evidence: The active ingredients in both the Pfizer-BioNTech and Moderna COVID-19 vaccines consist of messenger RNA molecules (mRNA) that encode the spike protein of SARS-CoV-2 (the coronavirus that causes COVID-19). Once injected into a patient, the modified mRNA enters the muscle cells whereby it is translated into the SARS-CoV-2 viral spike protein (S). Alone, the viral spike protein (a protein found on the surface of the virus) cannot cause COVID-19 as it is incapable of triggering the multi-step process that leads to the replication (multiplication) and spread of the virus. However, this spike protein can be identified by the immune system as a foreign object and triggers the activation of the immune system. This trigger makes a person better prepared to fight COVID-19 when exposure to the actual virus occurs. [...] The Pfizer-BioNTech COVID-19 vaccine consists of a frozen suspension of nucleoside-modified messenger RNA (modRNA) and the following inactive ingredients: [...] The Pfizer-BioNTech COVID-19 vaccine is manufactured and transported as frozen vials of white to off-white sterile and preservative-free suspension kept frozen at -80°C to -60°C. Before use, each vial is is resuspended/diluted with 1.8 mL of sterile 0.9% Sodium Chloride Injection, USP. The solution obtained corresponds to 5 vaccine doses of 0.3 mL each and can be stored at 2°C to 25°C for up to 6 hours. The vaccine is administered intramuscularly as two 0.3 mL (30 ug) injections separated by 21 days.