Mosaic disease affects cassava and tobacco. It is a viral disease that causes a mosaic-like pattern on the leaves of infected plants. The affected leaves usually become distorted, stunted and mottled with light and dark green patches. The virus is transmitted by insects, such as whiteflies and aphids, and also through the use of infected plant materials for propagation. The disease can cause significant yield losses in affected crops, and control measures such as the use of resistant varieties and insecticides are often recommended.