Several species of aphid transmit the virus including the plum-thistle aphid ("Brachycaudus cardui"), the plum leaf curl aphid ("Brachycaudus helichrysi") and the green peach aphid ("Myzus persicae"). Winged aphids can transmit plum pox within an orchard, and over short distances (200–300 meters) to trees in nearby orchards. Unlike some other viruses, like barley yellow dwarf virus, PPV is not persistent in the aphid and is transferred from the mouthparts of the aphid between plants. Long distance spread usually occurs as a result of the movement of infected nursery stock or propagative materials. Once a plant is infected the virus is systemic and occurs in the cytoplasm of cells from all parts of the plant.