What is Tetanus?
Tetanus (sometimes also referred to as lockjaw) is a serious and potentially life-threatening bacterial infection caused by the toxin of the bacterium Clostridium tetani. This bacterium is found in soil, dust and animal faeces. The infection affects the nervous system, specifically the motor neurons, causing muscle stiffness and spasms [1, 2].
The infection itself commonly occurs with deep puncture wounds which occur in a dirty environment - stepping on a rusty nail is one of the most commonly cited routes of entry.
Symptoms of Tetanus
The most common symptoms of tetanus include:
- painful spasms in the stomach,
- muscle contractions or spasms in the neck and jaw,
- difficulty swallowing,
- muscle stiffness, and
- difficulty breathing.
Other symptoms can include seizures, severe headaches, fever, elevated blood pressure or tachycardia (elevated heart rate).
Severe cases may experience:
- tightening of the vocal chords and inability to speak,
- convulsions and severe spasms (sometimes to an extent of broken bones as a result),
- pulmonary embolisms,
- pneumonia,
- muscle spasms in the chest resulting in a complete inability to breathe - this can be fatal [3].
Outcomes of Tetanus
Without treatment, tetanus can be fatal. According to the Centre for Disease Control and Prevention (CDC), between 10 and 20% of all tetanus infections result in death. However, with prompt diagnosis and adequate treatment, most patients experience full recovery with no long-term impairments.
However, in severe cases, patients can require several weeks of hospitalisation and intensive treatment, which can lead to secondary problems such as hospital-acquired infections [2, 4].
Treatment for Tetanus
The treatment for tetanus is designed to control the muscle spasms and reduce cardiovascular instability (control the blood pressure and heart rate). Consequently, this consists of:
- wound debridement (cleaning the wound and removing all dirt and potentially dead tissue),
- administration of antitoxin - this is an antibody that neutralises the bacterial toxin,
- administration of antibiotics,
- supportive care.
Recent research in tetanus treatment has focused on intravenous administration of magnesium sulphate to control the muscle spasms, and administration of antitoxin to the cerebrospinal fluid as a more effective means of delivery.
In severe cases, the patients may require mechanical ventilation as a supportive measure.
Prevention is arguably most important in tetanus treatment - the disease can be prevented by vaccination (such as the TDAP vaccine or other tetanal toxoid vaccines), and the odds of contracting tetanus can be lowered by appropriate wound care [2, 5].
Causes of Tetanus
Tetanus is caused by the bacterium Clostridium tetani. In the environment, the bacterium produces spores as a means of reproduction - these are found in manure, soil and dust. Infection occurs via deep cuts or wounds, such as burns or injuries caused by nails [6].
The highest odds of contracting tetanus are from puncture wounds which are narrow and deep, because they don't allow for oxygen to access - oxygen is toxic to the spores of the bacteria [7]. Cleaning every wound thoroughly is important to prevent tetanus [7].
Does Rust Cause Tetanus?
Stepping on a rusty nail is arguably the most common means of getting tetanus. However, rust itself does not cause tetanus.
Tetanus is contracted from wounds inflicted by rusty nails due to the fact that rusty nails cause deep puncture wounds and are found in the same environment as the tetanus-causing bacteria such as sheds, fields or abandoned houses. Also, the rusting metal can provide an environment for the tetanus spores to accumulate [8].
Odds from getting tetanus from rusty nails
The literature does not provide a conclusive answer on how likely a person is to contract tetanus from a wound inflicted by a rusty nail or a scratch. While you definitely can get tetanus through a wound inflicted by a rusty nail or through a scratch, there are multiple factors that influence the probability of contracting tetanus:
- Vaccination status - getting vaccinated is the best protection against contracting tetanus. Multiple vaccines are available - consult with your doctor which option is the best for you. If you haven't had a tetanus booster shot in the past 5 years or can't remember when you had your last one, you should see your doctor for a tetanus booster [9].
- Prompt intervention - You should seek medical care immediately if you believe you got scratched by a rusty object or have a deep wound. It is important to get the wound properly cleaned to minimise the chance of getting tetanus.
- Environment - Tetanus infection is more likely to occur in a dirty environment, as the Clostridium tetani spores survive in soil, dirt, dust and manure.
- Wound care - if the wound is not cleaned properly, chances are that some tissue will become necrotic (dead). As the tetanus bacteria thrive in necrotic tissue, this will increase the chance of contracting tetanus. Wounds should be cleaned and disinfected thoroughly very promptly.
Summary: Can you get tetanus from a scratch?
Tetanus infection occurs through exposure to the bacterium Clostridium tetani in a dirty environment through an open wound. It is therefore possible to get tetanus from a scratch.
It is important to get vaccinated against tetanus to lower the chance of contracting it, as well as clean every wound thoroughly or seek medical care promptly.