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Making Vaccines
Similar-pathogen vaccine: smallpox virus

smallpox step 1 Step 1
Use the sterile petri dish to collect fluid from pustules on the cow's udder.

  To create a vaccine that will protect you against a pathogen, you usually begin with that pathogen and alter it in some way. Not so with smallpox. To create this vaccine, you begin with another virus that is similar to the smallpox virus, yet different enough not to bring on the smallpox disease once it enters your body. This similar virus is cowpox.

The cow to the left has been intentionally infected with cowpox virus. The fluid that you collect from virus-caused pustules on the cow's udder contains many copies of the virus.

Smallpox step 2 Step 2
Use the purifier to isolate the viruses.

  Smallpox vaccines contains cowpox viruses but not the bacteria and other impurities found in the fluid collected from such pustules.

To make the vaccine, therefore, you'll need to separate the cowpox viruses from the rest of the fluid.

Smallpox step 3 Step 3
Fill the syringe with the purified cowpox viruses.

  The smallpox vaccine is a live vaccine; the cowpox viruses it contains will invade cells in your body, multiply, and spread to other cells in your body, just as the smallpox viruses would. And as with smallpox, the body's immune system will mount an attack against the cowpox and subsequently always "remember" what it looks like. Then, if cowpox or the similar smallpox ever enters the body, the immune system will quickly get rid of the invaders.

Smallpox done Done
The smallpox vaccine is complete.

Select another pathogen.

  Congratulations. You have just created a vaccine for smallpox.

At one time, cows were used to create the smallpox vaccine. In fact, the decades-old stockpile in the U.S. today was made using live calves through a process similar to the one outlined here. Advancements in biotechnology, however, have led to more efficient procedures that make use of bioreactors.

Smallpox icon
Similar-pathogen vaccine:
smallpox virus
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Attenuated vaccine:
measles virus
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Killed vaccine:
polio virus
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Toxoid vaccine:
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Subunit vaccine:
hepatitis B
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Naked-DNA vaccine:

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