How Do We Know Vaccines Are Safe?

Key takeaways

• Vaccine safety is evaluated through research, clinical trials and FDA review.
• Ongoing monitoring tracks vaccine effectiveness and identifies rare issues.
• For older adults, vaccination can help lower risks from serious infections.

Summary

Vaccine safety is the focus of this discussion, which explains how vaccines train the immune system to recognize and respond to germs before infection can cause serious harm. Experts describe how vaccines are tested through multiple stages of research and clinical trials before receiving approval for public use.

The transcript also highlights the extensive safety monitoring that continues after vaccines are introduced, allowing public health agencies to track outcomes and adjust recommendations when needed. While mild side effects can occur, experts note that vaccines are among the most carefully studied tools in medicine and can help protect older adults from severe illness and hospitalization.

The key takeaways and summary were created with the assistance of generative AI. An AARP editor reviewed and refined the content for accuracy and clarity.

Full transcript

[0:00:00] Rachel Nania: When you look at decades of research and real-world data, vaccines

[0:00:03] have consistently been shown to save lives, reduce the risk of serious disease

[0:00:08] and help people stay healthier longer.

[0:00:10] But there’s a lot of confusion and controversy surrounding

[0:00:13] vaccines these days, which can make it hard to know what’s true.

[0:00:17] So how do we know vaccines are safe?

[0:00:21] To understand the safety of vaccines, first let’s take a

[0:00:24] look at what a vaccine does.

[0:00:26] Dr. William Schaffner: What vaccines do is prime and educate our immune system

[0:00:32] to fight off the germ when it’s there,

[0:00:34] so our body is ready to fight off the germ when it attacks us.

[0:00:39] Rachel Nania: Instead of making you fight a full infection, a vaccine introduces a

[0:00:43] harmless version of a germ or instructions for making a harmless piece of it, and

[0:00:48] this teaches your immune system what to look for and how to respond, which is

[0:00:52] especially important for older adults.

[0:00:55] Dr. William Schaffner: Our immunity as older adults is not as strong

[0:00:58] as it was when we were younger, and therefore, should we become infected,

[0:01:03] we’re more likely to get seriously ill and require hospitalization.

[0:01:07] Rachel Nania: Vaccines in the U.S. follow a rigorous pathway before

[0:01:10] they ever reach the public.

[0:01:12] That includes research, clinical trials and approval by the

[0:01:15] Food and Drug Administration.

[0:01:17] Dr. William Schaffner: The standards of safety for the licensure of vaccines

[0:01:20] are much higher than they are for a drug that’s used to treat a serious illness.

[0:01:28] Because we give vaccines to healthy people, therefore, the standards for

[0:01:32] safety must be very, very high indeed.

[0:01:36] The way we assess vaccine safety is by giving the vaccine under very close

[0:01:40] supervision to volunteers, a small group, a larger group, and then a very

[0:01:45] large group of volunteers to make sure that the vaccines are indeed safe.

[0:01:52] Rachel Nania: Once vaccines are in use, doctors, researchers and public health

[0:01:56] agencies continue tracking safety data.

[0:01:58] Dr. William Schaffner: The United States has the most comprehensive ongoing

[0:02:03] vaccine safety effectiveness assessment program of any country in the world.

[0:02:09] And if an issue comes up, then we can make adjustments in

[0:02:14] our vaccine recommendations.

[0:02:16] There have been occasions where vaccines have actually been taken off the market

[0:02:21] because of a very rare adverse event.

[0:02:25] But vaccines have not been associated with widespread serious illnesses.

[0:02:31] Rachel Nania: Despite this, some people are unsure about getting them.

[0:02:35] Vaccine hesitancy isn’t new.

[0:02:37] It has existed as long as vaccines themselves, and it’s usually driven by

[0:02:41] concerns about safety, effectiveness and cultural or even religious beliefs.

[0:02:46] More recently, social media has amplified some of these concerns, including

[0:02:50] those that aren’t supported by facts.

[0:02:53] Another concern about vaccines are the mild side effects that can

[0:02:56] occur after getting the vaccine.

[0:02:57] Dr. William Schaffner: There are some individuals who get vaccinated

[0:03:00] who for sure will have a sore arm, some swelling and redness.

[0:03:05] Other people will get a day of headache, feel poorly, their appetite

[0:03:10] won’t be as good for a day or so.

[0:03:13] But these are very modest prices to pay in order to get protection

[0:03:19] from illnesses that can put you into the hospital and can kill you.

[0:03:23] Rachel Nania: No medical intervention is completely risk-free, but decades

[0:03:27] of research, extensive testing and ongoing safety monitoring

[0:03:31] have made vaccines one of the most carefully studied tools in medicine.

[0:03:35] If you have questions or concerns, talk to your doctor, and they can

[0:03:39] help you sort out facts from fear.

[0:03:40] Dr. William Schaffner: As I like to say, disease bad, vaccines good.

[0:03:46] Get vaccinated.

[0:03:47] Rachel Nania: For more in-depth health news and information,

[0:03:50] visit aarp.org/health