The U.S. Food and Drug Administration study did not find evidence that Pfizer's COVID-19 vaccine is directly linked with blood clots, as some have claimed.
The researchers collaborated with the FDA team and found that Pfizer's COVID-19 vaccine does not directly cause blood clots. The study did show that some older recipients of the vaccine were linked with pulmonary embolisms, but doesn't necessarily prove an association.
The misconceived study, published in December 2022 by the journal Vaccine, led to a feud on social media, with one user tweeting: “So… is @Pfizer ever going to mention in their jab ads they carry the risk of side effects, including but not limited to: Myocarditis, pericarditis, blood clots, stroke, Bell’s palsy, chronic fatigue syndrome, just to name a few?"
Another user even tweeted: “#FDA Confirms #Pfizer Causes Clots! Big Pharma’s #Bio-Terrorism Slowly Exposed As People Die Suddenly The FDA has finally admitted that the Pfizer vaccine causes blood clots! Are they FINALLY owning up to the fact that they were WRONG?" and received more than 1,330 views.
The FDA did not make such a statement, and individuals across social media misinterpreted certain wording online. The research team studied vaccine recipients over the age of 65, utilizing Centers for Medicare & Medicaid Services data from December 2020 through January 2022.
They eventually found that blood clots, medically referred to as pulmonary embolisms, were linked with the vaccine by meeting such a threshold. Despite the result, researchers revealed that "the signals are still under investigation and require more robust study."
“The FDA has not found any new causal relationships between the Pfizer-BioNTech COVID-19 Vaccine and potential adverse events of special interest identified in 2021," shared FDA press officer Abby Capobianco with The Associated Press.
“The FDA continues to find that the Pfizer-BioNTech COVID-19 Vaccine meets the FDA’s rigorous standards for safety and effectiveness,” added Capobianco. The research also said new research data "should be interpreted cautiously" as they do not prove a causal link between the vaccine and adverse events.
“An early warning system does not prove that the vaccines cause these outcomes,” and continued that the “FDA strongly believes the potential benefits of COVID-19 vaccination outweigh the potential risks of COVID-19 infection.”
The study also lineated critical points of the research, including that the study did not take into consideration underlying risk factors like comorbidities among certain vaccine recipients, which can lead to differing results. The team also disclosed that data gained may under or overestimate specific conditions and that the study outcome "may not be generalizable to those younger than 65 years.”
"There was a slightly increased signal in that vaccine compared to the other ones they tested,” cardiologist and professor at Mount Sinai’s Icahn School of Medicine Dr. Jeffrey Olin told the Associated Press.
He said that “a much more sophisticated study” is necessary to assess causation. Moreover, because study participants were 65 and older, they probably had more comorbidities linked with blood clotting.
What does the COVID-19 vaccine do?
COVID-19 is a type of vaccine that helps our bodies build an immune system to the virus. The vaccine itself cannot give you COVID-19 and acts as a shield when your body encounters the virus. The vaccine does not interfere with our DNA, meaning they do not change our genes in any way. The vaccines do not contain any live virus and thus cannot give you COVID-19.
As of today, there are three main COVID-19 vaccine types authorized in the United States, including mRNA, viral vector, and protein subunit. All three vaccines help our bodies develop immunity against the COVID-19 virus. mRNA vaccines include Pfizer-BioNTech or Moderna, and the Protein subunit vaccine includes Novavax. The Viral vector vaccine is Johnson & Johnson’s Janssen vaccine. Overall, around 80.7 percent of individuals in the United States received at least one dose of the COVID-19 vaccine, and 68.9 percent have been fully vaccinated.