Tetanus vaccine generally lasts for about 5 years in fully immunized and booster immunized persons. Tetanus vaccine is not required for injuries sustained less than 5 years after the last dose of tetanus vaccine, except in patients with severely contaminated wounds. Patients who have been fully immunized and booster immunized do not need to receive tetanus vaccine again if they are injured within 5 years after the last tetanus vaccination. Therefore, the effect of tetanus vaccine is usually maintained for about 5 years. However, patients with severely contaminated wounds or those who were not fully immunized before the injury need to be vaccinated again. After tetanus vaccination, patients may experience localized redness, swelling, pain, itching or have adverse reactions such as low-grade fever, fatigue and headache. Injection is contraindicated in patients with severe illness, fever, and history of allergy.