Monday, May 3, 2021

Misuse of CDC data on vaccine side-effects fuels unjustified fears of COVID vaccination

Some resistance to getting the COVID vaccine is driven by terrifying, but mostly deceptive and inaccurate rumors, spread on social media.

First, the good news: The Pfizer and Moderna vaccines have been relatively problem free aside from some temporary side effects that many people experience. According to a report from the Centers for Disease Control and Prevention (CDC), the Pfizer and Moderna vaccines have been highly effective among vaccinated seniors 65 and older.

“In a multistate network of U.S. hospitals during January–March 2021, receipt of Pfizer-BioNTech or Moderna COVID-19 vaccines was 94% effective against COVID-19 hospitalization among fully vaccinated adults and 64% effective among partially vaccinated adults aged ≥65 years.”

This is from the Associated Press: "COVID-19 hospitalizations tumble among US senior citizens" by Matthew Perrone and Carla K. Johnson, 4/22/21.

"WASHINGTON (AP) — COVID-19 hospitalizations among older Americans have plunged more than 70% since the start of the year, and deaths among them appear to have tumbled as well, dramatic evidence the vaccination campaign is working. Now the trick is to get more of the nation’s younger people to roll up their sleeves.

"The drop-off in severe cases among Americans 65 and older is especially encouraging because senior citizens have accounted for about 8 out of 10 deaths from the virus since it hit the U.S., where the toll stands at about 570,000"

Reports of outbreaks among vaccinated people are not surprising. The vaccines were determined to be about 95% effective, meaning that for one out of 20 vaccinated people, the vaccine does not give full protection against the virus. When there is extensive community spread, as there is in Michigan, until the infection rate goes down, there is still a significant risk of contracting or spreading the disease. It is wise to remain cautious, wearing masks where it is not possible to social distance, and avoiding large gatherings, especially at indoor events.

One source of horror stories about vaccine side effects comes from misinterpretation and misapplication of data from VAERS, the CDC Vaccine Adverse Event Reporting System.  

From the CDC Website: “Established in 1990, the Vaccine Adverse Event Reporting System (VAERS) is a national early warning system to detect possible safety problems in U.S. licensed vaccines. VAERS is co-managed by the Centers for Disease Control and Prevention (CDC) and the U.S. Food and Drug Administration (FDA). VAERS is a post-marketing safety surveillance program, collecting information about adverse events (possible side effects) that occur after the administration of U.S. licensed vaccines. This online database provides a nationwide mechanism by which VAERS reports are made available to the public and may be reviewed and analyzed…”

No specific conclusions can be drawn from the VAERS reports on whether the COVID vaccines actually caused the reported side effects. The CDC issues a strongly worded DISCLAIMER to prevent it being used to prove causation:  

"VAERS accepts reports of adverse events and reactions that occur following vaccination. Healthcare providers, vaccine manufacturers, and the public can submit reports to VAERS. While very important in monitoring vaccine safety, VAERS reports alone cannot be used to determine if a vaccine caused or contributed to an adverse event or illness. The reports may contain information that is incomplete, inaccurate, coincidental, or unverifiable. Most reports to VAERS are voluntary, which means they are subject to biases. This creates specific limitations on how the data can be used scientifically. Data from VAERS reports should always be interpreted with these limitations in mind. [Emphasis added]

"The strengths of VAERS are that it is national in scope and can quickly provide an early warning of a safety problem with a vaccine. As part of CDC and FDA's multi-system approach to post-licensure vaccine safety monitoring, VAERS is designed to rapidly detect unusual or unexpected patterns of adverse events, also known as 'safety signals.' If a safety signal is found in VAERS, further studies can be done in safety systems such as the CDC's Vaccine Safety Datalink (VSD) or the Clinical Immunization Safety Assessment (CISA) project. These systems do not have the same limitations as VAERS, and can better assess health risks and possible connections between adverse events and a vaccine."

These are additional warnings on the limitations of VAERS data:

Review the limitations and interpret VAERS data with caution:

The data are unverified reports of health events, both minor and serious, that occur after vaccination.

•VAERS data are from a passive surveillance system. Such data are subject to limitations of under-reporting, reporting bias, and lack of incidence rates in unvaccinated comparison groups.
• Reports show the simultaneous administration of multiple vaccines (making it difficult to know to which of the vaccines, if any, the event might be attributed).
• VAERS occasionally receives case reports from U.S. manufacturers that were reported to their foreign subsidiaries. Under FDA regulations, if a manufacturer is notified of a foreign case report that describes an event that is both serious and unexpected (in other words, it does not appear in the product labeling), they are required to submit it to VAERS. These case reports are of variable data quality and completeness, due to the differences in country reporting practices.
• In some media reports and on some web sites on the Internet, VAERS reports are presented as verified cases of vaccine deaths and injuries. Statements such as these misrepresent the nature of VAERS. [Emphasis added]
• Establishing causal relationships between vaccines and adverse events requires additional scientific investigation. The CDC and FDA take into account the complex factors mentioned above, and others, when monitoring vaccine safety and analyzing VAERS reports.
• VAERS staff at CDC and FDA follow up on all serious adverse event reports to obtain additional medical, laboratory, death certificates, and/or autopsy records to help understand the circumstances. However, VAERS public data do not generally change based on the information obtained during the follow-up process.
• See also the Disclaimer at Summary above. 

When you read assertions on social media that the COVID vaccines have caused thousands of deaths and injuries, the source may have inadvertently or deliberately distorted information from VAERS.

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