Diseases may affect from other papaya-growing areas, is less afflicted with disease problems than Florida and Puerto Rico, but still has to combat a number of major and minor maladies. Most serious of all is the mosaic virus, on plant and fruit, which is common in Florida, Cuba, Puerto Rico, Trinidad, and first seen in Hawaii in 1959. It is transmitted mechanically or by the green peach aphid, Myzus Persicae, and other aphids including the green citrus aphid, Aphis spiraecola, in Puerto Rico. Two forms of mosaic virus are reported in Puerto Rico: the long-known "southern coast papaya mosaic virus", the symptoms of which include extreme leaf deformation, and the relatively recent "Isabela mosaic virus" on the northern coast which is similar but without leaf distortion. Both forms occur in some northcoast plantations. There is no remedy, but measures to avoid spread include the destruction of affected plants, control of aphids by pesticides, and elimination of all members of the Cucurbitaceae from the vicinity. Mosaic is sporadic and scattered and not of great concern in Queensland.