15. Considerations Regarding the Vaccine Adverse Event Reporting
System (VAERS)
The Food and Drug Administration’s Vaccine Adverse Event Reporting
System (VAERS) is an imperfect but valuable resource for identifying
potential adverse reactions to vaccines. Established through
collaboration between the CDC and FDA, VAERS is “a national early
warning system to detect possible safety problems in U.S.-licensed
vaccines.” According to the CDC it is “especially useful for detecting
unusual or unexpected patterns of adverse event reporting that might
indicate a possible safety problem with a vaccine.”
(https://vaers.hhs.gov/about.html)
Even the CDC recognizes that adverse events reported to VAERS represent
“only a small fraction of actual adverse events [207]. A widely
cited report noted that less than 1% of all vaccine-related adverse
events are reported to VAERS [208]. That assertion, though, has no
citation so the basis for the claim is unclear. Rose (2021) published a
much more sophisticated analysis of VAERS data to offer an estimate of
underreporting by a factor of 31 [209]. While it is impossible to
determine underreporting with precision, the available evidence is that
underreporting very strongly characterizes the VAERS data. The
information presented below should be understood in that light.