As the other rude guy said-the vaccine causes your cells to make the spike protein to teach your body to ID said protein and form a defense against it. But we've since found out that cells far from the injection site end up making these proteins, which causes cell death, blood clotting (as part of internal healing) that has traveled to the brain and other organs causing death (strokes, etc.). Men are especially hard hit. The first guy to get the Pfizer vax in the UK died recently of a stroke.