines are made by chemically treating the tetanus toxins to render them nontoxic but yet still capable of eliciting an immune response in the vaccinated person (Tetanus: Q&A 2). It induces an antibody response in it hosts and stops C. tetani from causing tetanus. They are known as “inactivated” vaccines because they do not contain live bacteria and cannot replicate themselves, which is why multiple doses are needed to produce immunity (2). There are two types of toxoids available, an adsorbed (aluminum salt precipitated) toxoid and fluid toxoid (CDC 296). The adsorbed toxoid is preferred because the antitoxin response reaches higher titers and is longer lasting than that following