PRB4 and infection: Two factors contribute for this situation: at the end of the hepatic cycle, each ruptured hepatocyte releases approximately 2,000 merozoites when the infection is due to Pm and 10,000 when due to Pv, whereas ~40,000 merozoites/hepatocyte are released when the infection is due to Pf. Moreover, Pm only invades old red blood cells (0.1% of the total) and Pv/Po preferentially invade young red blood cells (1% of the total), whereas Pf invades red blood cells in any developmental stage (Kerlin and Gatton, 2013).