Tetanus: The Natural-Born Killer

Mia Battani and Kaleb Brooks

What is Tetanus, Exactly?

Tetanus, otherwise known as "lockjaw," is a bacterial infection, which usually enters the body through open wounds or pre-existing infections. This bacteria, scientifically referred to as Clostridium tetani, is naturally found in many common places, including ordinary soil on the ground. Despite this unnerving omnipresence, tetanus occurs rarely in modern times. Between 2000 and 2007, roughly 31 cases were reported annually. In the 1940s, however, the disease was much more prevalent. There were as many as 500-600 cases reported every year. But around that time, the vaccine became widely used and the number of infected people greatly improved. Luckily, Once the bacteria enters the body, anywhere from 3-21 days pass before any symptoms typically show up. The closer the injury is to the central nervous system, the shorter the incubation period is, and the shorter the incubation period, the smaller the chance of survival. The tetanus bacteria targets the nervous system, releasing the toxin tetanospasmin causing the trademark stiffness and spasms of muscles. One important thing to keep in mind is that the risk for getting tetanus is higher for anyone who works outdoors/in high-risk environments, is prone to injury, or uses injection drugs (including Insulin for diabetics). Finally, the antitoxin for tetanospasmin only works if the toxin has not yet bonded to nerve cells.

How does My Body Fight Off Tetanus?

There are many ways that the body attempts to fight off diseases such as tetanus. As many learn in high school biology class, the body's first line of defense is the skin; however, in the majority of tetanus cases, the skin is compromised before the bacteria enter the body. In this case, it is your body's inner immune system that plays a key role in fighting off the bacteria. The first defensive line is a group of contaminant-eating "guard cells" (called macrophages and neutrophils), whose main job is to recognize any foreign contaminant in the body's fluids and engulf it before it can infect cells and multiply. It is also at this stage where they signal for the cells that make up blood vessels to spread out and release fluids, causing what we know as inflammation.

Usually these two types cells alone can fight off diseases, but sometimes these defenses are overwhelmed and signal for a messenger to kick in the body's specific immune system responses, or cells that are specialized to attack specific pathogens in the body (not just any random foreign object). First of all, the messenger cell travels to the nearest lymph node to activate a type of cell called Helper-T cells, which multiply once activated. Most of these cells move to the infection site to fight off the infection in the body's fluids, but a second group remain behind to "remember" the bacteria in the case of a future infection of the same bacteria. Unfortunately, in the case of tetanus, memory cells aren't as helpful because the toxin released by the bacteria is so potent that it only needs a very small amount to do damage... an amount insufficient to make effective memory cells (and therefore acquired immunity) to tetanus. From there, a third group travels further into the lymph node to activate B-Cells, which have the ability to release antibodies to mark cells for death by macrophage. Helper-T Cells stimulate this process so that the B-Cell doesn't stop releasing these antibodies to get the maximum output possible. Again, this is a sort-of catch-22, because the tetanus bacteria attack nerve cells, which take months to replenish after being killed off. Simply stated, this is the reason why it takes so long to be completely over the tetanus disease. For a more detailed explanation of how the immune system works, please reference the video below.

The Immune System Explained I – Bacteria Infection

Symptoms, Treatment, and Prevention

The main symptoms of tetanus are stiffness in the neck, jaw, and abdominal muscles, difficulty swallowing, and painful spasms that can be caused by seemingly normal occurrences, such as a slight breeze or bright light. Other symptoms can include fever, sweating, rapid heart rate, and elevated blood pressure. Some spasms have been known to be severe enough to break necks, cause abnormal heart rhythms, and even cause death by impairing the ability to breathe.

Unfortunately, there is no end-all cure for tetanus. To diagnose tetanus, doctors solely use physical symptoms and behaviors, as lab tests are almost never useful for this bacteria. To treat tetanus, sedatives are often administered in heavy doses to help control muscle spasms, and an antitoxin can be administered, but does no good once the toxin has already bonded with nerve cells. Due to the slow division and repair rate of nerve cells, complete recovery may take months. The best course of action concerning tetanus is to stop it before it starts; in other words, receiving the tetanus vaccination is the best way to stop this disease before it can do any harm. Vaccination is especially important because in this case, the body cannot become naturally immune to tetanus due to the very small amount of toxin released to do damage. In order to remain immune to tetanus, it is recommended that after the initial vaccination series you get a booster shot every ten years. Because so little of the bacteria is needed to infect you, getting the disease and beating it once will not make you immune. You should also get a tetanus shot immediately after getting a wound that may contain the bacteria. The vaccination will jump start the immune system, just in case you get infected.

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