The icterus/jaundice is usually from lysis/breakdown of infected red blood cells as they rupture and release new malaria parasites into the bloodstream.  If only 1% of red cells are infected, this will be mild.  If “parasitaemia” is severe/life threatening, say, 10% of red cells infected, then the jaundice will be dramatic as well as a risk for catastrophic organ failure from cell breakdown, iron deposition into capillaries/small blood vessels in brain/kidneys/liver. In such cases, exchange blood transfusion could be life-saving.