Tetanus (Lockjaw)

Tetanus is a condition that makes your muscles seize up and spasm uncontrollably. It happens when Clostridium tetani bacteria infect you. Once inside your body, the bacteria make a toxin that severely disrupts your nervous system, which can be life-threatening. Vaccination can prevent tetanus, which is why it’s rare in the U.S. and other developed nations.

Types of tetanus

There are four types of tetanus:

• Generalized. This is the most common. It causes severe muscle contractions, especially in your neck and jaw muscles.
• Neonatal. This form affects newborns within 28 days of birth. It’s rare in developed countries, but can be more common in developing countries or places with limited access to medical care.
• Localized. This form causes uncontrolled muscle spasms around the site where the bacteria entered your body. It isn’t common, but it can sometimes turn into generalized tetanus.
• Cephalic. This form is similar to the localized form, but it affects your cranial nerves. That means the symptoms mainly affect your head and face.

Symptoms of tetanus

Tetanus symptoms happen because the toxin disrupts your nervous system. Your muscles can spasm and relax when your nervous system tells them to. But the tetanus toxin disables nerve signaling that tells muscles to relax. That makes the affected muscles spasm uncontrollably.

The main symptoms include:

• Difficulty swallowing (dysphagia) or breathing (dyspnea)
• Drooling
• Face muscle flexing causing a rigid smile
• Inability to open your mouth because of jaw muscle tightness (trismus)
• Muscle spasms in your abs, back, arms or legs (which light and sound can trigger)
• Overextending your neck and back because of muscle spasms (opisthotonos)
• Seizures

Tetanus can also affect your autonomic nervous system. That’s the part that controls automatic functions like breathing and heart rate. Autonomic symptoms usually take several days before they start. When they do, they can include the following:

• Fever and sweating
• High blood pressure
• Fast heart rate (tachycardia)
• Uncontrolled peeing (urinary incontinence) and pooping (fecal incontinence)

Tetanus causes

Tetanus happens because of a toxin that C. tetani bacteria make. That’s why tetanus doesn’t spread person-to-person.

Tetanus-causing germs can enter a wound in either a spore or bacilli (active bacteria) form. The spore form is harder to kill, and it can survive boiling water. The spores live in soil, especially soil with manure mixed in. It’s easier for this bacteria to get into deeper cuts and punctures. And tetanus with deeper wounds is often more severe.

Some ways you can get this bacteria in a wound include:

• Broken bones that break through your skin (compound fractures)
• Burns
• Crush injuries that break skin
• Dental infections
• Insect bites and dog bites that get contaminated
• Surgical wounds
• Using contaminated needles or medical instruments
• Minor injuries that can happen around the house, like cuts and scrapes or stepping on a nail

While wounds are the usual entry point, many people don’t remember getting the wound that caused tetanus for them. Research shows that up to half of all cases don’t have an identifiable wound or infection site that experts can pinpoint.

Tetanus risk factors

The main risk factors for tetanus are:

• Age. Adults over 65 are less likely to have protection from tetanus vaccination. The vaccination’s protection weakens over time. And many people over 65 were born before childhood tetanus vaccination became widespread.
• Incomplete vaccination. The tetanus vaccine comes in a series. Without all of them, you don’t have the vaccine’s full protection.
• Diabetes. From 2013 to 2022, people with diabetes accounted for about 1 in 10 cases of tetanus in the U.S. And they accounted for nearly 1 in 6 tetanus-related deaths.
• Immune suppression. It’s easier for tetanus-causing bacteria to infect people with a weakened immune system.
• Injectable drug use. Just under 1 in 10 U.S. tetanus cases between 2012 and 2022 happened in people who inject drugs.

Neonatal tetanus causes and risk factors

Neonatal tetanus usually happens because of an infection that affects a newborn whose mother wasn’t immune. Without that immunity, a newborn is vulnerable to the infection through any wound. And the usual wound they get it from is from the stump of their umbilical cord.

The main risk factors for neonatal tetanus include:

• An unvaccinated or partially vaccinated mother
• Umbilical cord wound contamination from unsterilized tools used to cut the cord, improper cord handling, etc.

Complications of tetanus

Tetanus can cause a number of complications. Some are because of the muscle spasms that this disease causes. Others are because of disruptions in your autonomic nervous system. The complications can include, but aren’t limited to, the following:

• Airway muscle spasms that block breathing
• Blood clots
• Kidney failure
• Sepsis
• Death

How doctors diagnose tetanus

There aren’t any laboratory tests to diagnose or confirm tetanus. Your healthcare provider will diagnose tetanus based on your symptoms. They’ll perform a physical examination and ask you about your medical history.

Your provider may also use the “spatula test.” To do that, they’ll use a soft instrument or spatula to touch the back of your throat inside your mouth. Ordinarily, that triggers your gag reflex and makes you want to spit the spatula out. But if you have tetanus, it’ll trigger muscle spasms that make you clench your jaw.

How is tetanus treated?

If your healthcare provider suspects you have tetanus, they’ll start treating it immediately. That treatment involves the following:

• Wound care. Cleaning (debriding) your wound can remove some of the bacteria, stopping them from releasing more toxins. This can shorten how long the effects of tetanus last.
• Medications. Tetanus antitoxin will block additional toxin from taking effect. Antibiotics like metronidazole may help get rid of remaining bacteria. You’ll also likely receive muscle relaxers, benzodiazepines or other drugs to treat tetanus symptoms.
• Rest. Light and sound can trigger tetanus muscle spasms. Your provider will likely recommend you rest in a dim, quiet room to limit spasms.
• Breathing support. Keeping your airway open is a top priority. If you need breathing tube placement and mechanical ventilation, you’ll likely receive sedation to help keep you comfortable.

Recovery time

Once tetanus symptoms develop, it can take two to three weeks for the disease to run its course. But it can take months to recover from tetanus. Your healthcare provider can tell you more about what’s likely to happen in your specific case.

Can this be prevented?

Tetanus is extremely preventable with vaccination. In the U.S., vaccination starts during infancy. Children typically receive the tetanus vaccine as part of their childhood immunization schedule.

Having tetanus once before doesn’t make you immune to it. Vaccination is the only way to get that immunity. And the immunity wears off over time, so you need a booster about every 10 years. That’s one reason why older adults have a higher risk of developing tetanus.

Even if your vaccination is out of date, tetanus vaccination can save your life. People who receive at least three doses of the tetanus vaccine almost always survive this disease. And even partial vaccination can make your case less severe.

In general, you need a booster shot for tetanus if you have a new deep or potentially contaminated wound and any of the following apply to you:

• You received fewer than three shots from the tetanus vaccine series
• Your vaccination status is unknown
• Your last booster was 10 or more years ago

What can I expect if I have tetanus?

Tetanus is a severe, life-threatening condition. But with proper treatment, most people recover. Most people develop symptoms about a week after the bacteria get into their body. But it can happen as quickly as two days or as long as three weeks after.

The muscle spasms from tetanus will start around where they entered your body. You’ll then develop muscle spasms in the muscles around your eyes and trouble opening your jaw. The spasms can be painful and typically spread downward to your neck and back.

Your healthcare team will prioritize keeping your airway open using intubation. Once that’s done, they’ll start treating your other symptoms. That includes making you as comfortable as possible with medications to dampen muscle spasms and manage any pain you have.

Tetanus can vary depending on many factors. Your healthcare provider can tell you more about what you’re likely to experience. They can also guide you on what you can do to help yourself as you recover. But in general, with proper treatment, the odds of survival with tetanus are good.

Does rust cause tetanus?

Rust doesn’t cause tetanus. The rust itself is a sign that an object probably carries germs, including the one that causes tetanus.