Are Vaccines Safe? |

Are Vaccines Safe?

Posted on August 26, 2014

Hello again! Today I want to share some facts about how the U.S. Food and Drug Administration (FDA) ensures the safety and effectiveness of every vaccine before it is made public. Have you or someone you know avoided getting vaccinated because you were afraid? I hope this article helps lift those fears.

The United States’ long-standing vaccine safety system ensures that vaccines are as safe as possible. In fact, currently, the United States has the safest, most effective vaccine supply in its history.

Before a new vaccine is given to people, extensive lab testing is done that can take several years. Once testing in people begins, it can take several more years before clinical studies are complete and the vaccine is licensed.

How a New Vaccine Is Developed, Approved and Manufactured

Food and Drug Administration (FDA) sets rules for the three phases of clinical trials to ensure the safety of the volunteers.

Phase 1

Researchers test vaccines with adults first. Between 20-100 healthy volunteers receive the test vaccine. Researchers study to determine:

Is this vaccine safe?
Does this vaccine seem to work?
Are there any serious side effects?
How is the size of the dose related to side effects?

Phase 2

Several hundred additional, healthy volunteers receive a test vaccine and researchers determine:

What are the most common short-term side effects?
How are the volunteers’ immune systems responding to the vaccine?

Phase 3

Hundreds or thousands of volunteers participate in the Phase 3 test, after which researchers determine:

How do people who get the vaccine and people who do not get the vaccine compare?
Is the vaccine safe?
Is the vaccine effective?
What are the most common side effects?

The FDA licenses a vaccine only if:

It’s safe and effective.
The benefits outweigh the risks.

Vaccines are made in batches called lots.

Manufacturers must test all lots to make sure they are safe, pure and potent. The lots can only be released once FDA reviews their safety and quality.

The FDA inspects manufacturing facilities regularly to ensure safety and quality.

Tomorrow, I’ll share some facts about the positive impact of making the decision to vaccinate your children, and the potential negative impact of deciding not vaccinate.

For more information, visit http://www.fda.gov/cber

Don’t forget to take my weekly immunization quiz, if you haven’t already!