Let's talk vaccines: ᵀʸᵖᵉˢ ᵒᶠ ⱽᵃᶜᶜⁱⁿᵉˢ

There are four types of vaccines currently available:

(1) Live virus vaccines use the weakened (attenuated) form of the virus. The measles, mumps, and rubella (MMR) vaccine and the varicella (chickenpox) vaccine are examples.

(2) Killed (inactivated) vaccines are made from a protein or other small pieces taken from a virus or bacteria. The whooping cough (pertussis) vaccine is an example.

(3) Toxoid vaccines contain a toxin or chemical made by the bacteria or virus. They make you immune to the harmful effects of the infection, instead of to the infection itself. Examples are the diphtheria and tetanus vaccines.

(4) Biosynthetic vaccines contain manmade substances that are very similar to pieces of the virus or bacteria. The Hepatitis B vaccine is an example.

In some cases, like with the MMR vaccine, you need more than one dose of a vaccine to build strong immunity. With others, like the tetanus vaccine, your immunity wears off over time and you need occasional “booster” vaccines. In the case of the flu vaccine, the main targets of the immune response shift slightly from year to year, depending on which flu virus strains are circulating most that year, so you need a vaccine every year.

{You can find all the sources I used by clicking here.}