Tetanus: When You Need a Booster After a Cut, Rusty Nail or Animal Bite

Tetanus is a serious infection caused by bacteria found in soil, dust and animal faeces. It produces a toxin that causes painful muscle spasms, lockjaw and breathing problems. It is not spread from person to person, and it is preventable with vaccination. The World Health Organization reports that it remains a cause of death in parts of the world with low vaccination coverage, including newborns.

He steps on a nail in the garden and almost ignores it. Instead, he checks his vaccination record, cleans the wound and gets a booster that afternoon. Tetanus is rare, and that is why.

Which wounds carry a higher risk?

• Puncture wounds, such as from nails or thorns
• Wounds contaminated with soil, dust or manure
• Animal bites
• Burns and crush injuries
• Wounds with dead tissue or a foreign body
• Wounds not cleaned or treated for more than 6 hours

Do I need a booster?

It depends on how many doses you have had and how dirty the wound is. In general:

• Fully vaccinated (usually 5 doses in the UK, or a primary course plus boosters): often no booster needed for clean wounds, but a health professional will assess higher-risk wounds
• Not fully vaccinated or unsure: you will usually be offered a tetanus-containing vaccine, and for high-risk wounds, tetanus immunoglobulin as well
• Schedules differ by country; for example, the US recommends a booster every 10 years, or after 5 years for a dirty wound

Wound care

1. Wash the wound thoroughly with clean running water
2. Remove dirt and debris
3. Cover with a clean dressing
4. Seek care for deep, dirty or large wounds, bites, or wounds that will not stop bleeding

“But it is only dangerous if the nail is rusty.”

Rust does not cause tetanus. The bacteria live in soil, dust and manure, so any wound contaminated with dirt can carry a risk, rusty or not.

Related: Dog bites and rabies

Sources: World Health Organization tetanus fact sheet; UK Health Security Agency, Green Book chapter on tetanus; US Centers for Disease Control and Prevention tetanus vaccination guidance.