Tetanus: Causes and How It Spreads

For Everyone

Key points

  • Tetanus spores from the environment enter the body through cuts or wounds.
  • Tetanus doesn't spread from person to person.
  • It is possible to have tetanus infection more than once.
  • Prevent tetanus by staying up to date with vaccinations and seeking appropriate care after a wound.
Tetanus bacteria

Causes

Bacteria live in the environment

Spores of Clostridium tetani are common in the environment, including soil, dust, and manure. The spores develop into bacteria when they enter the body.

Common exposures

The spores can get into someone's body through broken skin, usually through injuries.

Tetanus bacteria are more likely to infect certain breaks in the skin, including:

  • Wounds contaminated with dirt, feces (poop), or saliva (spit)
  • Puncture wounds (wounds caused by an object, like a nail or needle)
  • Injuries with dead tissue (e.g., burns, crush injuries, frostbite)

Dead tissue is a concern because it can promote bacteria growth.

A construction worker uses a nail gun to build a house.
Puncture wounds are one way people are exposed to tetanus bacteria.

Other ways

Less common ways include breaks in the skin caused by

  • Chronic sores and infections
  • Dental infections
  • Insect bites
  • Intravenous (IV) drug use
  • Surgical procedures

How it doesn't spread

People don't spread tetanus bacteria to other people.

Reinfection is possible

Having a previous tetanus infection may not provide enough immunity to prevent reinfection. The best way to prevent tetanus infection is to be up to date with recommended tetanus vaccinations and seek appropriate care after a wound.

Keep Reading Tetanus Vaccination
Content Source
National Center for Immunization and Respiratory Diseases; Division of Bacterial Diseases
About This Page
Published: May 15, 2024
Updated: September 10, 2026

This page was last updated on this date. Updates may include minor edits, image changes, or other modifications to page content.

Reviewed: September 10, 2026

The information on this page was last reviewed by subject matter experts to ensure accuracy.