Tetanus

Tetanus is an infectious disease caused by contamination of wounds from bacteria that live in the soil. The causative bacterium Clostridium tetani is a hardy organism capable of living many years in the soil in a form called a spore.

Tetanus occurs when a wound becomes contaminated with bacterial spores. Infection follows when spores become activated and develop into gram-positive bacteria that multiply and produce a very powerful toxin (poison) that affects the muscles. Tetanus spores are found throughout the environment, usually in soil, dust, and animal waste. The usual locations for the bacteria to enter your body are puncture wounds, such as those caused by rusty nails, splinters, or insect bites. Burns, any break in the skin.

Four possible types

1. Generalized tetanus can affect all skeletal muscles. It is the most common as well as the most severe form of the four types
2. Local tetanus manifests with muscle spasms at or near the wound that has been infected with the bacteria
3. Cephalic tetanus primarily affects one or several muscles in the face rapidly (in one to two days) after a head injury or ear infection
4. Neonatal tetanus is similar to generalized tetanus except that it affects a baby that is less than 1 month old (called a neonate). This condition is rare in developed countries

Tetanus Causes

• Clostridium tetani is the type of bacteria responsible for the disease. The bacteria are found in two forms: as a spore (dormant) or as a vegetative cell (active) that can multiply
• The spores are in soil, dust, and animal waste and can survive there for many years. These spores are resistant to extremes of temperature
• Contamination of a wound with tetanus spores is rather common. Tetanus, however, can only occur when the spores germinate and become active bacterial cells
• The active bacterial cells release two exotoxins, tetanolysin and tetanospasmin. The function of tetanolysin is unclear, but tetanospasmin is responsible for the disease.
• The disease typically follows an acute injury that results in a break in the skin. Most cases result from a puncture wound, laceration (cut), or an abrasion (scrape).
• Other tetanus-prone injuries include the following:
• Surgery
• Crush wound
• Abscesses
• Childbirth and
• Drug users (site of needle injection).
• Wounds with devitalized (dead) tissue (for example, burns or crush injuries) or foreign bodies (debris in them) are most at risk of developing tetanus
• Tetanus may develop in people who are not immunized against it or in people who have failed to maintain adequate immunity with active booster doses of vaccine

Tetanus Symptoms

In generalized tetanus, the initial complaints may include any of the following:

• Irritability, muscle cramps, sore muscles, weakness, or difficulty swallowing are commonly seen
• Facial muscles are often affected first. Trismus or lockjaw is most common. This condition results from spasms of the jaw muscles that are responsible for chewing.
• Muscle spasms are progressive and may include a characteristic arching of the back known as opisthotonus. Muscle spasms may be intense enough to cause bones to break and joints to dislocate
• Severe cases can involve spasms of the vocal cords or muscles involved in breathing
• In cephalic tetanus, in addition to lockjaw, weakness of at least one other facial muscle occurs. In two-thirds of these cases, generalized tetanus will develop
• In localized tetanus, muscle spasms occur at or near the site of the injury. This condition can progress to generalized tetanus
• Neonatal tetanus is identical to generalized tetanus except that it affects the newborn infant. Neonates may be irritable and have poor sucking ability or difficulty swallowing

Prevention of Tetanus

• Tetanus is completely preventable by active immunization. Tetanus toxoid has proven to be safe since its introduction during the 1920s. Tetanus toxoid consists of inactivated tetanus toxin treated with chemicals or heat to decrease the toxic effect, but to retain its antigenic power
• Tetanus toxoid is available by itself, or frequently as one of three components in a vaccine. It can be combined with diphtheria toxoid and pertussis vaccine (DTP) for primary immunization of children, and with reduced diphtheria toxoid (Td) for immunization of older adults and children
• For primary immunization in adults, tetanus toxoid is given in two doses 4 to 6 weeks apart, with a third dose 6 to 12 months later. Booster doses are recommended every 10 years to ensure the maintenance of protective antitoxin levels
• Immunization is especially recommended for adults 50 years and older since most tetanus cases in recent years have occurred in this age group. Tetanus should be considered for:
  • persons who are not sure whether they have received the initial series of boosters
  • travelers to foreign countries with hot, damp climates
  • agricultural workers who work with dirt or manure
  • persons whose jobs expose them to cuts and scrapes

• Pregnant women who have not been immunized or may be inadequately immunized or who may deliver their infants in unhygienic circumstances. After immunization, antibodies to the disease are passed from the mother to the fetus through the placenta.

Source: emedicinehealth