A preliminary study reported in the 22 September 2022 issue of ScienceDirect entitled “Serious adverse events of special interest following mRNA COVID-19 vaccination in randomized trials in adults” using publicly available data from Pfizer and Moderna studies, found one serious adverse event for each 800 vaccines. You can review the entire study here:
Two of the authors, Robert Kaplan and Sandler Greenland, recapped their study in an article entitled Why We Question the Safety Profile of mRNA COVID-19 Vaccines in Sensible Medicine (link to the article here), saying:
“Many physicians and scientists believe that vaccination programs are the key to ending the coronavirus pandemic. Some warn that our analysis might harm public health by stimulating more vaccine hesitancy. Yet, if some concerns are valid, remaining quiet could also result in harm and further erode public trust in science.
“We believe that scientists have a responsibility to report suspected hazards to authorities. Consider a 1 in 800 risk of a serious adverse reaction in the context of other vaccines. The 1976 swine flu vaccine was withdrawn after it was associated with Guillain-Barre Syndrome at a rate of approximately 1 in 100,000. In 1999, the rotavirus vaccine Rotashield was withdrawn following reports of intussusception in about 1 or 2 in 10,000. As widely acknowledged, COVID vaccines prevent hospitalizations, and the clinical trials estimated that between 225 and 625 hospitalizations were prevented per million vaccinated persons. But these benefits are likely to be concentrated among vaccinees who are elderly or have chronic illnesses. It is less clear which groups are at risk for serious adverse vaccine reactions. Those at low risk for hospitalization may still be at risk of serious vaccine reactions. We only considered mRNA vaccines and it is not clear that other COVID-19 vaccines confer the same risk.”
There are some limitations to the study, not the least of which is the lack of transparency from Pfizer and Moderna regarding their initial trial data. But the authors of the study pointed out that, “The excess risk of serious adverse events found in our study points to the need for formal harm-benefit analyses, particularly those that are stratified according to risk of serious COVID-19 outcomes. These analyses will require public release of participant level datasets.”
In conclusion, they noted, “Full transparency of the COVID-19 vaccine clinical trial data is needed to properly evaluate these questions. Unfortunately, as we approach 2 years after release of COVID-19 vaccines, participant level data remain inaccessible.”