VAERS and AE reporting

Adverse Event Reporting Programs

Many countries have tools to collect reports of adverse events following vaccination. VAERS (or Vaccine Adverse Event Reporting System) is the American system run by the CDC. Similar systems around the world include AEFI or Adverse Events Following Immunization (Canada), Yellow Card scheme (UK), EudraVigilance (UK), and VigiBase/VigiAccess (WHO).

What is Adverse Event Reporting?

The primary objectives of these systems are to identify adverse events (AE) that might be associated with vaccination that were not detected in clinical trials (for example, because they are too rare).

The reports themselves do not imply any causal link between the adverse event and the vaccine. Healthcare providers are encouraged to submit any adverse events that occur after vaccination, whether or not they suspect any relationship. Specific to COVID vaccines - reporting is MANDATORY for serious AE.

A proper analysis of AE data incorporates background rates of the reported events and any known reporting biases. The objective is to identify safety signals - events that seem to occur more often following vaccination than would otherwise be expected - for further study.

Myocarditis is an example of an adverse event that was too rare to capture in clinical trials, but was identified as a possible safety signal early in the vaccination campaign thanks in part to AE reporting. See: Misinformation about Myocarditis

Question: Why is the VAERS report volume so high?

Reports to VAERS have increased dramatically for COVID-19 vaccines. There are several reasons:

1. Healthcare providers are required to report ALL serious adverse events following COVID-19 vaccination. This is not the case for other vaccines. (https://vaers.hhs.gov/faq.html)
2. Other than influenza vaccination, COVID-19 vaccines are the only vaccines to be administered to the entire population, including elderly individuals who are prone to health problems.
3. Due to the pandemic, the rapid development and approval of the vaccines, and the large scale and rapid distribution, there is heightened concern about vaccine safety, leading to the largest post-vaccination followup effort in world history.

Claim: Adverse events are side-effects!

No. It is not typically possible to definitively establish a causal association between an adverse event and a vaccine. This is why AE reporting systems are needed - to collect information about all adverse events, then analyze the data statistically to determine if a causal link is probable.

Most serious adverse events are NOT associated with vaccination. Randomized control trial data from the vaccines shows that serious adverse events occur at almost identical rates between the vaccine and the placebo control. This makes it highly improbable that the vaccine causes any serious adverse events at a level that could be detected in a Phase 3 trial with over 44,000 participants (see page 15: https://www.fda.gov/media/151707/download )

While it's easy to estimate the probability of serious adverse events after a randomized control trial, post-authorization/approval systems like VAERS don't have a control group, so it is far more challenging to make accurate judgements because the reporting rate cannot be ascertained with certainty.

Claim: VAERS shows over 20,000 deaths due to vaccines!

There are more than 20,000 reports with an outcome of death, but this figure vastly underreports the normal background death that we would expect in the vaccinated population - roughly 7000 per day in the United States.

Claim: Only 1% of adverse events get reported, so the actual number is much higher!

The reporting rate is influenced by a variety of factors, including...

1. the seriousness of the event (events with an outcome of death are more likely to be reported than reports of arm soreness),
2. the proximity to vaccination (events occurring shortly after vaccination are more likely to be reported compared to events long after vaccination),
3. the perceived probabilty of association (cardiac issues are more likely to be reported than murder),
4. the general level of concern about vaccine adverse events (which is heightened in a mass vaccination campaign during a pandemic).

1% is not a reasonable estimate of the reporting rate for serious adverse events shortly after vaccination, though it is true that many events are unreported, otherwise we should expect to have millions of deaths just to account for normal rates of death!

An unknown number of VAERS reports are completely fake

Some obviously so: https://docs.google.com/spreadsheets/u/0/d/1cM7y0QMfgRDJgF7REMV3LgAoR6Bm4s-vOKkSx3T5MhE/htmlview

Important! Fake reports are removed from VAERS as they are identified, so this is a relatively weak argument. The vast majority of reports to VAERS are probably legitimate, but this does not mean that the reported adverse event has any causal association with vaccination. Most do not.