Tetanus

Tetanus is a serious bacterial infection that attacks the nervous system, causing painful muscle spasms throughout the body. While it can be life-threatening, vaccination offers highly effective protection, making this once-common disease now rare in countries with strong immunization programs.

Table of contents

• What is tetanus
• How tetanus spreads and enters the body
• Signs and symptoms
• Different forms of tetanus
• Who is at risk
• Possible complications
• How tetanus is diagnosed
• Treatment and care
• Prevention through vaccination
• Recovery and outlook

What is tetanus

Tetanus is a serious disease of the nervous system caused by bacteria called Clostridium tetani (C. tetani). These bacteria produce a powerful poison, called a toxin, that severely disrupts how your nerves and muscles work.^[1] The disease causes muscle contractions and spasms, particularly affecting the jaw and neck muscles.^[1]

Tetanus is commonly known as “lockjaw” because it typically causes spasms of the jaw muscles, making it difficult or impossible to open the mouth.^[3] The name comes from the Ancient Greek word meaning “tension, stretched, rigid.”^[7]

Because of widespread vaccination programs, cases of tetanus are now rare in the United States and other developed countries.^[1] However, the disease remains a significant public health problem in many parts of the world, especially in low-income countries where immunization coverage is low.^[2] Worldwide, tetanus caused an estimated 34,700 deaths in 2019, mostly in South Asia and Sub-Saharan Africa.^[16]

How tetanus spreads and enters the body

Tetanus cannot be spread from person to person.^[2] The only way to get tetanus is when C. tetani bacteria enter your body through a break in the skin.^[5]

The tetanus bacteria exist as tiny, hardy cells called spores that are found everywhere in the environment.^[2] They are particularly common in soil, dust, ash, animal feces and manure, and on the surfaces of rusty tools like nails, needles, and barbed wire.^[2] These spores are extremely resistant to heat and most cleaning products, and they can survive in soil for many years.^[2]

The bacteria generally enter through a break in the skin, such as a cut or puncture wound caused by a contaminated object.^[1] Common ways people can get tetanus bacteria into a wound include:

• Stepping on rusty nails or other sharp objects^[3]
• Cuts or wounds contaminated with dirt, soil, feces, or saliva^[3]
• Puncture wounds that are deep^[3]
• Broken bones that break through the skin^[6]
• Burns and crush injuries that break the skin^[6]
• Animal bites and insect bites that get contaminated^[3]
• Dental infections^[6]
• Surgical wounds^[6]
• Using contaminated needles or medical instruments^[6]
• Minor injuries around the house, like cuts and scrapes^[5]

It is easier for the bacteria to get into deeper cuts and punctures, and tetanus with deeper wounds is often more severe.^[6] However, many people who develop tetanus don’t remember getting the wound that caused it. Research shows that up to half of all cases don’t have an identifiable wound that experts can pinpoint.^[6]

In developing countries, neonatal tetanus occurs when nonsterile instruments are used to cut the umbilical cord or when contaminated material is used to cover the umbilical stump during delivery.^[2]

Signs and symptoms

The time between when the bacteria enter your body and when symptoms appear is called the incubation period. For tetanus, this period varies between 3 and 21 days after infection, with most cases occurring within 14 days.^[2] On average, symptoms appear about 7 to 10 days after infection.^[1]

The most common first sign is spasms of the jaw muscles, known as “lockjaw” or trismus.^[3] Other symptoms of tetanus include:

• Painful muscle spasms and stiff, immovable muscles in the jaw^[1]
• Difficulty swallowing^[1]
• Tension of muscles around the lips, sometimes producing a persistent grin or grimace (called risus sardonicus)^[1]
• Painful spasms and rigidity in the neck muscles^[1]
• Stiffness in the shoulders, back, and other muscles^[5]
• Rigid abdominal muscles^[1]
• Drooling^[6]
• Muscle spasms in the arms and legs^[6]
• Seizures^[3]
• Headache^[3]
• Fever and sweating^[3]
• Changes in blood pressure and fast heart rate^[3]

As the disease progresses, repeated painful spasms occur that last for several minutes. These severe spasms may be triggered by minor events that stimulate the senses, such as a loud sound, a physical touch, a draft, or light.^[1] During these episodes, the neck and back may arch backward, the legs become rigid, the arms are drawn up to the body, and the fists are clenched.^[1] This arching of the back is called opisthotonos.^[6]

Patients remain fully conscious during spasms and feel severe pain.^[8] The muscle rigidity in the neck and abdomen may cause breathing difficulties.^[1]

Different forms of tetanus

There are four main types of tetanus:^[6]

Generalized tetanus is the most common form. It causes severe muscle contractions, especially in the neck and jaw muscles, that spread throughout the body.^[6] Approximately 50 to 75 percent of patients with generalized tetanus first present with trismus (lockjaw).^[8]

Neonatal tetanus, also called tetanus neonatorum, affects newborn babies within 28 days of birth.^[6] It is rare in developed countries but can be more common in developing countries or places with limited access to medical care.^[6] This form results from umbilical cord contamination during unsanitary delivery, coupled with a lack of maternal immunization.^[8] In 2018, approximately 25,000 newborns died from neonatal tetanus, a 97 percent reduction from 1988.^[2]

Localized tetanus causes uncontrolled muscle spasms around the site where the bacteria entered the body.^[6] It is not common, but it can sometimes turn into generalized tetanus.^[6] The muscular rigidity is caused by a dysfunction in nerve signals that control the affected muscles.^[8]

Cephalic tetanus is similar to localized tetanus but affects the nerves that control the head and face, called cranial nerves.^[6] This uncommon form usually occurs after head trauma or ear infection.^[8]

Who is at risk

Anyone can get tetanus.^[3] However, several factors can increase the risk of tetanus infection.

People who have never received a tetanus vaccine are at increased risk.^[3] Similarly, people who didn’t complete the primary vaccination series or who aren’t up to date with their 10-year tetanus booster shots are also at increased risk.^[3]

People with a recent wound are at increased risk for tetanus, especially if the wound is deep or contaminated with dirt.^[3] The most susceptible wounds are those that are grossly contaminated or caused by blunt trauma or bites.^[13]

Other risk factors associated with an increased risk of tetanus include:^[3]

• Being 80 years or older
• Having diabetes
• Having an immunocompromising condition
• Using injection drugs

Tetanus primarily affects older adults because of their higher rate of being unvaccinated or inadequately vaccinated.^[8] In the United States, immunity levels tend to be lower in older age groups.^[16]

The disease is particularly common and serious in newborn babies and pregnant women who have not been sufficiently immunized with tetanus vaccines.^[2] There is also increased risk of tetanus in adolescent and adult males who undergo circumcision due to waning immunity and limited opportunity for receiving booster doses.^[2]

Possible complications

Tetanus can cause serious health problems and can be life-threatening.^[3] Severe complications of tetanus include:

• Laryngospasm (uncontrolled tightening of the vocal cords)^[3]
• Broken bones (fractures)^[3]
• Pulmonary embolism (blockage in the lungs caused by a blood clot)^[3]
• Aspiration pneumonia (lung infection from inhaling spit or vomit)^[3]
• Breathing difficulty^[3]
• Spasm of the vocal cords^[5]
• High blood pressure^[5]
• Lung clots^[5]

Spasms can be severe enough to fracture bones or cause tendons to rupture.^[8] The spasms can also cause acute respiratory failure.^[8]

If the effect of the toxin on respiratory muscles interferes with breathing, a person may die of suffocation.^[20] Tetanus can lead to death, with about 1 in 10 cases in the United States being fatal.^[3] Approximately 11 percent of reported cases of tetanus are fatal, with deaths more likely to occur in persons 60 years of age and older.^[5]

How tetanus is diagnosed

Healthcare providers usually decide if someone has tetanus by looking for common signs and symptoms.^[3] Doctors diagnose tetanus based on a physical exam, medical and vaccination history, and the signs and symptoms of muscle spasms, muscle rigidity, and pain.^[10]

They may also ask about a recent history of cuts, scrapes, punctures, and trauma.^[3] There is no laboratory test that can confirm tetanus.^[3] Symptoms usually confirm the diagnosis, and no lab or other kinds of tests are available.^[5]

Treatment and care

Tetanus is a medical emergency that requires immediate treatment in a hospital.^[3] A tetanus infection requires emergency and long-term supportive care while the disease runs its course, often in an intensive care unit.^[10]

Treatment focuses on managing symptoms and complications until the effects of the tetanus toxin resolve.^[1] There is no cure for tetanus.^[1] The goals of treatment include:

• Initiating supportive therapy^[13]
• Cleaning and caring for wounds^[13]
• Stopping the production of toxin within the wound^[13]
• Neutralizing unbound toxin^[13]
• Controlling disease symptoms^[13]
• Managing complications^[13]

Wound care requires cleaning to remove dirt, debris, or foreign objects that may be harboring bacteria.^[10] Healthcare teams will also clear the wound of any dead tissue that could provide an environment in which bacteria can grow.^[10] All wounds should be explored, carefully cleansed, and properly cleaned.^[13]

Medications used in treatment include:

Tetanus immune globulin (TIG) is given to remove unbound tetanus toxin from the body.^[11] It can’t affect toxin already bound to nerve endings.^[11] Medical experts recommend a single 500 international unit dose of TIG for tetanus treatment.^[11] If TIG is not available, healthcare providers can use immune globulin intravenous (IGIV).^[11]

Antibiotics, given either orally or by injection, may help fight tetanus bacteria and reduce the number of bacteria in the wound.^[10] Metronidazole is the preferred antibiotic.^[13]

Sedatives and muscle relaxants that slow the function of the nervous system can help control muscle spasms.^[10] Healthcare providers should use these drugs as needed to control muscle spasms.^[11]

Tetanus vaccination helps the immune system fight the toxins.^[10] Vaccination is recommended during recovery because tetanus disease doesn’t result in tetanus immunity.^[11]

Other medications might be used to regulate involuntary muscle activity, such as heartbeat and breathing.^[10] Patients may also require medicines to control autonomic nervous system instability.^[11]

Supportive care includes treatments to make sure the airway is clear and to provide breathing assistance.^[10] Healthcare providers should monitor for airway patency because associated muscle spasms can cause airway loss.^[11] Depending on disease severity, endotracheal intubation or tracheostomy and mechanically assisted respiration may be lifesaving.^[11] A feeding tube into the stomach is used to provide nutrition.^[10]

Patients are usually kept in dark and quiet environments to prevent reflex spasms.^[13]

Prevention through vaccination

Vaccination is the best way to prevent tetanus.^[3] Tetanus can be prevented through immunization with vaccines containing tetanus toxoid.^[2] The tetanus vaccine is safe and effective, and the vaccine series, including booster doses, is nearly 100 percent effective in preventing tetanus.^[22]

There are three kinds of vaccines used in the United States today to protect against tetanus. They also protect against diphtheria and whooping cough (pertussis):^[22]

• DTaP (diphtheria, tetanus, and pertussis) vaccines for infants and children up to age 7
• Tdap (tetanus, diphtheria, and pertussis) vaccines for adolescents, teens, adults, and pregnant people
• Td (tetanus and diphtheria) vaccines for adults

For children, the vaccination schedule includes:^[5]

• Five doses of DTaP vaccine before age 7, usually given at 2 months, 4 months, 6 months, 15 to 18 months, and 4 to 6 years of age
• One dose of Tdap between 11 and 12 years of age

For adults, a Td vaccine booster should be received every 10 years.^[5] A Tdap booster is also recommended during the third trimester of pregnancy.^[22]

Nearly all cases of tetanus today are in people who never got a tetanus vaccine or did not receive a complete course of tetanus vaccines, or adults who didn’t stay up to date on their 10-year booster shots.^[22]

Wound care is also important for prevention. Immediate and good wound care can help prevent infection:^[3]

• Apply first aid to even minor, non-infected wounds
• Wash hands with soap and water or use an alcohol-based hand rub
• Consult a healthcare provider if wounds are from a puncture, are deep, contain dirt or dead tissue, or are from an animal bite

For people with wounds who aren’t up to date with tetanus vaccination, healthcare providers may use medicine called human tetanus immune globulin (TIG) to help prevent tetanus.^[3] Vaccination also helps prevent tetanus in people with wounds, depending on their tetanus vaccination history.^[3]

Recovery and outlook

Complete recovery from tetanus can take several months.^[11] The disease progresses for about two weeks, and recovery can last about a month.^[10] Severe muscle spasms may last for about three to four weeks and then slowly get better.^[20] Once these spasms subside, recovery takes several months.^[20]

Most healthy children and adults recover from tetanus, though the disease causes a serious prolonged illness.^[5] The recovery from tetanus may take months, and about 10 percent of cases prove to be fatal.^[7]

People who recover from tetanus do not have natural immunity and can be infected again.^[2] Tetanus disease doesn’t result in tetanus immunity, so vaccination is recommended as soon as the patient’s condition has stabilized.^[11]