Home Misleading: The FDA has admitted that the Pfizer vaccine is linked to blood clotting in older people.

Misleading: The FDA has admitted that the Pfizer vaccine is linked to blood clotting in older people.

By: Sandesh M

January 9 2023

Share Article: facebook logo twitter logo linkedin logo
Misleading: The FDA has admitted that the Pfizer vaccine is linked to blood clotting in older people.

Fact-Check

The Verdict Misleading

The FDA study has been misinterpreted. It found some instances of pulmonary embolism but did not establish a definitive link to vaccines.

Context

American doctor and lawyer Simone Gold tweeted on December 18, 2022, that the U.S. Food and Drug Administration (FDA) has "admitted" that the COVID-19 vaccine is linked to blood clotting. She added a link to an article published on December 17, 2022, by the Epoch Times - a right-wing paper with a history of publishing stories questioning vaccine safety - to back this claim. The article, "Pfizer's COVID-19 Vaccine Linked to Blood Clotting: FDA" refers to a study published by the journal "Vaccine" in December 2022. However, the claim is misleading.

In Fact

We reviewed the article and the study Gold cited and found that her claim is a misleading interpretation of a study on vaccine safety in the elderly aged 65 and older. The headline did not convey the information contained in the article accurately.  

In collaboration with researchers, the FDA looked at the data of 17.4 million senior citizens aged 65 and older in the U.S. who had received the COVID-19 vaccine from December 11, 2020, to January 15, 2022. According to the details of the study, researchers analyzed various health-related events in the elderly post-vaccination. They found four outcomes met the threshold for a "statistical signal." After adjustments, only one outcome of pulmonary embolism (which refers to blood clots in the lungs) met the threshold criteria for a statistically significant signal.

Meaning there was some association between the vaccine and instances of pulmonary embolism. The researchers noted this was not evidence of causality, and eventually concluded that the statistical signals do not prove that vaccines cause blood clots. The study stated, "The statistical signals of four serious outcomes are not necessarily causal and may be due to factors potentially unrelated to vaccination." They noted that the signals need to be further evaluated in robust studies to determine the exact nature of the link. 

There were also inherent limitations to the study, which were outlined by the researchers, including the fact that it was based on data received from an 'early warning system' (which couldn't provide data on causality), underlying comorbidities and other risk factors among some vaccine recipients that may have led to differing results. 

A key issue highlighted in the discussion section was that its dataset came from the Centers for Medicare and Medicaid Services, using the Medicare health insurance database. The data analyzed related to around 17 million Medicare recipients. "For example, the elderly Medicare population that received the [Pfizer BioNTech] vaccine differed from other elderly COVID-19 vaccinated populations, including a preponderance of nursing home residents and populations with a higher comorbidity burden," the researchers noted.

The researchers pointed out that the outcomes may be due to existing conditions preceding the vaccination and other factors that could not be accounted for. In conclusion, the study warned that the findings are from an early warning system meant for safety monitoring and should be interpreted cautiously.

While there have been concerns over side effects caused by vaccines, the FDA has maintained that the benefits of getting vaccinated are more than the risks involved, something emphasized in this study as well.

The FDA had limited the authorized use of the Janssen COVID-19 vaccine in May 2022 due to complaints about thrombosis in certain individuals. Additionally, the CDC's updated guidance of December 9, 2022, mentions that the Janssen vaccine can be used only in certain situations, whereas previously approved vaccines of Pfizer, Novavax, and Moderna, are recommended. 

The Pfizer vaccine, in particular, has not been linked to an increased risk of blood clots. A study by researchers at Oxford University and several European universities, published in the British Medical Journal (BMJ) found that compared to the Pfizer mRNA vaccine, there was a greater risk of blood clot-related complications after vaccination using the Oxford-Astra Zeneca adenovirus-based vaccine. This study noted that these effects were rare, suggesting they should be considered when planning future immunization campaigns and vaccine development.

Gold has a history of promoting unproven theories about COVID-19. NPR has reported on a speech Gold gave in August 2021, where she told the public to avoid COVID-19 vaccines and prescribed alternative treatments that are found ineffective against the virus (some of which she was willing to prescribe if people booked telehealth appointments with her). Independent fact-checking organizations have previously debunked similar statements made by Gold. 

Reuters, for instance, fact-checked a video featuring a speech by Gold wherein she says that people taking vaccines are testing positive and endorses unproven treatment using Hydroxychloroquine and Ivermectin to treat COVID-19 patients. 

The Verdict

The research study that finds some association between vaccination and blood clots in the lungs is preliminary and clearly states that findings do not prove that the vaccine causes blood clots. The article headline does not validate what researchers interpreted. Therefore, we mark the claim as misleading.


The COVID-19 pandemic has given rise to a lot of potentially dangerous misinformation. For reliable advice on COVID-19, including symptoms, prevention, and available treatment, please refer to the World Health Organization or your national healthcare authority.

Would you like to submit a claim to fact-check or contact our editorial team?

0 Global Fact-Checks Completed

We rely on information to make meaningful decisions that affect our lives, but the nature of the internet means that misinformation reaches more people faster than ever before