BNT162b2 vaccine against Covid-19 is composed of an RNA having 4284 nucleotides, divided into 6 sections, which bring the information to create a factory of S Spike proteins, the ones used by Sars-CoV-2 (Covid-19) to infect the host. After that, these proteins are directed outside the cell, triggering the immune reaction and antibody production.The problem is the heavy alteration of the mRNA: Uracil is replaced to fool the immune system with Ψ (Pseudouridine); the letters of all codon triplets are replaced by a C or a G, to extremely increase the speed of protein synthesis; replacement of some amino acids with Proline; addition of a sequence (3'-UTR) with unknown alteration. These impairments could cause strong doubts about the presence of codon usage errors. An eventual mistranslation has consequences on the pathophysiology of a variety of diseases.In addition, mRNA injected is a pre-mRNA, which can lead to the multiple mature mRNAs; these are alternative splicing anomalies, direct source of serious long-term harm on the human health.In essence, what will be created may not be identical with protein S Spike: just an error in translational decoding, codons misreading, production of different amino acids, then proteins, to cause serious long-term damage to human health, despite the DNA is not modified, being instead in the cell nucleus and not in the cytoplasm, where the modified mRNA arrives.However, in this case, the correlation between speed of synthesis and protein expression with synthesis errors, as well as the mechanism that could affect the translation of the sequence remain obscure, many trials have not yet been performed.