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What do we know about the toxicity of spike proteins made from COVID-19 vaccines?

This article was published on
June 4, 2021

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The spike proteins from mRNA vaccines are not known to harm our bodies. Vaccines go through very rigorous standards set by the U.S. FDA to meet safety and efficacy criteria. Thousands of people underwent clinical trials over several months to understand if there were any side effects or risks associated with the vaccines. The vaccines are still being monitored for any safety concerns or patterns that could risk human well-being.  So far, there is no scientific evidence available that suggests that spike proteins created in our bodies from the COVID-19 vaccines are toxic or damaging organs of our body, as is being claimed on some social platforms.

The spike proteins from mRNA vaccines are not known to harm our bodies. Vaccines go through very rigorous standards set by the U.S. FDA to meet safety and efficacy criteria. Thousands of people underwent clinical trials over several months to understand if there were any side effects or risks associated with the vaccines. The vaccines are still being monitored for any safety concerns or patterns that could risk human well-being.  So far, there is no scientific evidence available that suggests that spike proteins created in our bodies from the COVID-19 vaccines are toxic or damaging organs of our body, as is being claimed on some social platforms.

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What our experts say

The spike proteins from mRNA vaccines are not known to harm our bodies. Vaccines go through very rigorous standards set by the U.S. FDA to meet safety and efficacy criteria. Thousands of people underwent clinical trials over several months to understand if there were any side effects or risks associated with the vaccines. The vaccines are still being monitored for any safety concerns or patterns being seen that can risk human well-being. 

So far, there is no scientific evidence available that suggests that spike proteins created in our bodies from the COVID-19 vaccines are toxic or damaging our organs. COVID-19 vaccines are relatively new and long-term side effects are yet to be known. However, the vaccines have met the safety standards of many government and international safety agencies.

Several systems help us monitor vaccine safety. In the United States these include the Vaccine Adverse Event Reporting System (VAERS), The Vaccine Safety Datalink (VSD), the Post-License Rapid Immunization Safety Monitoring (PRISM), and the Clinical Immunization Safety Assessment Project (CISA). These systems are used by scientists to monitor side effects and any other patterns of risks from vaccines.

The COVID-19 vaccine has been administered to 135 million people in the United States. As expected with any vaccine, some fully vaccinated people still got sick, hospitalized, and/or died. These "breakthrough cases" are a very small percentage of those vaccinated (<0.001%) and are being studied to detect any relevant patterns.

So far no scientific evidence is available that gives credence to claims that spike proteins created from vaccines travel in our bloodstreams. Research shows that spike proteins stay stuck to the surface of the cells around the vaccine's injection site. They are not known to wander around to other parts of the body.

A very tiny dose of the vaccine does make it to the bloodstream (about 1%), but as soon as it gets to the liver, the enzymes there destroy it completely. The U.S. CDC refers to the spike protein made from the vaccine as “harmless.”

Context and background

Vaccine development, approval, and manufacturing involve rigorous processes, first among which is safety. Only if a vaccine is considered safe and effective, and the benefits outweigh the risks, is a vaccine authorized for use. Several scientists and experts at regulatory agencies like the FDA study vaccine data, and come to conclusions on vaccine safety and efficacy before deciding whether it's safe for the public to use. 

Resources

  1. mRNA Vaccines  (U.S. CDC)
  2. Spike Protein (Science Direct)
  3. Explainer: What is a spike protein? (Science News for students)
  4. Spike Protein/ S Protein (SinoBiological)
  5. Structure, Function, and Antigenicity of the SARS-CoV-2 Spike Glycoprotein (Cell)
  6. Development and Licensure of Vaccines to Prevent COVID-19 - Guidance for Industry (US FDA)
  7. Spike Protein Behavior (Science Translational Medicine)
  8. Possibility of COVID-19 Illness After Vaccination (U.S. CDC)
  9. COVID-19 Breakthrough Case Investigations and Reporting (U.S. CDC)
  10. Ensuring the Safety of Vaccines in the United States (U.S. CDC)
  11. Ensuring the Safety of Vaccines in the United States (US FDA)
  12. Vaccine Safety Monitoring (US CDC)
  13. Vaccine Safety Basics (WHO)

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