Seems to be carried by beet leafhopper. Main symptoms are curling and twisting of leaves of affected plants. Prevention is planting at times that may avoid high leafhopper populations, or excluding insects with row covers. Common mosaic, tobacco mosaic, Aucuba mosaic and cucumber mosaic can all infect tomatoes. Mottles areas of light and dark green on leaves, sometimes appearing puckered, or malformation of leaflets, or yellow mottling of leaves, or stunted yellow, bushy plants can be seen with these diseases.
Aphids can transmit mosaic viruses.
Seedlings can be dipped or sprayed with milk at least twice if they are suspected of being infected.