Prevention of tetanus is achieved by vaccination with which vaccine?

• A. Diphtheria toxoid vaccine
• B. Pneumococcal conjugate vaccine
• C. Meningococcal vaccine
• D. Tetanus toxoid vaccine

Answer: (D)

Tetanus prevention relies on neutralizing the toxin produced by the bacterium Clostridium tetani. The vaccine uses a tetanus toxoid, which is an inactivated form of the toxin, to safely train the immune system to make antibodies against it. Those antibodies can then bind the real toxin if exposure occurs, blocking its ability to disrupt nerve signaling and causing disease. The other vaccines listed target different pathogens or toxins and do not confer protection against tetanus—for example, diphtheria toxoid protects against diphtheria toxin, the pneumococcal conjugate vaccine targets Streptococcus pneumoniae, and the meningococcal vaccine targets Neisseria meningitidis. In practice, tetanus prevention is achieved with tetanus toxoid–containing vaccines such as DTaP or Tdap, with boosters as recommended.