Tetanus (Lockjaw)

1.Identification: an acute disease induced by an exotoxin of the tetanus bacillus, which grows anerobically at the site of an injury. It is characterized by painful muscular contractions, primarily of the masseter and neck muscles, secondarily of trunk muscles. A common first sign suggestive of tetanus in older children and adults is abdominal rigidity, though rigidity is sometimes confined to the region of injury. Generalized spasms occur, frequently induced by sensory stimuli.

Typical features of tetanic spasm are the position of opisthotonos and the facial expression known as “risus sardonicus”. History of an injury or apparent portal of entry may be lacking. Case – fatality rate ranges from 10% to over 80% depending on age and quality of care available, is highest in infants and the elderly, and varies inversely with the length of the incubation period and the availability of experienced intensive care unit personnel and resources.

Infectious agent: Clostridium tetani, the tetanus bacillus Infectious agent: Clostridium tetani, the tetanus bacillus. Occurrence: worldwide, the disease is more common in agricultural regions and in areas where contact with animal excreta is more likely and immunization is inadequate. Parenteral use of drugs by addicts, intramuscular or subcutaneous use, can result in individual cases and occasional circumscribed outbreaks.

4.Reservoir : intestines of horses and other animals, humans in which the organism is a harmless normal inhabitant. Soil or fomites contaminated with animal and human feces. Tetanus spores, ubiquitous in the environment, can contaminate wounds of all types. 5.Mode of transmission : tetanus spores are usually introduced into the body through a puncture wound contaminated with soil, street dust or animal or human feces; through lacerations, burns and trivial or unnoticed wounds; or by injected contaminated drugs (e.g. street drugs). Tetanus occasionally follows surgical procedures, which include circumcision and abortions performed under unhygienic conditions. The presence of necrotic tissue and/or foreign bodies favors growth of the anerobic pathogen.

6.Incubation period: usually 3 – 21 days, although it may range from 1 day to several months, depending on the character, extent, and location of the wound; average 10 days. Most cases occur within 14 days. In general, shorter incubation periods are associated with more heavily contaminated wounds, more sever disease, and a worse prognosis. 7.Period of communicability: no direct person to person transmission. 8.Susceptibility and resistance: susceptibility is general. Active immunity is induced by tetanus toxoid and persists for at least 10 years after full immunization ; transient passive immunity follows injection of tetanus immune globulin (TIG) or tetanus antitoxin (equine origin). Infants of actively immunized mothers acquire passive immunity that protects them from neonatal tetanus. Recovery from tetanus may not result in immunity; second attacks can occur and primary immunization is indicated after recovery.

9. Methods of control: A. Preventive measures: 1 9.Methods of control: A. Preventive measures: 1.Educate the public on the necessity for complete immunization with tetanus toxoid, the hazards of puncture wounds and closed injuries that are particularly liable to be complicated by tetanus, and the potential need after injury for active and / or passive prophylaxis. 2.Active immunization withadsorbed tetanus toxoid (TT) which gives durable protection for at least 10 years; after the initial basic series has been completed, single booster doses elicit high levels of immunity. In children under 7 , the toxoid is generally administered together with diphtheria toxoid and pertussis vaccine as atriple (DTP) antigen or as (DT) antigen.Tetanus and diphtheria (Td) vaccine is used for children older than 7 years .

In countries with incomplete immunization programs for children , all pregnant women should receive 2 doses of tetanus toxoid in the first pregnancy , with an interval of at least 1 month , and with the second dose at least 2 weeks prior to child birth , in order to prevent maternal and neonatal tetanus . Booster doses may be necessary to ensure ongoing protection. Minor local reactions following tetanus toxoid injections are relatively frequent ; sever local and systemic reactions are infrequent but do occur , particularly after excessive numbers of prior doses have been given.

a) The schedule recommended for tetanus immunization in childhood is the same as for diphtheria. b) While tetanus toxoid is recommended for universal use regardless of age , it is especially important for workers in contact with soil , sewage and domestic animals;members of military forces; policemen and others with greater than usual risk of traumatic injury; adults with diabetes mellitus ; older adults who are currently at highest risk for tetanus and tetanus related mortality; and women of reproductive age and newborns.Vaccine – induced maternal immunity is important in preventing maternal and neonatal tetanus. c) Active protection should be maintained by administrating booster doses of Td every 10 years.

d) For children and adults who are severely immunocompromized or infected with HIV, tetanus toxoid is indicated in the same schedule and dose for immunocompetent persons, even though the immune response may be suboptimal. 3.Prophylaxis in wound management : tetanus prophylaxis in patients with wounds is based on careful assessment of whether the wound is clean or contaminated, the immunization status of the patient , proper use of tetanus toxoid and / or TIG, wound cleaning , and – where required – surgical debridement and the proper use of antibiotics.

a)Those who have been completely immunized and who sustain minor and uncontaminated wounds require a booster dose of toxoid only if more than 10 years have elapsed since the last dose was given. For major and / or contaminated wounds , a single booster injection of tetanus toxoid should be administered promptly on the day of injury if the patient has not received tetanus toxoid withen the preceding 5 years. b) Persons who have not completed a full primary series of tetanus toxoid require a dose of toxoid as soon as possible following the wound , and may require passive immunization with human TIG if the wound is a major one and / or if it contaminated with soil containing animal excreta. DTP,DT or Td, as determined by the age of the patient and previous immunization history, should be used at the time of the wound ,and ultimately to complete the primary series.

Passive immunization with at least 250 IU of human – derived TIG IM (or 1500 to 5000 IU of antitoxin of animal origin if globulin is not available), regardless of the age of the patient, is indicated for patients with other than clean , minor wounds and a history of no, unknown or fewer than 3 previous tetanus toxoid doses. When tetanus toxoid and TIG or antitoxin are given concurrently, separate syringes and separate sites must be used.

Antibiotics may theoretically prevent the multiplication of C Antibiotics may theoretically prevent the multiplication of C. tetani in the wound and thus reduce the production of toxin , but this does not obviate the need for prompt treatment of the wound together with appropriate immunization . B. Control of patient , contacts and the immediate environment : Report to local health authority Isolation : not applicable Concurrent disinfection : not applicable Quarantine : not applicable Immunization of contacts : not applicable

6)Investigation of contacts and source of infection : case investigation to determine circumstances of injury 7)Specific treatment : TIG IM in doses of 3000- 6000 IU. If tetanus IG is not available, tetanus antitoxin (equine origin) in a single large dose should be given IV following testing for hypersensitivity. Metronidazole, the most appropriate antibiotic in terms of recovery time and case – fatality , should be given for 7 – 14 days in large doses ; this also allows for a reduction in the amount of muscle relaxant and sedative required . The wound should be debrided widely if possible. Wide debridement of the umbilical stump in neonates is not indicated . Maintain an adequate airway and employ sedation as indicated ; muscle relaxant drugs , together with tracheostomy or nasotracheal intubation and mechanically assisted respiration , may be life saving .Active immunization should be initiated concurrently with treatment.

C.Epidemic measures : In the rare outbreak, search for contaminated street drugs or other common –use injections. D.Disaster implications: military conflicts and natural disasters (floods, earthquakes) that can cause many traumatic injuries in non- immunized populations will result in an increased need for TIG or tetanus antitoxin and toxoid for injured patients. E.International measures: Up-to-date immunization against tetanus is advised for injured patients.

Tetanus Neonatorum It is a serious health problem in many developing countries where maternity care services are limited and immunization against tetanus is inadequate .In the past 10 years the incidence of tetanus neonatorum has declined considerably in many developing countries, thanks to improved training of birth attendants and immunization with tetanus toxoid for women of childbearing age.

Despite this decline, WHO estimated in 2006 that tetanus neonatorum still caused about 257000 deaths , mainly in the developing world. Most newborn infants with tetanus are born to non-immunized mothers delivered by an untrained birth attendant outside a hospital. The disease usually occurs through introduction of tetanus spores via the umbilical cord, during delivery through the use of an unclean instrument to cut the cord , or after delivery by dressing the umbilical stump with substances heavily contaminated with tetanus spores.

Tetanus neonatorum is typified by a newborn infant who sucks and cries well for the first few days after birth but subsequently develops progressive difficulty and then inability to feed because of trismus , generalized stiffness with spasms or convulsions and opisthotonos. The average incubation period is about 6 days , with a range from 3 to 28 days. Overall, case – fatality rates for neonatal tetanus are very high, exceeding 80% among cases with short incubation periods. Neurological sequelae including mild retardation occur in 5% to over 20% of those children who survive .

Prevention : 1.Improving maternity care , with emphasis on increasing the tetanus toxoid immunization coverage of women of childbearing age (especially pregnant women) and clean deliveries. 2.Increasing the proportion of deliveries attended by trained attendants.

Non – immunized pregnant women should receive at least 2 doses of tetanus toxoid , preferably as Td, according to the following schedule: the first dose at initial contact or as early as possible during pregnancy ; the second dose 4 weeks after the first and preferably at least 2 weeks before delivery. A third dose could be given 6-12 months after the second .An additional 2 doses should be given at annual intervals.