Tetanus is an acute disease caused by a neurotoxin produced by the obligately anaerobe Gram positive, spore-forming bacterium Clostridium tetani. Simply said, tetanus is caused by a toxin released by a common dust or soil bacterium. It has a worldwide distribution
Clostridium tetani spores are ubiquitous in the environment and are a normal inhabitant of soil, and animal and human intestines. After entering the body through a wound, the spores germinate and produce toxins. These toxins interfere with the release of neurotransmitters at inhibitory nerve terminals resulting in unopposed muscle contraction and spasm. Tetanus occurs worldwide but is more common in hot, damp climates with soil rich in organic matter. Tetanus, particularly the neonatal form, remains a significant public health problem in non-industrialised countries, causing an estimated 400,000 deaths each year. Generalised tetanus occurring in newborns is termed neonatal tetanus, and this form of tetanus is attributable to low maternal immunity in combination with non-sterile delivery and certain traditional umbilical cord care practices. In industrialised countries tetanus has become very uncommon, particularly amongst infants band children, due to effective childhood immunisation programmes
More recently, Tetanus has been described in Intravenous Drug Users (IDU), where potential sources for infection are contaminated drugs, paraphernalia, and contaminated skin. Increased awareness of tetanus in IDUs is therefore extremely important.
The incubation period ranges from 3 days to 3 weeks, usually around 7-8 days. Longer incubation periods may be associated with more peripheral injury sites.
The onset of symptoms is gradual, over 1 to 7 days. It is characterised by painful muscle contractions mainly in the neck and face, but also in the trunk. In general, the shorter the incubation period the more severe the disease and the higher the risk of death.
A number of clinical forms of tetanus have been described. Generalised tetanus is the most common and is characterised by increased muscle tone and generalised spasms. These spasms are violent and painful and may threaten ventilation. Sustained contraction of the facial muscles results in the classic sign of risus sardonicus. Sustained contraction of the back muscles produces an arched back ( opisthotonos ). Generalised tetanus occurring in newborns is termed neonatal tetanus . Local tetanus is uncommon and is characterised by persistent contraction in the same area as the injury. Cephalic tetanus is rare and involves cranial nerves, particularly in the facial area.
Clinical evidence of tetanus infection is defined as mild to moderate trismus and one or more of the following: spasticity, dysphagia, respiratory embarrassment, spasms, and autonomic dysfunction.
Because the disease is very rare, a diagnosis of tetanus may not be initially recognised. Laboratory tests are of limited value as the organism may be isolated from a wound in as few as 30% of cases. Furthermore Clostridium tetani can be isolated from patients who do not have the disease. Diagnosis thus relies upon clinical criteria. The current clinical case definition for tetanus is acute onset of:
Hypotonia and / or painful muscle contractions (most commonly in the jaw and neck), and which may proceed to generalised muscle spasms.
Clinical signs may also be rather non-specific, particularly in the early stages of the disease and in neonates who may present with apnoea or tonal abnormalities without the classic opisthotonos.
In general the specialist treatment will involve the following:
the cleaning and debridement of wounds
the giving of human tetanus immune globulin
early ventilation and sedation, as required, and if symptoms progress
the control of spasms with diazepam, or phenobarbitone.
Effective individual protection against tetanus can only be achieved through active immunisation. Unlike other vaccine-preventable diseases, there is no possibility of herd immunity and immunity cannot be naturally acquired. Vaccination with tetanus toxoid stimulates production of antibodies which act against the toxin produced by the organism thus providing protection against the consequences of infection rather than the infection itself. Immunisation with a toxoid ought to prevent the disease, but waning immunity and/or increased immigration of non-immunised or inadequately immunised individuals represent a significant cause of cases in developed nations.
Wounds that may permit tetanus spores to germination:
classic wounds such as burns, compound fractures, wounds with extensive damage
injecting drugs users had contributed to a higher incidence in your adults
body piercing