Answer: Oh! Blue veins and curling leaves. That makes more sense! You have done a superb job describing the exact symptoms of Tomato Spotted Wilt Virus (TSWV). As a virus, a fungicide will have no effect so I'm sorry the greenhouse person gave you false hope. TSWV is transmitted from infected plants to healthy plants by at least nine species of thrips. Thrips are tiny (approximately 1/16th of an inch) winged insects that feed on plants through sucking mouthparts. Thrips transmit the virus in a persistent manner, which means that once the insect has picked up the virus, it is able to transmit the virus for the remainder of its life. The virus is not passed on from adult to egg; however, progeny that develop on infected plants will quickly pick up the virus and be effective disease vectors.
Controlling this disease is difficult. The wide host range, which includes many perennial ornamentals and weeds, enables the virus to successfully overseason from one crop to the next. And, as you've discovered, once your tomato plants contract the disease, it is fatal. So, your best option is to choose tomato varieties that have shown some resistance to TSWV. Amelia, BHN 601, BHN 640, Crista, Nico, Red Defender, Quincy, Talladega, and others are good choices for seeds. If you purchase plants, read the label identifying the cultivar and make sure it has TSWV resistant on the label. It doesn't matter whether you grow your plants in the ground or in containers or on your patio - thrips will find them so plant resistant varieties.
Glad we could follow up on your original questions!
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