Disease caused by tetanus toxin, released following infection by the bacterium Clostridium tetani. The bacteria can enter the body through a wound or cut in the skin. They are commonly found in soil, saliva, dust and manure of horses and cows. Tetanus bacteria can survive for a long time outside the body, it can be fatal if left untreated. The case–fatality ratio ranges from 10 to 90%; it is highest in infants and the elderly.
The bacteria can quickly multiply in the body usually within 10 days and release a toxin that affects the nerves causing muscle stiffness and spasms. The muscle stiffness usually involves the jaw (lockjaw) and neck and then becomes generalised. Spasms can be severe that may cause bone fracture.
The bacteria can get into the body through cuts and scrapes, tears and splits on the skin, burns, animal bites, body piercing, tattoos, injections, and eye injuries.
Tetanus can never be eradicated because the spores are commonly present in the environment, on Earth. It occurs in all parts of the world but most frequent cases are in countries with hot and wet climates, throughout Africa, in Asia, and South American countries.
The tetanus vaccine is only given as part of combined products. The vaccine is made from a cell-free purified toxin extracted from a strain of C. tetani. This is treated with formaldehyde that converts it into tetanus toxoid.
They are inactivated, do not contain live organisms and cannot cause the diseases against which they protect.