The formation of blood clots is a natural and important process that prevents us from bleeding to death. However, clots can sometimes form inside of healthy blood vessels at great risk to the body. This is currently being reported, although not confirmed, to be associated with the AstraZeneca Covid-19 vaccine. ThePrint’s Sandhya Ramesh explains how blood clotting works and what the emerging vaccine-induced prothrombotic immune thrombocytopenia (VIPIT) is.