The covid mRNA vaccines do the same thing that the wild viruses do. But instead of generating the entire virus they build only a portion, the spike protein. Your immune system learns it, and builds antibodies to destroy it.
__
But the spike protein itself is toxic. The spike is what makes the SARS-CoV-2 lethal to humans (Severe Acute Respiratory Syndrome), most likely the result of bioengineering at the Wuhan Institute of Virology.
The experimental Covid-19 “vaccine” induces the body to produce billions of spikes that circulate throughout the body including past the blood-brain barrier, causing inflammation, blood clots and a progressively weakened immune system.
The mRNA-based treatments cannot keep up with the mutation rate of the spike, creating a condition known as Antibody Dependent Enhancement (ADE), increasing the likelihood of being infected and in many cases, increasing the severity of the infection.
A little bit of knowledge is a dangerous thing.
ADE and ERD occurred with whole virus vaccine attempts for SARS-1 and MERS, which is probably a major reason that no whole virus vaccines were attempted here for SARS-2.
“But the spike protein itself is toxic.”
In that case everyone who ever caught Covid is in big trouble. But there’s no evidence that the spike protein itself is “toxic”. The closest thing to that is VITT, a very rare occurrence seen with Astra-Zeneca and J&J vaccines but not Moderna or Pfizer.
https://www.uptodate.com/contents/covid-19-vaccine-induced-immune-thrombotic-thrombocytopenia-vitt