We talked about how a vaccine becomes approved in the first place (through studying lots of “clinical trials”) but how do we ensure that it remains safe after that? Sometimes, when a new medication (or vaccine) is used for lots of people, we may find that someone reacts differently than we expected. For whatever reason, that person’s body responds different than the people who were originally in the clinical trials. Usually this is very rare, but it is still information that we want to know.
Luckily, since vaccines are used so much and are so important for people to receive, there are THREE different ways that we make sure they continue to be safe.
- Vaccine Adverse Event Reporting System (VAERS): a place to make a note of any type of adverse event (side effect) of a vaccine.Anyone, including patients, parents, and health care providers, can submit a report
- Vaccine Safety Datalink (VSD) and Post-Licensure Rapid Immunization Safety Monitoring (PRISM): Two networks (or groups) of healthcare organizations across the country. Between the two, they monitor the health information of over 200 million people! Scientists use this information to continually monitor vaccine safety.
- Clinical Immunization Safety Assessment Project (CISA): A combined effort between the Center for Disease Control (CDC), 7 research centers, and US healthcare providers. The purpose of this project is to do more research on vaccine safety, come up with ideas to prevent adverse reactions from vaccines, and serve as a resource for your healthcare provider to answer complex questions about vaccine safety for specific patients.
One example of how this information was used is with the vaccine for polio. Back in the day, children used to get a live version of the polio vaccine. After collecting lots and lots of data, we learned that a very small number of children actually developed polio after being vaccinated.
Pretty scary, huh?
….but how many children did this actually affect?
1 child out of 1 million
But that was still TOO MANY to be considered safe. So what happened? The guidelines were changed so that children were given inactivated polio vaccine (IPV) instead of oral polio vaccine (OPV). It is impossible for the inactivated polio vaccine to give your child polio.
The risk of catching polio if you weren’t immunized was WAY bigger than the risk of getting it from the vaccine, but that still didn’t make it safe enough to use.
That makes me feel a whole lot better about how vaccines are monitored and what makes them safe, what about you?