Tetanus, also called lockjaw, is a serious infection caused by Clostridium tetani; this bacterium produces a toxin that affects the brain and nervous system, leading to stiffness in the muscles.

If Clostridium tetani spores are deposited in a wound, the neurotoxin interferes with nerves that control muscle movement.

The infection can cause severe muscle spasms, serious breathing difficulties, and can ultimately be fatal. Although tetanus treatment exists, it is not uniformly effective. The best way to protect against tetanus is to take the vaccine.

Causes of tetanus :

Tetanus is caused by the Clostridium tetani bacterium. Clostridium tetani spores are able to survive for a long time outside of the body. They are most commonly found in animal manure and contaminated soil, but may exist virtually anywhere.

When Clostridium tetani enter the body, they multiply rapidly and release tetanospasmin, a neurotoxin. When tetanospasmin enters the bloodstream, it rapidly spreads around the body, causing tetanus symptoms.

Tetanospasmin interferes with the signals traveling from the brain to the nerves in the spinal cord, and then on to the muscles, causing muscle spasms and stiffness.

Puncture wounds – Clostridium tetani enters the body mainly through skin lesions (skin cut or puncture wound). Thoroughly cleaning any cut helps prevent an infection from developing.

Common ways of contracting tetanus

• Wounds that have been contaminated with saliva or feces
• Burns
• Crush injuries
• Wounds that include necrotic (dead) tissue
• Puncture wounds

Rare ways of contracting tetanus

• Surgical procedures
• Superficial wounds
• Insect bites
• Compound fractures
• Intravenous drug use
• Injections into the muscle (intramuscular)
• Dental infections

Symptoms of tetanus

Tetanus symptoms usually emerge about 7-10 days after initial infection; however, this can vary from 4 days to about 3 weeks, and, in some cases, it may take months.

In general, the further the injury site is from the central nervous system, the longer the incubation period. Patients with shorter incubation times tend to have more severe symptoms.

Muscle symptoms – spasms and muscular rigidity (muscles become stiff). Stiffness usually starts with the chewing muscles, hence the name lockjaw.

Muscle spasms then spread to the neck and throat, causing dysphagia (difficulty swallowing). Patients often go on to have spasms in their facial muscles.

Breathing difficulties may result from neck and chest muscle stiffness. With some patients, abdominal and limb muscles are also affected.

In severe cases, the spine will arch backward as the back muscles are affected – this is more common when children are infected.

Most patients with tetanus will also have the following symptoms:

• Bloody stools (feces)
• Diarrhea
• Fever
• Headache
• Sensitivity to touch
• Sore throat
• Sweating
• Tachycardia (rapid heartbeat)

Complications

If the patient does not receive treatment, the risk of life-threatening complications is higher – mortality rates vary from 40-76 percent – symptoms may include:

• Fractures – sometimes, in severe cases, the muscle spasms and convulsions may lead to bone fractures.
• Aspiration pneumonia – if secretions or contents of the stomach are inhaled, a lower respiratory tract infection can develop, leading to pneumonia.
• Laryngospasm – the larynx (voice box) goes into a spasm which can last up to a minute and cause breathing difficulties. In severe cases, the patient can suffocate.
• Tetanic seizures – if infection spreads to the brain, the patient can have epileptic-like fits (seizures).
• Pulmonary embolism – a blood vessel in the lung can become blocked and affect breathing and circulation. The patient will urgently need oxygen therapy and anti-clotting medication.
• Severe kidney failure (acute renal failure) – severe muscle spasms can result in the destruction of skeletal muscle which can cause myoglobin – a muscle protein – to leak into the urine. This can cause acute renal failure (severe kidney failure).

Prevention of tetanus

Most cases of tetanus occur in people who have never been immunized (never had the vaccine), or who did not have a booster shot within the preceding decade.

The tetanus vaccine

The tetanus vaccine is routinely given to children as part of the DTaP (diphtheria and tetanus toxoids and acellular pertussis) shot. The DTaP vaccine consists of five shots, usually given in the arm or thigh of children when they are aged:

• 2 months
• 4 months
• 6 months
• 15 – 18 months
• 4 – 6 years

A booster is normally given between the ages of 11 and 18 years, and then another booster every 10 years. If an individual is traveling to an area where tetanus is common, they should check with a doctor regarding vaccinations.