What Is Tetanus? Key Facts Every Biology Student Should Know
What is Tetanus?
Tetanus is a severe bacterial infection that attacks the nervous system and causes muscles in the body to tighten. Tetanus is also known as lockjaw as the infection usually causes muscle contraction in the neck and jaw, after which it spreads to other parts of the body. It is a life-threatening infection without treatment. It is a medical emergency that requires urgent treatment in the hospital.
Fortunately, using vaccines, we can prevent the spread of tetanus infection. The vaccine does not last forever, and booster shots are required every ten years to strengthen the immunity against the tetanus bacteria. Tetanus is a rare disease in countries that have adequate vaccination.
Clostridium Tetani Bacteria
[Image will be Uploaded Soon]
Tetanus Causes
Bacteria, named Clostridium Tetani, is the leading cause for tetanus. The bacteria is commonly found in contaminated soil, and animal manure, but may tend to exist anywhere. When this bacterium enters the body, it rapidly multiplies and releases tetanospasmin, a neurotoxin. Tetanus symptoms are caused in the whole body when tetanospasmin enters the bloodstream and spreads. It interferes with the signals that travel from the brain to the nerves in the spinal cord. And from there to the muscles causing muscle spasm and stiffness.
The bacteria Clostridium Tetani enters the body through cuts in the skin or puncture wounds. Cleaning thoroughly on the injury can prevent the bacteria from entering and thereby developing an infection.
Some of the Common Ways by Which Tetanus Can Enter are:
Crush injuries
Puncture wounds
Wounds containing dead tissues
Burns
Some of the Rare but Possible Ways by Which you Can Contract Tetanus are:
Insect bites
Injections into muscles
Surgical procedures
Intravenous drug use
Dental infections
Superficial wounds
Compound fractures
Symptoms of Tetanus
Usually, after 7 to 10 days after contracting the infection, symptoms start appearing. However, it can vary from 4 days to 3 weeks and may also take months in some cases. The incubation period is more extended when the site of injury is further from the central nervous system.
Symptoms in muscles include stiffness and spasm. Usually, the stiffness starts with the chewing of muscles; hence it has got the name lockjaw. Further muscle spasm spreads to the throat and neck, causing the inability to swallow. Often patients have a seizure in the facial muscle. Difficulties in breathing may result in stiffness of chest and neck muscles. In some cases, limb and abdominal muscles are also affected.
In some severe cases, the spine arch backward as the muscles are affected. This symptom is more common in children affected by tetanus infection.
Here are some of the other symptoms an individual may get
Diarrhoea
Headache
Bloody stools
Touch sensitivity
Fever
Sore throat
Sweating
Increased heartbeat
Treatment
It is imperative to clean the cut thoroughly to prevent infection. Only a medical practitioner should attend to a tetanus-prone wound immediately.
A wound that can likely develop tetanus is stated as:
A burn or wound that needs surgical intervention and is delayed for over 6 hours.
A sore that has a large amount of tissue removed
Puncture injury that has encounters soil or manure
Compound fractures where the bone is exposed to infection
Burns or wounds in patients with systemic sepsis
Any patient that contracts a type of wound mentioned above must immediately receive tetanus immunoglobulin (TIG) even if they are vaccinated before. TIG contains antibodies that kill the bacteria Clostridium Tetani. The vaccination is given into the veins, which provides quick short-term protection against tetanus. It does not replace the long-term effects of the injection. TIG can be safely supplied to the expectant and breastfeeding mothers.
For the treatment of tetanus, doctors may prescribe metronidazole or penicillin. Patients allergic to these medicines are prescribed tetracycline. The antibodies prevent the bacteria from multiplying in the body and producing neurotoxin.
For the treatment of muscle stiffness and spasm patients may be given:
Anticonvulsants
Muscle relaxants
Neuromuscular blocking agents
Surgery
If the wound prone to tetanus is large, doctors may surgically remove the infected and damaged muscle through debridement. It is an act of removing contaminated and dead tissue.
Nutrition
Due to increased muscle activity, a tetanus patient may require a high intake of calories daily.
Ventilator
Ventilator support may be required for some patients to help them breathe if the respiratory muscles and vocal cords are affected.
FAQs on Tetanus: Causes, Symptoms, and Prevention
1. What is tetanus and which microorganism causes it?
Tetanus, commonly known as lockjaw, is a serious bacterial infection that affects the nervous system, leading to painful muscle contractions, particularly of the jaw and neck muscles. The disease is caused by the spores of the bacterium Clostridium tetani, which are commonly found in soil, dust, and animal manure.
2. How does the Clostridium tetani bacterium cause infection in the human body?
The infection begins when the spores of Clostridium tetani enter the body through a deep cut, puncture wound, or burn. In the low-oxygen (anaerobic) environment of the deep tissue, these spores germinate into active bacteria. The bacteria then multiply and produce a potent neurotoxin called tetanospasmin, which travels through the bloodstream and lymphatic system to affect the central nervous system.
3. What are the most common symptoms of tetanus?
The symptoms of tetanus are caused by the neurotoxin affecting motor neurons. Common signs include:
- Spasms and stiffness in the jaw muscles, a condition known as lockjaw or trismus.
- Stiffness of the neck, chest, and abdominal muscles.
- Painful body spasms, often triggered by minor stimuli like a loud noise or light touch.
- Difficulty swallowing (dysphagia).
- Fever, sweating, and rapid heart rate.
4. How is tetanus prevented, especially after an injury?
The primary method of prevention is vaccination. The tetanus toxoid vaccine (often given as part of DTaP, Tdap, or Td) stimulates the body to produce antibodies. A booster shot is recommended every 10 years. For an unimmunized or insufficiently immunized person with a tetanus-prone wound, immediate medical care is crucial, which may include a dose of the tetanus vaccine and Tetanus Immune Globulin (TIG) to provide immediate passive immunity.
5. What is the typical incubation period for tetanus?
The incubation period for tetanus—the time from exposure to the bacteria to the onset of symptoms—can range from 3 to 21 days, with an average of about 10 days. A shorter incubation period is often associated with a more contaminated wound and a more severe form of the disease.
6. Is it a myth that only rusty objects cause tetanus?
Yes, this is a common misconception. Rust itself does not cause tetanus. The real cause is the Clostridium tetani bacterium. Rusty objects, like nails, are often found outdoors in soil or environments where these bacteria thrive. The rough surface of a rusty object can create a deep puncture wound, which provides the ideal anaerobic (low-oxygen) conditions for the bacterial spores to germinate. However, any wound from a clean nail, splinter, or even an animal bite can cause tetanus if contaminated with the bacteria.
7. How exactly does the tetanus toxin lead to muscle spasms and lockjaw?
The tetanus toxin, tetanospasmin, travels to the central nervous system where it selectively targets and blocks the release of inhibitory neurotransmitters, namely GABA and glycine, from nerve endings. These neurotransmitters are essential for relaxing muscles after they contract. By blocking their release, the toxin causes motor neurons to become overactive, leading to a state of constant contraction, which manifests as the characteristic muscle stiffness and severe spasms seen in tetanus.
8. Can a person who recovers from a tetanus infection get it again?
Yes, recovering from a tetanus infection does not provide natural immunity against future infections. This is a unique aspect of the disease. The amount of tetanospasmin toxin required to cause severe illness is so minuscule that it is insufficient to trigger a protective memory immune response. Therefore, even after surviving tetanus, a person must be fully vaccinated to be protected in the future.
9. What is the difference between tetanus and tetany?
While their names sound similar and both involve muscle spasms, they are fundamentally different. Tetanus is an infectious disease caused by the neurotoxin from the Clostridium tetani bacterium. In contrast, tetany is a medical sign or symptom, not a disease itself. Tetany refers to involuntary muscle cramps and spasms caused by metabolic imbalances, most often significantly low levels of calcium in the blood (hypocalcemia) or other electrolyte disturbances.
10. Why is a tetanus booster shot necessary every 10 years?
The immunity conferred by the tetanus vaccine is not lifelong. Over time, the level of protective antibodies against the tetanus toxin in the body gradually decreases. A booster shot serves to 'remind' the immune system, stimulating it to produce a new surge of antibodies and reinforcing its memory. Maintaining this high level of antibodies is crucial for immediately neutralizing any tetanus toxin that may enter the body after an injury, thereby preventing the disease. The 10-year interval is based on clinical studies showing how long protective immunity typically lasts.
