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How vaccines actually work: A simple guide

Vaccines based on an organism component

These vaccines use only parts of the germ, like a protein or sugar. Your immune system learns to recognize it without being exposed to the whole germ. These vaccines protect against:

  • COVID-19.
  • Hepatitis B.
  • Human papillomavirus (HPV).
  • Meningococcal disease.
  • Pneumococcal disease.
  • Shingles.
  • Whooping cough, also called pertussis.

These vaccines can generally be tolerated by most people, including those with weakened immune systems or serious health conditions.