Recently, the Food and Drug Administration (FDA) and the Centers for Disease Control (CDC) paused using the Johnson and Johnson covid vaccine. Vaccine monitoring reports indicated a complication known as thrombosis with thrombocytopenia syndrome (TTS) or blood clots. Fifteen women between the ages of 18-49 experienced this complication, and three died.
Now the FDA and CDC have reversed their pause and are allowing further use of this vaccine. Does that make the vaccine unsafe? According to medical experts, this process worked to make the vaccine safer, not less safe.
Vaccine Approval and Monitoring
When a new vaccine is introduced, the FDA is responsible for determining if it's safe and effective. How well a vaccine works is studied in clinical trials, large-scale tests with people who volunteer to receive the vaccine. The clinical trials attempt to use as many different types of people as possible, including people of different:ages; races; and medical histories.
Based on a broad spectrum of people, clinical trials help determine if there are common complications or side effects to a vaccine and how severe those side effects are. However, the number of people in a clinical trial is limited, so not every possible type of person receives a test vaccine. During the Johnson and Johnson covid vaccine clinical trials, no one experienced the TTS blood clot complication.
The FDA approved the use of the Johnson and Johnson Covid vaccine under an Emergency Use Authorization. This authorization is only used when a vaccine’s clinical trials show it to be safe, at least 50% effective, and there is an urgent need for a vaccine. Because the World Health Organization declared Covid to be a worldwide pandemic, the urgent need for a vaccine became a priority.
Once approved, the CDC monitors the distribution and use of a vaccine. The CDC collects additional data on how safe and effective a vaccine is for the general population. As more people receive the vaccine, other side effects and complications may occur. When the FDA and CDC paused Johnson and Johnson Covid vaccine use, over 6.8 million people had received the vaccine.
The CDC uses a system known as VAERS, the Vaccine Adverse Event Reporting System, to report and track vaccine side effects and complications. When the TTS blood clot complication appeared in the VAERS database, the CDC and the FDA paused the vaccine’s use to study the complication further.
Pause Versus Recall
The Johnson and Johnson Covid vaccine was paused, not recalled. According to the FDA and CDC, the pause allowed researchers to review the data specific to the blood clots and determine if it was enough of a risk to halt, or recall, the use of the vaccine.
The FDA defines a recall as “a voluntary action taken by a company to remove a defective drug product from the market.” Researchers at Yale Medicine state a pause is not uncommon when a new vaccine or drug is used. Among other vaccines that were paused, the polio vaccine was paused shortly after distribution began.
Two hundred and fifty people contracted polio from the vaccine. Researchers attributed this to a faulty manufacturing process with the vaccine. The scientists corrected the problem, and the vaccine is now widely used.
The CDC advisory committee reviewed the data associated with the blood clots. They found that the instances of this complication were very rare. Historically, any vaccine can have rare complications that don’t affect most people in the general population. The CDC did not find the instances of this complication to be a significant risk when they compared how many people had complications to those who did not.
The CDC monitoring system is designed to identify vaccine complications. Although the blood clot complication wasn’t contained to one geographical area or age, the system did identify it for further study. Because scientists and doctors are now aware of this risk, they can recognize it quickly and treat it if it occurs.
The risk to the general population is minimal, and doctors are now better able to manage it if it does happen. This improved knowledge about the vaccine caused the FDA and CDC to reverse their pause and again allow the use of the vaccine.