Tetanus a lockjaw infection: symptoms, types, treatment, and preventive measures

 

What is Tetanus?

Tetanus is an infection caused by the bacteria Clostridium tetani. This bacterium is a slender-shaped obligate anaerobe (it grows in the absence of oxygen). The problem associated with the infection is called "Lockjaw". In this condition, the person is unable to open its mouth and swallow due to severe stiffness in the neck and jaw muscles. Spasms can also occur in chest and abdominal muscles. Sometimes, severe muscle spasms may occur in back muscles, leading to arching of the back with the head bent backwards, causing a very uncomfortable and painful posture.

How Does it Cause Spasms or Muscle Stiffness?

This occurs when Clostridium tetani releases an exotoxin (Tetanospasmin, a protein-based neurotoxin) into the bloodstream. This neurotoxin has a high affinity for the neuromuscular junction. Tetanospasmin interferes with the action of neurotransmitters, gamma-aminobutyric acid (GABA), and glycine, which are known to relax muscle activity. In the absence of GABA, uncontrolled and forceful muscle contractions occur, leading to muscle stiffness and spasms. Some muscle contractions are so forceful that they can even cause bone fractures.

 

Tetanus: infection process and symptoms

Infection

These bacteria produce spores which may be present anywhere in dust, soil, and feces. The spores are resistant to boiling and freezing and can remain viable (capable of life) for many years in the environment. The spores can enter the body through a wound or cut caused by any sharp object (such as rusty nails) or a scratch. However, it cannot be transferred from one person to another. Inside the body, the spores break down to release the actively growing bacteria.

Bacteria "Clostridium Tetani" and its spores

After the entry of bacteria into the body, it may take 3 to 21 days to cause the infection or symptoms. This time period is called the incubation period, which depends on the load of bacterial cells entered and the immune status of the person. The symptoms may include:

·    Cramps in jaw and neck muscles.

·    Pain and stiffness in the body.

·    Involuntary muscle spasms.

·    Difficulty in swallowing and breathing

·    Fever and headache.

 

Serious Complications May Include:

·    Uncontrolled tightening of vocal cords.

·    Fractures in bones due to forceful contraction of muscles.

·    Blockage in blood vessels of lungs affects breathing.

·    Due to severe muscle spasms, excessive release of muscle protein in the blood may cause kidney damage.

·    In 10% of cases, tetanus can lead to death.

 

Types of Tetanus:

It is based on the route of bacterial entry, severity of symptoms, and clinical presentation, such as:

1.  Localized Tetanus: Symptoms remain confined to the muscles surrounding the wound or puncture site, and systemic symptoms such as fever or spasms in other body muscles are absent. For example, if a nail punctures the skin of the foot, the person may feel difficulty in walking and spasms or stiffness in muscles around the foot only.

2.  Generalized Tetanus: It is the most common and severe type, characterized by widespread muscle stiffness and spasms affecting different parts of the body, including lockjaw, neck, back, and limbs. It can also lead to life-threatening respiratory complications if left untreated.

3.  Neonatal Tetanus: It occurs in newborns due to the transfer of infection through the umbilical cord during deliveries conducted in unhygienic conditions. It can become a significant cause of infant mortality in regions with limited access to vaccination and healthcare facilities.

4.  Cephalic Tetanus: It is a rare form that occurs due to head trauma or ear infections and affects the cranial nerves, causing facial paralysis and difficulty in swallowing.

 

Diagnosis

There are no specific hospital or lab tests available for the diagnosis of tetanus. Hence, the diagnosis is purely based on signs and symptoms or the recent history of injury, cuts, or wounds of the patient.

 

Treatment

Treatment involves:

·  Killing of bacteria using certain antibiotics such as penicillin, metronidazole, or tetracycline (antibiotics may cause severe allergic reactions).

·    Anticonvulsants to relax the muscles and prevent spasms.

·    Muscle relaxants.

·    Those who feel difficulty in breathing may need ventilator support.

·  Tetanus immunoglobulins (TIG), containing antibodies can be injected into the bloodstream of the patient to neutralize the tetanus toxin.

 

Preventive Measures using Vaccination

·    Children should receive the five scheduled doses of vaccines within the first 6 years of age. The booster doses should be given every 10 years.

·    If infected, symptoms of tetanus may appear within 3 to 4 days; therefore, a dose of tetanus booster shot should be given within 48 hours of injury.

Tetanus Vaccine

Vaccine Composition

The vaccine contains the toxin of the tetanus-causing bacteria that has been weakened using certain procedures and is no longer toxic but can induce the formation of antibodies in the body. These antibodies fight the bacteria Clostridium tetani and destroy them. The vaccine should be given to pregnant women in the third trimester of pregnancy to protect the newborns.

The mild side effects of the vaccine include redness at the site of the injection, low fever, headache, fatigue, vomiting, diarrhea, and loss of appetite. Rarely, tetanus vaccination may cause severe allergic reactions, seizures, and high fever.