The US Vaccine Adverse Event Reporting System (VAERS) was established in 1990 by the FDA and CDC an early warning system to detect possible safety problems for US-licensed vaccines. It “is a passive reporting system, meaning success depends on medical personnel, patients, and families taking the initiative to file reports”. [1]
In 1986 vaccine manufacture liability was removed, so this system became the main means of post-marketing surveillance of short and long-term vaccine safety. The data collected is used to make claims about vaccine safety, which is only as good as the adverse event reports entered. VAERS went online in 2002.
The Harvard study commissioned by the CDC in 2007, concluded that “fewer than 1% of vaccine adverse events are reported” to VAERS.
With this passive reporting system, that many US healthcare providers are not even aware they are require by law to report to, makes the robustness of the under-reported data poor, and thus affects the system’s ability to effectively identify “warning signals” or support the common claim that there is a “1 in a million” risk.
A controlled study looking at anaphylaxis reactions following mRNA COVID-19 vaccines showed 2.47 events per 10,000 jabs (0.027%), yet VAERS data reports indicated only 2.5 to 4.7 events per 1,000,000 jabs, a 100% difference. This is in line with the conclusions of the 2010 Harvard report.