A tetanus shot generally provides protection for about 10 years. Adults are recommended to receive a tetanus booster every 10 years to maintain immunity, as the vaccine's protective effects decrease over time

. For children, the initial series includes multiple doses starting in infancy, with a booster (Tdap) given around age 11 or 12. After that, adults should continue with Td or Tdap boosters every decade

. There is some research suggesting that immunity may last longer—up to 30 years after the full childhood series—but current official guidelines still recommend boosters every 10 years for adults

. In case of a deep or contaminated wound, a tetanus booster may be recommended regardless of when the last shot was given, to ensure immediate protection

. Summary:

• Initial childhood series plus adolescent booster
• Adult booster every 10 years generally recommended
• Some evidence suggests immunity could last up to 30 years, but not yet standard practice
• Booster recommended sooner if at risk due to injury

This schedule helps maintain effective protection against tetanus infection, which can be severe and life-threatening without vaccination