evidence: The U.S. has three approved COVID-19 vaccines; however, the two that are most often used based on the current vaccine recommendations are those described as "mRNA vaccines." Find out more about each vaccine: [...] Even though the COVID-19 vaccines were initially released under Emergency Use Authorization (EUA), they were still approved by the Food and Drug Administration (FDA). The review process was the same, but because of the pandemic, the data could be submitted after a shorter period of participant follow-up than usual. However, even after submitting data (and getting an EUA), those studies continued. [...] The COVID-19 vaccines available in the U.S. do not contain any blood products, including red blood cells, white blood cells or platelets.