Government data misused to question COVID-19 vaccine safety

All vaccines, including those against COVID-19, go through rigorous clinical trials, in some cases involving tens of thousands of people. But these trials might not involve enough people with a particular risk factor, meaning that some issues might go unnoticed by researchers in the early stages. In addition, any vaccine can cause rare side effects that appear later.

Launched in 1990, VAERS is used by the CDC and the FDA to detect “worrying patterns or unusual and unexpected changes” that could indicate a safety concern once the vaccines are on the market, according to one. 2015 academic article published by researchers from both agencies in the journal Vaccine.

“VAERS is important because it can capture events that have not been collected systematically as part of active surveillance in clinical trials, rarer than what would have been observed in trials due to the limited size samples, or occur in populations that have not been adequately studied in clinical trials, ”says Steven J. Jacobsen, MD, acting executive director of the Marshfield Clinic Research Institute, a Wisconsin-based medical research institute , and past president of the American College of Epidemiology.

For example, government researchers have investigated reports of myocarditis, or inflammation of the heart muscle, which have been subjected to VAERS, then alerted the public when it deemed this risk plausible. The CDC said it continues to monitor the development.

VAERS reports alone only communicate that some sort of adverse event, minor or major, occurred after someone received a vaccine. Further work and information is needed to establish whether the vaccine was the cause.

CDC and FDA physicians, epidemiologists, and statisticians assess the number of reports received, the type of events reported, and the number of doses dispensed. Then, they compare the rate of an adverse event reported in VAERS with the rate of the same adverse event with other vaccines.

So while reports alone usually cannot link a vaccine to an adverse event, it can play an important role.

“VAERS can often provide the first insight into potential vaccine safety issues,” The 2015 vaccine according to an article by CDC and FDA researchers.

If it detects potential safety issues, CDC and FDA researchers can then investigate further using other systems, such as the CDC’s Vaccine Safety Datalink, which receives more specific data from the big nine. health organizations and can help measure “attributable risk,” says Emory’s Orenstein.