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Making Vaccines
Killed vaccine: polio virus

Polio step 1 Step 1
Use the tissue culture to grow new viruses.

  The goal in creating a killed vaccine is to disable a pathogen's replicating ability (its ability to enter cells and multiply) while keeping intact its shape and other characteristics that will generate an immune response against the actual pathogen. When the body is exposed to the killed polio vaccine, its immune system will set up a defense that will attack any live polio viruses that it may encounter later.

To produce this vaccine, you first need many copies of the polio virus. You can grow these in a tissue culture.

Polio step 2 Step 2
Use the purifier to isolate the polio viruses.

  The polio virus uses the cells within the tissue culture to produce many copies of itself.

These copies of the virus need to be separated from the tissue culture.

Polio step 3 Step 3
Use formaldehyde to kill the viruses.

  There are several ways to inactivate a virus or bacteria for use in a vaccine. One way is to expose the pathogen to heat. This is how the bacteria in the typhoid vaccine is inactivated. Another way is to use radiation.

For the polio vaccine developed by Jonas Salk in 1954, formaldehyde was used. You'll use formaldehyde in creating your polio vaccine, too.

Polio step 4 Step 4
Fill the syringe with the killed polio virus.

  The dead viruses in your polio vaccine will not produce a full immune response when injected in a body. This is true for all vaccines that are not live. For this reason, these vaccines usually require booster shots.

Polio done Done
The polio vaccine is complete.

Select another pathogen.

  Congratulations. You have produced a killed polio vaccine.

There are two polio vaccines widely used today. One is Salk's killed vaccine; the other is a live-attenuated vaccine first developed by Albert Sabin.

In addition to polio and typhus, killed vaccines are used to prevent influenza, typhoid, and rabies.

Smallpox icon
Similar-pathogen vaccine:
smallpox virus
  Measles icon
Attenuated vaccine:
measles virus
  Polio icon
Killed vaccine:
polio virus
Tetanus icon
Toxoid vaccine:
  Hepatitis icon
Subunit vaccine:
hepatitis B
  HIV icon
Naked-DNA vaccine:

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