VAERS reports of adverse events in people who received COVID-19 vaccines don’t demonstrate that these events were caused by the vaccines; evidence does not indicate COVID-19 vaccines caused Bell’s palsy and deaths

“Thousands of COVID Vaccine Injuries and 13 U.S. Deaths Reported in December Alone”; “In December, 3,916 COVID vaccine-related adverse events, including 13 deaths, were reported to VAERS”
Inadequate support: The 3,916 adverse events attributed to the COVID-19 vaccines are based on the number of reports made in the U.S. Vaccine Adverse Events Reporting System (VAERS). However, while VAERS records adverse events occurring after vaccination, reports don’t demonstrate causal relationships between a vaccine and adverse events.
Misleading: The article cites instances of adverse events like Bell’s palsy and death occurring post-vaccination as “vaccine injuries”, implying that the COVID-19 vaccines caused these events (the post hoc ergo propter hoc fallacy). However, simply because an event occurred after vaccination does not mean that vaccination caused the event. Furthermore, some of the events cited were unrelated to the vaccine or were of dubious origin.
Both COVID-19 vaccines approved for emergency use by the U.S. Food and Drug Administration were thoroughly reviewed for safety and efficacy before approval. The U.S. Vaccine Adverse Events Reporting System (VAERS) enables the public and healthcare providers to report adverse events that occur after they received a vaccine. While VAERS serves as an early warning system for potential problems with vaccines, determining whether there is a causal link requires further investigation into these reports. VAERS data only tells us that an adverse event might have occurred after vaccination; on its own it cannot prove that vaccines caused the adverse event.

FULL CLAIM: “Thousands of COVID Vaccine Injuries and 13 U.S. Deaths Reported in December Alone”; “In December, 3,916 COVID vaccine-related adverse events, including 13 deaths, were reported to VAERS”


An article published in mid-January 2021 by Children’s Health Defense, an organization that opposes vaccines, claimed that thousands of adverse events related to the COVID-19 vaccine, including deaths, were reported in December 2020. The organization based this claim on data from the U.S. Vaccine Adverse Events Reporting System (VAERS). The article received more than 15,000 interactions on Facebook and more than 6,000 shares in less than a week, according to social media analytics tool CrowdTangle.

VAERS provides the general public and healthcare workers with an avenue to report adverse events occurring in people after they were vaccinated. The system is co-managed by the U.S. Centers for Disease Control and Prevention (CDC) and the U.S. Food and Drug Administration (FDA). It serves as “a national early warning system to detect possible safety problems in U.S.-licensed vaccines”, which “can provide CDC and FDA with valuable information that additional work and evaluation is necessary to further assess a possible safety concern.”

As we explain below, the article is inaccurate and misleading in its use of VAERS data.

VAERS reports alone don’t demonstrate a causal relationship between a vaccine and an adverse event; COVID-19 vaccines found to be generally safe

The term “adverse event” describes any health problem that occurs in a person after they received a vaccine, regardless of whether the event was caused by a vaccine. For example, deaths by road traffic accidents are also listed in VAERS as adverse events, but are obviously not caused by the vaccine. In fact, VAERS even accepts reports about someone who turns into the Hulk, a Marvel Comics character, after vaccination.

Citing VAERS reports as evidence that vaccines are harmful is a common feature of vaccine misinformation. Health Feedback previously reviewed claims that were based on VAERS reports and found them to be inaccurate or unsupported. The article by Children’s Health Defense claimed that “In December, 3,916 COVID vaccine-related adverse events, including 13 deaths, were reported to VAERS”. By labeling these adverse events as “vaccine-related”, the article implies that all reports of adverse events were caused by the vaccine.

However, VAERS makes it clear that its data is not meant to demonstrate a causal relationship between an adverse event and a vaccine:

A report to VAERS generally does not prove that the identified vaccine(s) caused the adverse event described. It only confirms that the reported event occurred sometime after [the] vaccine was given. No proof that the event was caused by the vaccine is required in order for VAERS to accept the report. VAERS accepts all reports without judging whether the event was caused by the vaccine.

In other words, VAERS collects information about adverse events occurring following vaccination. But simply because one event followed another event does not mean that the two events are causally linked to each other (also known as the post hoc ergo propter hoc fallacy). One common example used to illustrate this fallacy is “the rooster crows just before the sun rises, therefore the rooster’s crow causes the sun to rise”.

Therefore, the article’s use of VAERS reports is incorrect and its claim that VAERS data show there have been “thousands of COVID Vaccine Injuries” is unsupported and misleading.

So far, two COVID-19 vaccines have been approved for emergency use by the FDA, one developed by Pfizer and BioNTech and the other by Moderna. In order to receive approval for emergency use, the makers of both vaccines had to submit data on safety and efficacy collected during clinical trials to the FDA for review, to ensure the vaccines are effective. This process is rigorous and transparent, and the findings of the clinical trials and FDA review are accessible to the public (see full reports for the Pfizer-BioNTech and Moderna vaccines).

In the case of both COVID-19 vaccines, the FDA concluded that they met the necessary criteria for safety and efficacy. Preliminary data from clinical trials indicate that both vaccines have more than 94% efficacy in protecting vaccinated individuals from the disease. Clinical trials are still underway, so estimates of each vaccine’s efficacy may change.

Like any medicine or medical procedure, vaccines can also cause side effects in some vaccinated individuals. Some of the common side effects of the COVID-19 vaccines approved for emergency use by the FDA are pain at the injection site, fever, headache, and fatigue. However, these side effects are mild and short-lived compared to the risks associated with natural infection, such as long-term effects of COVID-19 and death.

Curiously, although the article uses VAERS reports to support its claim, at the same time it also claims VAERS has an “abysmal track record […] in capturing serious adverse events”. However, as Vaxopedia pointed out, VAERS reports were key to helping the CDC and FDA recognize that a vaccine against rotavirus caused an increased risk of intussusception, which is a potentially life-threatening medical condition where an individual’s intestine becomes obstructed.

Following the discovery of this risk of intussusception, the Advisory Committee on Immunization Practices, American Academy of Pediatrics and the American Academy of Family Physicians recommended that the vaccine should not be used. In keeping with this recommendation, the vaccine is no longer available for use in the U.S. This is a testament to the emphasis placed on vaccine safety by public health authorities in the U.S and to the utility of VAERS.

The article inaccurately attributes adverse events like Bell’s palsy and death to COVID-19 vaccines

The article labels many adverse events occurring after COVID-19 vaccination, ranging from allergic reactions, Bell’s palsy, and death, as “vaccine injuries” and “mRNA vaccine side effects”. The overall effect may leave readers with the message that the COVID-19 vaccines are responsible for many adverse events and are therefore unsafe.

However, of the adverse events that have been reported so far, only severe allergic reactions, also known as anaphylaxis, have been causally associated with the COVID-19 vaccines. For this reason, the CDC recommends that people with a history of anaphylaxis should not receive the currently available mRNA vaccines.

Events such as Bell’s palsy and death were indeed reported during vaccine clinical trials, notably for the Pfizer-BioNTech vaccine, which led to viral misinformation claiming that the vaccine caused such events. Health Feedback previously reviewed this claim and found it to be unsupported by evidence.

From its review of safety data for the Pfizer-BioNTech vaccine, the FDA concluded that the “observed frequency of reported Bell’s palsy is consistent with the expected background rate in the general population,” and that, “All deaths represent events that occur in the general population of the age groups where they occurred, at a similar rate”.

In other words, both deaths and cases of Bell’s palsy observed during the trial occurred at a frequency consistent with that expected in an unvaccinated population. Because the number of participants included in the trial was very large—with more than 20,000 people each in the vaccine and placebo group—a certain number of deaths and Bell’s palsy were expected to occur solely based on the background rate, with or without the vaccine.

Since the frequency of these events was not higher than expected, the evidence so far does not indicate that the COVID-19 vaccine caused these events. Rather, it is likely that these events occurred by chance after the vaccine was administered.

However, Nina Shapiro, professor of head and neck surgery at the David Geffen School of Medicine at University of California Los Angeles, also cautioned that “it’s very early in the vaccine roll-out to the non-study-trial population”, so more data will still be needed to rule out a causal relationship between Bell’s palsy and the vaccine. The FDA also stated that it would continue to monitor cases of Bell’s palsy in people who received the vaccine.

Indeed, the occurrence of incidental illnesses and deaths, which would be expected to occur in a population regardless of whether vaccines are administered, is a source of concern to experts, as seen in this commentary in Science Translational Medicine and this article by STAT News. Given that these incidental illnesses and deaths can be viewed as side effects of the COVID-19 vaccine, rather than simply a product of coincidence, these events can become the springboard for vaccine misinformation.

Some accounts of the alleged side effects reported in the article were already debunked. For example, an autopsy revealed that the death of Portuguese nurse Sonia Azevedo was unrelated to the vaccine, as reported in this Health Feedback review. And the account of a registered nurse in Tennessee who claimed to have developed Bell’s palsy following COVID-19 vaccination is of dubious origin, as investigations by Snopes and Associated Press found that the Tennessee Department of Health has no record of a registered nurse with her name.


The COVID-19 vaccines approved for emergency use in the U.S. were reviewed by the FDA to ensure their safety and efficacy before approval. The vaccines demonstrated a high efficacy in protecting people from COVID-19 and are generally safe, although like any medicine or medical procedure, they cause some side effects, such as pain at the injection site, fever and fatigue. These side effects are mild, short-lived, and safer compared to natural infection with the virus that causes COVID-19. The benefits of these vaccines outweigh their risks.

By enabling populations to achieve herd immunity, vaccines help us progress towards an end to the pandemic. As Florian Krammer, a professor of vaccinology at Icahn School of Medicine at Mount Sinai, stated in this Nature article: “Right now, we need a vaccine that works,” even if the vaccine only works for a few months or doesn’t stop transmission. “That’s what we need in order to get half-way back to normal.


The fact-checking organization Faktisk, which is based in Norway, published a fact-check regarding news reports of deaths among the elderly after COVID-19 vaccination in Norway, which went viral on social media. Faktisk explained that it is still too early to conclude that the deaths were caused by the vaccination. The Norwegian Medicines Agency also clarified that “We will not give any general advice against taking the vaccines due to these reports of deaths in Norway”.


Published on: 19 Jan 2021 | Editor:

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