There are several different types of vaccines. Each type uses a different mechanism to teach your immune system how to fight off certain kinds of germs and the diseases they cause. 

Inactivated Vaccines

Inactivated vaccines use the dead version of the germ that causes a disease. 

Inactivated vaccines don't provide immunity that lasts as long as live vaccines, so you may need several booster doses over time to have ongoing immunity against disease. 

Examples of inactivated vaccines are:

  • Flu
  • Hepatitis A
  • Polio
  • Rabies

Live-attenuated Vaccines

Live vaccines use a weakened form of the germ that causes a disease. 

Since these vaccines are so similar to the disease they help prevent, they create a strong and long-lasting immunity. One or two doses of most live vaccines will give you a lifetime of protection against a germ and the disease it causes. 

Examples of live vaccines are:

  • MMR (Measles, mumps, rubella)
  • Rotavirus 
  • Smallpox/mpox
  • Chickenpox 

Messenger RNA (mRNA) Vaccines

mRNA vaccines make proteins in order to cause an immune response. 

mRNA vaccines have several benefits compared to other types of vaccines, including shorter manufacturing times and, because they do not contain a live virus, no risk of causing disease in the person being vaccinated. 

Examples of mRNA vaccines are:

  • COVID-19 (Pfizer, Moderna)

Subunit, Recombinant, Polysaccharide, and Conjugate Vaccines

Subunit, recombinant, polysaccharide, and conjugate vaccines use specific pieces of the germ. 

Since these vaccines use specific parts of a germ, they give a very strong immune response that's targeted to those key parts of the germ. They can be used on almost everyone, including people with weakened immune systems and long-term health problems. 

You may need booster shots of these vaccines to get ongoing protection against diseases. 

Examples of subunit, recombinant, polysaccharide, and conjugate vaccines are:

  • Hepatitis B
  • HPV
  • Whooping cough 
  • Pneumococcal disease 
  • Shingles 
  • COVID-19 (Novavax)

Toxoid Vaccines

Toxoid vaccines use a toxin made by the germ that causes a disease. 

This creates immunity to the parts of the germ that cause disease instead of the germ itself. The immune response targets the toxin instead of the whole germ. 

Examples of toxoid vaccines are:

  • Diphtheria
  • Tetanus 

Viral Vector Vaccines

Viral vector vaccines use a modified version of a different virus as a pathway to deliver protection. 

The viral vector vaccine uses the harmless virus to pass the instructions for making antibodies from the disease-causing virus into your cells, creating protective immunity against it. 

Examples of viral vector vaccines are:

  • COVID-19 (Johnson & Johnson)
  • Ebola