Brief overview
- Symptoms: Mouth block, “devil’s grin,” swallowing disorders, laryngeal paralysis, irritability, restlessness, extreme tightening of trunk muscles, hyperextended back to vertebral fracture, respiratory paralysis.
- Causes and risk factors: Infection with Clostridium tetani even via the smallest wounds, spores in soil or animal feces; bacterium multiplies where oxygen is lacking (therefore, superficial wounds are less dangerous than deeper ones)
- Diagnosis: Typical symptoms after injury, detection of the bacterium in the blood
- Treatment: Cutting out of wound edges, administration of antibodies, intensive medical treatment with oxygen supply, ventilation if necessary
- Prognosis: Almost always fatal if untreated, mortality rate up to 20 percent with intensive care treatment
- Prevention: Effective vaccination for all ages, usually starting in infants
What is tetanus?
They enter the human body even through minor injuries. Their toxin then also migrates to the brain and spinal cord. Often, a small cut or a splinter in the skin is enough for infection. Transmission from person to person is not possible with tetanus, so infected persons are not contagious.
What happens in the body
The bacteria produce two toxins:
- One, tetano-lysine, destroys red blood cells and causes damage to the heart.
- The second toxin produced by the bacteria is tetano-spasmin. It travels along nerves and then reaches the central nervous system. The toxin inhibits nerve impulses that normally prevent muscles from contracting too much.
Tetano-spasmin causes the nerves to become highly hyperexcitable. The result is severe, prolonged, excruciating muscle spasms typical of tetanus.
Incubation period
How does tetanus manifest itself?
Tetanus manifests itself primarily in severe, persistent muscle cramps. These affect practically every possible muscle part. Typically, the cramps are triggered by acoustic and visual stimuli as well as touch stimuli.
Mouth lock and devil’s grin
A typical symptom of generalized tetanus is lockjaw. The tongue and jaw muscles tense, resulting in grimacing: constant “smiling” and raised eyebrows, also known as the “devil’s grin.” Patients also fail to open their mouths wide.
Swallowing disorders and paralyzed larynx
If the muscles in the pharynx and larynx are affected, the patient has difficulty swallowing. In extreme cases, patients are unable to speak or scream.
Arched back
In addition, severe spasms develop in the back and abdominal muscles. Affected individuals hyperextend their back in an arching fashion. In extreme cases, such forces develop that even vertebral bodies break.
Other signs of lockjaw include:
- pain and muscle stiffness, especially in the neck and face
- Blood pressure increase
- Sweating
- Palpitations (tachycardia)
- cramps in the limbs
- Breathing problems
- Infants suffering from neonatal tetanus also show marked weakness in drinking.
- General symptoms of illness such as headache, fever, chills. These occur before convulsions in some cases, but often they are absent.
If left untreated, tetanus progresses dramatically. Patients eventually die from paralysis of the respiratory muscles. They remain fully conscious until they die, which makes the suffering particularly agonizing.
Different forms of tetanus
Doctors distinguish between different forms of tetanus:
- The generalized form: In this case, the classic appearance of the disease occurs, with severe cramps all over the body.
- The localized form: Here, the symptoms (such as muscle stiffness) usually remain confined to the part of the body where the pathogen has entered. This is more common when there is residual vaccine protection.
- Cephalic tetanus: In this special form, the infected wound is located on the head. Since the nerve paths to the brain are short here, the incubation period is also short.
- Maternal tetanus: This is when the disease occurs during pregnancy or within the last six weeks before the end of pregnancy.
- Puerperal tetanus: This describes an infection of the mother after a birth or miscarriage. The infection then occurs through the uterus.
- Postoperative tetanus: A tetanus infection following surgical procedures.
What is the cause of tetanus?
The bacterium Clostridium tetani multiplies only under anaerobic conditions, i.e., only where oxygen does not reach.
A superficial wound with a slightly larger surface area is better ventilated than a deeper cut or puncture with a pointed object. Such a wound is therefore less dangerous. On the other hand, a seemingly harmless injury during gardening, such as a prick on a thorn, may be an ideal entry point for the tetanus pathogen.
In addition, the pathogen feels very comfortable in already dead tissue, because an anaerobic environment is also present here. Such dead (necrotic) tissue occurs more frequently in larger wounds, especially if they are not adequately treated surgically.
Animal bites, such as dog bites, also leave deep wounds, which are also a possible entry point for the tetanus pathogens that are found practically everywhere.
Tetanus has nothing in common with blood poisoning. It is true that bacteria are the causative agents in both cases, but different bacteria that lead to different symptoms. Also, the wound in a tetanus infection often does not appear particularly noticeable or inflamed.
Risk factor skin diseases
Skin surface diseases, such as open eczema, favor tetanus infection.
Risk factor age
Old people are more likely to contract tetanus. In them, the antibodies that their bodies have formed after a vaccination often break down more quickly than in younger people. They therefore need booster vaccinations at shorter intervals. If this does not happen, they are less well protected.
Examinations and diagnosis
The doctor makes the diagnosis of tetanus on the basis of the typical clinical findings: if muscle stiffness or cramps occur as a result of a wound injury, the diagnosis of tetanus is usually clear. For further diagnosis, tests are available with which the toxin of the tetanus bacteria can be detected in the wound material or in the blood serum (neutralization test). However, these are not always conclusive. In the case of a tetanus infection, however, the wound itself is usually inconspicuous and looks “normal”.
Treatment
Three basic rules apply to the treatment of tetanus:
- Identification of the site of entry and excision of the wound edges (wound debridement).
- Neutralization of the tetanus toxin and immunization
- Supportive measures against the symptoms
Injecting antibodies
To neutralize the circulating tetanus toxin, inject antibodies (immunoglobulins) against the tetanus toxin into the buttock muscles and wound edges instead.
Keeping the airways open
Since the facial and laryngeal muscles spasm in tetanus, the airways must be specifically kept open. The patient receives oxygen via a nasal tube. Artificial respiration on a respiratory machine is also often necessary. The doctors treat the muscle spasms with special medications known as muscle relaxants.
Dark and quiet
As a rule, the patient is moved to a darkened and noiseless room. This isolates the patient from external stimuli. Otherwise, acoustic or visual stimuli often trigger further cramps, which is largely prevented by the doctors.
Course of the disease and prognosis
Tetanus should not be underestimated. The tetanus symptoms are not only associated with considerable pain for those affected, but also usually lead to death if left untreated.
However, since intensive medical therapy is usually started in good time, this can be prevented in many cases. After about four weeks, the symptoms gradually recede, and after another four weeks they disappear completely. Occasionally, secondary damage remains that requires further treatment. Nevertheless, the mortality rate is around 20 percent even with treatment.
Tetanus disease does not produce immunity, which means that it is possible for the person to contract the same infection again. Therefore, complete immunization (= vaccination) and regular booster vaccinations against tetanus are important.
Prevention with the tetanus vaccination
In general, physicians recommend tetanus vaccination for people of all ages. Basic immunization is given to infants and should be completed before the first birthday. This is followed by boosters at ages five to six and nine to 16. From the last immunization, a booster is recommended every ten years.
You can find out what to look out for when vaccinating against tetanus in the article Tetanus – Vaccination.
