The patches vary in size and can cross veins. The leaf surface is usually rougher than normal. Edges of infected leaflets may be slightly crinkled or wavy. Infected leaves usually look shiny. The stems of the plant bend outward, giving the plants an open look.
Tubers are usually unaffected, except for a slight decrease in size.
In temperate regions, the only host is potato, although there are other hosts in more tropical climates. This disease was not discovered until the early 1950's because the symptoms are very inconspicuous. The disease may cause a slight decrease in yield. It is transmitted by aphids in a non-persistent manner. Some strains of this virus are transmitted only by planting infected tubers.