Facebook Twitter Tumblr Close Skip to main content
A Project of The Annenberg Public Policy Center
SciCheck’s COVID-19/Vaccination Project

Viral Posts Misuse VAERS Data to Make False Claims About COVID-19 Vaccines


This article is available in both English and Español

SciCheck Digest

Social media posts repeatedly misuse unverified data from the Vaccine Adverse Event Reporting System to falsely claim that COVID-19 vaccines are dangerous, and even lethal. But the government database is not designed to determine if vaccines cause health problems.


Full Story

Update, Aug. 26: The Pfizer/BioNTech COVID-19 vaccine, which was previously authorized by the Food and Drug Administration for emergency use, received full approval from the agency on Aug. 23 for people 16 years of age and older.

Millions of people in the United States have safely received COVID-19 vaccines. 

Over 145 million doses had been administered as of March 30, according to the Centers for Disease Control and Prevention, and over 95 million people had received at least one dose of the vaccine. 

Most of those who have reported side effects have said they were minor, such as pain or swelling at the injection site, headaches, chills or fever — which are all consistent with the results of clinical trials. Some people have no side effects at all. And a small number of people (2 to 5 people per million vaccinated) have reported a severe allergic reaction called anaphylaxis, which “almost always” happens within a half an hour of being vaccinated, the CDC says

Yet over and over websites and social media posts improperly cite unverified raw data from the Vaccine Adverse Event Reporting System, an alert system managed by the CDC and the Food and Drug Administration to detect possible safety issues in vaccines, as evidence that the approved COVID-19 vaccines cause deaths and serious events. 

Take this Instagram video, seen by over 36,000 users. In the video, a female narrator walks viewers through the VAERS website and shows them how to find adverse reactions reported to the database after people received the COVID-19 vaccines. 

“Acute myocardial infarction. That is a stroke, if you guys aren’t aware of what that means,” she says incorrectly at the 2:30 mark, as she scrolls down through the results. A myocardial infarction is a heart attack. 

And a couple of minutes later: “Death. And here we are y’all —  this is exactly what you guys wanted to see. Death. Patient passed away in her sleep. Look at all these deaths you guys,” the narrator says scrolling down through dozens of death reports. 

“Do your own research,” writes the account owner on the post, a man under the name “Truth Bombs,” who in a second similar post says he’s not a scientist or a doctor but a concerned father, patriot and digital soldier. “There are very serious side effect from getting the vaccines. Here’s your PROOF.”

Except, as the VAERS website warns, any report submitted to the database “is not documentation that a vaccine caused the event.” 

As we’ve explained before, anyone can submit a report of an event to VAERS, even if it’s not clear that a vaccine caused the problem. All reports are accepted into the database without determining whether the event was caused by a particular vaccine, and therefore, as a disclaimer warns, submissions “may include incomplete, inaccurate, coincidental and unverified information.” 

“One of the main limitations of VAERS data is that it cannot determine if the vaccine caused the reported adverse event,” reads its website. “This limitation has caused confusion in the publicly available data from VAERS WONDER, specifically regarding the number of reported deaths. There have been instances where people have misinterpreted reports of deaths following vaccination as deaths caused by the vaccines; that is not accurate.”

So when VAERS says it has received 2,509 reports of death among people who received a COVID-19 vaccine as of March 29, that does not mean that those deaths were caused by the vaccine. 

In fact, after reviewing medical records, autopsies and death certificates for all of those cases, physicians from both the CDC and the FDA determined that there was “no evidence that vaccination contributed to patient deaths.”

What Is VAERS? 

The Vaccine Adverse Event Reporting System is a national early warning system to detect possible safety issues in vaccines established by the Department of Health and Human Services in 1990. 

The main goal of the database is to serve as a signaling system for adverse reactions, or events, that were not detected during the clinical trials or before a vaccine entered the market. It also complies with a National Childhood Vaccine Injury Act requirement for vaccine manufacturers to report all adverse events and health care providers to report specific adverse events following the administration of a vaccine. 

A nurse fills a syringe with the Moderna COVID-19 vaccine in San Antonio, Texas, on March 29. Photo by Sergio Flores/Getty Images.

VAERS accepts all reports of suspected adverse events, in all age groups. Patients, parents and caregivers are encouraged to report “any clinically important medical event or health problem that occurs after vaccination,” even if they’re not sure if it was a result of the vaccine. These reactions may or may not been caused by a vaccine. 

These reports create a public national database that allows government scientists, and others, to rapidly detect unusual and unexpected patterns that later can be analyzed. 

“It generates perhaps the most rapid type of signal if there was something really awful going on,” Dr. Susan S. Ellenberg, a professor of biostatistics, medical ethics and health policy at the University of Pennsylvania’s Perelman School of Medicine, told us. 

As described on its website, VAERS can detect new, unusual or rare reactions to vaccines; monitor increases in known side effects; assess the safety of newly licensed vaccines; and identify other possible safety issues. 

Dr. Walter Orenstein, associate director of the Emory Vaccine Center in Atlanta, who directed the CDC’s immunization program from 1988 to 2004, told us that VAERS’ unique capacity of generating timely signals makes it an extremely important tool. 

“It is the best signal generator,” he said. “We may miss signals without VAERS.”

Orenstein said VAERS was very helpful in 1998, for example, when it detected a safety issue with the first rotavirus vaccine, RotaShield, as it was being associated with a type of bowel obstruction in infants called intussusception. After the cases were reviewed, the CDC withdrew its recommendation for that vaccine, and the manufacturer took it off the market.  

More recently, as explained in a 2015 study co-authored by scientists from the CDC and FDA, VAERS detected unusual reporting for febrile seizures in young children following a flu shot during the 2010-2011 season. After those episodes, the CDC started listing febrile seizures as a possible side effect of some vaccines for infants and children up to 5 years old.

VAERS Causation Limitation

Although VAERS is great at creating alerts for researchers to follow up, experts agree the database has multiple weaknesses. 

“The biggest limitation is it usually cannot help us assess causation, it provides signals,” Orenstein said. 

As we said, everyone is encouraged to report any medical event or health problem, even if they’re not sure it was caused by a vaccine. The event may have been caused by an underlying medical condition, by a medication or drug taken at the same time, or simply by chance. 

When VAERS detects something unusual, those signals are investigated by scientists and other vaccine surveillance systems, such as the Vaccine Safety Datalink, a collaboration between the CDC’s Immunization Safety Office and nine health care organizations, or the CDC’s Clinical Immunization Safety Assessment Project, a network of vaccine safety experts, including those at seven medical research centers, to evaluate causality. In the case of COVID-19 vaccines, VAERS is just one of several vaccine safety monitoring systems the government has in place. 

According to a November 2020 VAERS report, less than 15% of all the events reported to the database describe “serious events, such as hospitalizations, life-threatening illnesses, or deaths.” When a death is reported, the agency collects information, including medical records, autopsy reports and death certificates, and a qualified physician determines the cause of death.

“Just because somebody reports death doesn’t mean that the vaccine caused the death. So we don’t use VAERS to determine death rates or anything concerning death,” a CDC spokesperson told us previously

The vast majority of events reported for COVID-19 vaccines haven’t been serious. 

In the latest safety update presented by the CDC’s Vaccine Safety Team to the Advisory Committee on Immunization Practices on March 1, Dr. Tom Shimabukuro reported that as of Feb. 16, 94% of the reports submitted to VAERS after the administration of the Moderna and Pfizer/BioNTech vaccines were for non-serious events such as headaches, fever, chills and fatigue. The reports of serious events, such as anaphylaxis, heart attacks and strokes, were assessed by vaccine surveillance systems. Except for cases of anaphylaxis, which were rare, the CDC reported no safety concerns were detected, meaning there was no cause and effect relationship between the vaccines and the reported adverse events.  

“People die, unfortunately, without vaccination,” Orenstein told us. “The issue is to determine where the vaccine enhances that risk of death and not, and that’s why we have this very careful system.”

He said the fact that VAERS doesn’t determine causation is difficult for people to understand, despite all the disclaimers on its website and brochures. 

“There is a natural human tendency — plus it has served us well — if event B follows event A, then event A caused event B. I mean, we don’t need a scientific study to know if you jump out of a plane without a parachute, you’re going to be in trouble,” Orenstein said. “I think the issue here is the clinical syndromes that are occurring and [are being] reported to VAERS can also occur without a vaccine. And that’s what complicates things.”

Other VAERS Limitations

The fact that VAERS cannot assess causality is not its only weakness. 

“It’s the worst possible data that you could possibly imagine because there’s so many uncertainties about it,” said Ellenberg, who analyzed VAERS data for 11 years as director of the FDA’s Office of Biostatistics and Epidemiology in the Center for Biologics Evaluation and Research.

One of the major problems, she said, is that there’s no control group to study because unvaccinated people do not report adverse events to VAERS. Therefore, there’s no way to determine if the number of reported events is different from the number that would have been observed without vaccination. 

Take the 2,509 reports of death filed to VAERS as of March 29, which represent 0.0017% of those who had received a COVID-19 vaccine. People die every day for any number of reasons. In 2019, for example, 0.8% of the U.S. population died from any cause, according to the CDC. That was before the coronavirus pandemic. 

“You’re going to have deaths that had nothing to do with the vaccines,” Ellenberg told us. 

Deaths unrelated to COVID-19 occurred during the vaccine clinical trials, she said. So she expected to see deaths unrelated to the vaccines among the general population, especially considering that older people and people with underlying medical conditions are getting vaccinated first.

Another issue, Ellenberg said, is the accuracy and completeness of the data because anything that anybody reports goes into the database. A person could file a report omitting important details, such as which vaccine they got. Or someone could even report a false event, or report an event without having received a vaccine in the first place — although filing a false VAERS report intentionally is a violation of federal law punishable by fine and imprisonment.

“So you know, if somebody reports that they went skiing and broke their leg, and you know, two years before they had gotten a flu shot, they could report that to VAERS,” she said. 

As experts have told us before, reports to VAERS tend to increase when there’s more awareness of the vaccine or more publicity around specific side effects. For example, Ellenberg said, there was an increase in the number of VAERS reports following approval of a Lyme disease vaccine in the late 1990s and a class-action lawsuit against the vaccine manufacturer, which withdrew the vaccine from the market even though “the adverse event rate was not shown to be elevated among vaccine recipients,” according to the National Institute of Allergy and Infectious Diseases. 

VAERS data aren’t meant to allow safety comparisons between vaccines, but multiple social media posts make such false comparisons anyway. As a disclaimer on the VAERS website states: “The number of reports alone cannot be interpreted or used to reach conclusions about the existence, severity, frequency, or rates of problems associated with vaccines.”

Other limitations include underreporting, when people don’t report serious events happening after vaccines.

“In addition, it is often the case that more than one vaccine was administered, making it difficult to know to which of the vaccines the event might be attributed,” the VAERS user guide says.

Experts agree that even with all of VAERS’ weaknesses, having a system with the potential for identifying new adverse effects and signals that can be followed up with more data is still worth having. That’s especially true in cases when an emergency use authorization has been issued, and there has been less time to monitor possible adverse events before a vaccine gets on the market. 

Because of the urgency of the ongoing pandemic, the FDA required at least two months of follow-up data on half or more of the participants in phase 3 clinical trials for a COVID-19 vaccine to get an emergency use authorization. As we’ve explained, full licensure requires a minimum of six months, though experts say there’s little reason to think more time would uncover safety concerns.

“There are people who have said VAERS, and those kinds of systems are worthless, we shouldn’t even bother with them,” Ellenberg said. “I don’t agree with that.”

Update, May 14: After investigating 15 cases of a rare clotting condition out of nearly 8 million Johnson & Johnson vaccinations, the CDC and Food and Drug Administration are warning of a suggested increased risk of the dangerous condition, which occurred in women and resulted in three deaths as of April 21. The CDC says “women younger than 50 years old especially should be aware of the rare risk of blood clots with low platelets after vaccination, and that other COVID-19 vaccines are available where this risk has not been seen.” As of May 11, 28 cases had been identified out of more than 9 million J&J vaccines administered. For more, see “Q&A on the Rare Clotting Events That Caused the J&J Pause.” 

Editor’s note: SciCheck’s COVID-19/Vaccination Project is made possible by a grant from the Robert Wood Johnson Foundation. The foundation has no control over our editorial decisions, and the views expressed in our articles do not necessarily reflect the views of the foundation. The goal of the project is to increase exposure to accurate information about COVID-19 and vaccines, while decreasing the impact of misinformation.

Sources

COVID Data Tracker.” Centers for Disease Control and Prevention website. Last updated 29 Mar 2021, accessed 30 Mar 2021. 

Shimabukuro, Tom. “COVID-19 vaccine safety update.” Powerpoint slides for Advisory Committee on Immunization Practices meeting. 1 Mar 2021.

Guide to Interpreting VAERS Data.” Vaccine Adverse Event Reporting System website. Accessed 30 Mar 2021. 

McDonald, Jessica. “Instagram Post Makes Invalid Comparison Between COVID-19 and Flu Vaccines.” FactCheck.org. 19 Feb 2021.

Gore, D’Angelo. “Hagler’s Widow Refutes Rumors About How He Died.” FactCheck.org. 17 Mar 2021.

Jaramillo, Catalina. “No Evidence Vaccines Impact Fertility.” FactCheck.org. 26 Feb 2021.

VAERS Data.” VAERS website. Accessed 30 Mar 2021. 

Frequently Asked Questions (FAQs).” VAERS website. Accessed 30 Mar 2021. 

Selected Adverse Events Reported after COVID-19 Vaccination.” CDC website. Last updated 22 Mar 2021, accessed 26 Mar 2021. 

Vaccine Adverse Event Reporting System. “VAERS Data Use Guide.” Last updated Nov. 2020, accessed 30 Mar 2021. 

Vaccine Safety.CDC website. Last updated 9 Sep 2020, accessed 30 Mar 2021. 

About VAERS.” VAERS website. Accessed 30 Mar 2021. 

Vaccine Adverse Event Reporting System. “VAERS Table of Reportable Events Following Vaccination.” Accessed 30 Mar 2021.

Centers for Disease Control and Prevention. “Intussusception among recipients of rotavirus vaccine–United States, 1998-1999.” MMWR Morb Mortal Wkly Rep.;48(27):577-81. 16 Jul 1999.

Centers for Disease Control and Prevention. “Withdrawal of rotavirus vaccine recommendation.” MMWR Morb Mortal Wkly Rep.;48(43):1007.5 Nov 1999. 

Shimabukuro, Tom T., et al. “Safety monitoring in the Vaccine Adverse Event Reporting System (VAERS).” Vaccine; 33(36): 4398-4405. 26 Aug 2015.

Febrile Seizures and Childhood Vaccines.” CDC website. Last updated 14 Aug 2020, accessed 30 Mar 2021. 

COVID-19 Vaccine Reporting Systems.” CDC website. Last updated 27 Feb 2021, accessed 30 Mar 2021. 

COVID-19 Vaccine Safety Surveillance.” U.S. Food and Drug Administration website. Last updated 9 Feb 2021, accessed 30 Mar 2021. 

Ellenberg, Susan, and Robert T. Chen. “The complicated task of monitoring vaccine safety.” Public Health Reports 112(1):10-20; discussion 21. Nov 1996. 

Death and Mortality.” CDC website. Last Updated 1 Mar 2021, accessed 28 Mar 2021. 

FDA Briefing Document Moderna COVID-19 Vaccine.” Vaccines and Related Biological Products Advisory Committee Meeting. 17 Dec 2020. 

FDA Briefing Document Pfizer-BioNTech COVID-19 Vaccine.” Vaccines and Related Biological Products Advisory Committee Meeting. 10 Dec 2020.

FDA Briefing Document Johnson & Johnson COVID-19 Vaccine.” Vaccines and Related Biological Products Advisory Committee Meeting. 26 Feb 2021.

Report an Adverse Event to VAERS.” VAERS website. Accessed 30 Mar 2021. 

Lathrop, Sarah L., et al. “Adverse event reports following vaccination for Lyme disease: December 1998-July 2000.” Vaccine; 20(11-12):1603-8. 22 Feb 2002.

Nigrovic, L. E.; and K. M. Thompson. “The Lyme vaccine: a cautionary tale.” Epidemiology & Infection; 135(1): -8. Jan 2007.

Ellenberg, Susan. Professor of biostatistics, medical ethics and health policy at the University of Pennsylvania’s Perelman School of Medicine. Phone interview with FactCheck.org. 26 Mar 2021.

Orenstein, Walter. Associate director of the Emory Vaccine Center. Phone interview with FactCheck.org. 2 Mar 2021.