CDC: VAERS Reporting Database is ‘Success Story’ for Vaccine Safety

The public health reporting system that collects information on adverse vaccination effects played a large role in public health agencies’ decision to temporarily pause the Johnson & Johnson-developed COVID-19 vaccine last week.

With more than 7 million of the particular brand’s vaccines administered throughout the U.S., the Centers for Disease Control and Prevention and the Food and Drug Administration recommended a temporary pause in its distribution as they investigate next steps amid reports of some individuals afflicted with blood clots shortly after inoculation.

During an April 14 emergency meeting with CDC’s Advisory Committee on Immunization Practices (ACIP), health leaders discussed the critical role of the Vaccine Adverse Event Reporting System (VAERS), a database developed in 1990 co-led by CDC and FDA that tracks and analyzes reports of adverse events after any vaccination in the U.S. According to its website, the system helps public health officials determine whether additional evaluation is necessary for vaccine safety.

According to an FDA announcement, six women developed a “rare and severe type of blood clot,” along with low levels of blood platelets, after receiving the Johnson & Johnson-developed vaccine. The pause will ensure safety for the patients by enabling health care professionals to recognize and properly treat and report these events.

During the post-authorization phase of a vaccine, there are a variety of ways that adverse events can be reported. One is directly reporting it through VAERS. Another is via the V-safe program, a smartphone-based tool that sends text messages to inquire about patients’ experiences of the vaccine. This information is then sent to VAERS. Either way, VAERS collects all such information on vaccine effects.

“If any adverse events come directly to the company, we have an expedited reporting process, whereby we process those cases and send them immediately to the FDA, European Health Authority and other global health authorities so there is a continuing, sustained, rapid reporting of events between the companies and the health authorities,” said Dr. Aran Maree, chief medical officer for the Janssen Pharmaceutical Companies of Johnson & Johnson.

VAERS helped the agency identify four of the cases. Still, there are some limitations in the system. There is a “slight lag in reporting” through VAERS, and “for privacy reasons, there is significant redaction of some of the data fields, and it is not possible to follow up for further information or evaluation beyond what is presented in the preliminary report,” Maree noted.

Also, because VAERS is a passive reporting system, it relies on health care providers to recognize and report potential adverse events promptly in order to effectively detect rare and serious adverse events that may present a safety problem.

Still, the data collected via VAERS is being used alongside the evolving research on COVID-19 and other adverse effects of the vaccine. Plus, without the system, the decision to pause this particular vaccine might not have come as quickly.

“Early recognition was critical for timely and appropriate management,” said Dr. Grace Lee, chair of ACIP COVID-19 Vaccine Safety Technical Subgroup (VaST). “Vaccine safety is paramount to all of us. In this situation, we are appreciative that our global safety monitoring efforts and the VAERS team enabled the CDC and FDA to rapidly detect these adverse events.”

“VAERS performed exactly as intended in this case,” said Dr. Tom Shimabukuro with CDC’s National Center for Emerging and Zoonotic Diseases. “This is a good example of how robust the U.S. vaccine safety monitoring is and how, in this case, during a mass vaccination program, the system worked and VAERS functioned as intended. This is an example of a success story for vaccine safety.”

Though this particular vaccine is just one of three currently available and being actively distributed nationwide, the temporary pause could negatively impact the widespread effort to get as many people vaccinated as possible as part of the pandemic response. To identify the proper next steps, Lee added that timely and transparent communication with health care providers will help drive early recognition and appropriate treatment for patients who face these adverse events following vaccination.

“VaST plans to focus on enhanced case identification, including patients who were recently vaccinated with the Janssen vaccine. We continue to encourage patients to enroll in V-safe and for providers and patients to report to VAERS,” said Lee. “This is incredibly helpful for all of us and we hope to continue to support vaccine safety monitoring.”

The voting members of ACIP, who will determine next steps of the vaccine distribution April 23 and will use data collected through VAERS and other reporting systems to inform those steps, Lee said.