Clinical Overview of Tetanus

Key points

  • Clostridium tetani (C. tetani) bacteria produce potent toxins and can cause tetanus.
  • C. tetani are common in the environment and infect people through breaks in the skin.
  • Not being up to date with tetanus vaccines is the biggest risk factor for infection.
Clostridium tetani bacteria cause tetanus.


Tetanus is an infection caused by C. tetani spores. In anaerobic conditions, including those within the body, the spores germinate.

The bacteria produce very potent toxins that the blood stream and lymphatic system can disseminate throughout the body. One of these toxins, tetanospasmin (tetanus toxin), is responsible for the serious effects of tetanus.

Tetanus toxin acts in the sympathetic nervous system and at several sites within the central nervous system:

  • Brain
  • Peripheral motor end plates
  • Spinal cord

Tetanus toxin causes the typical clinical manifestations of tetanus by interfering with the release of neurotransmitters and blocking inhibitor impulses. This leads to unopposed muscle contraction and spasm.


There are three clinical forms of tetanus: generalized (includes neonatal tetanus), localized, and cephalic. They present with different signs and symptoms.

Keep Reading: Clinical Features

Risk factors

Nearly all U.S. tetanus cases today are among adults who either

  • Never received a tetanus vaccine
  • Didn't stay up to date with their 10-year tetanus booster shots

Other risk factors for tetanus include:

  • Being 70 years or older
  • Having diabetes
  • Immunosuppression
  • Using intravenous drugs

Disasters such as earthquakes, hurricanes, floods, and tsunamis generally don't raise the level of tetanus in the environment.

However, the number of tetanus cases may increase during natural disasters because of injuries leading to tetanus exposure. There may also be delays in or lack of medical services and supplies.

Incubation period

The incubation period ranges from 3 to 21 days, averaging about 8 days.

In general, the further the injury site is from the central nervous system, the longer the incubation period. A shorter incubation period is associated with

  • More severe disease
  • Higher chance of death

Neonatal tetanus

Symptoms usually appear from 4 to 14 days after birth, averaging about 7 days.

The incubation period is short, usually 1 to 2 days.

How it spreads

C. tetani spores live in the environment. They usually enter the body through a wound or break in the skin.

Neonatal tetanus usually occurs when C. tetani enters the body after an umbilical stump infection.

Risk of death

Even with modern intensive care, generalized tetanus results in death for about 1 in 10 cases.

The risk of death from tetanus is highest among people 70 years of age or older.


Wound management is a key strategy to prevent tetanus.

In addition, CDC recommends everyone stay up to date with their recommended tetanus vaccinations to prevent tetanus.

Diagnosis and treatment

Tetanus is a clinical syndrome without confirmatory laboratory tests. People with tetanus require emergency medical care.

Surveillance and trends

Tetanus is an uncommon but reportable condition in the United States.