How Vaccines are Made

How Vaccines Are Made

The Research and Development Process

Before vaccines are produced, they go through a long process of research and development. Often, this takes 10 to 15 years! First, researchers will test a vaccine on mice and adjust the ingredients as needed to make sure it effectively prevents disease. After that, the vaccine is tested through a process called clinical trials. Clinical trials start small with just a few people but grow to include thousands of healthy volunteers. These trials measure how safe the vaccine is in people and how common side effects are. The Food and Drug Administration (FDA) then reviews all the data from the research and development process and votes on whether or not to approve and license the vaccine. After this, the CDC and other partner organizations meet to decide on whether to recommend it to the US population (or just a specific group of people at risk for that vaccine-preventable disease). Finally, researchers continue to monitor the vaccine to ensure it continues to be safe.

The Science of Vaccines

Vaccines are made using products from, pieces of, or whole viruses or bacteria.  The vaccine products or pieces cannot harm recipients, and whole bacteria or viruses are weakened or killed before they are used. This allows a person’s immune system to develop antibodies, or defenders, against the disease without actually getting the disease.

First, researchers determine how the virus and bacteria will be modified to make it safe. Then vaccines are created through a general three-step process:

  1. An antigen is made. An antigen is something that causes the immune system to produce antibodies against it. For vaccines, antigens are made from viruses or bacteria.
  2. The antigen is separated out from the cells used to create it.
  3. The antigen is added to other vaccine ingredients, including adjuvants, stabilizers, and preservatives. Adjuvants help boost the body’s immune response to a vaccine. Stabilizers increase the vaccine’s storage life. Preservatives prevent contamination of vaccines, such as bacteria that might grow in vials that hold multiple doses.

The Bottom Line

It is important to remember that vaccines undergo a rigorous development process. This includes oversight during the vaccine manufacturing process, scrutiny from the FDA, and careful consideration of all the data by the CDC and its partners. The process to get a vaccine approved involves years of testing to prove it is safe and effective. Thereafter, vaccines are continually monitored for safety. The recommended vaccines are studied to be given at the same time as other vaccines. They work together to protect your child. Visit the CDC website to learn more about the development of safe and effective vaccines.