Tobacco Mosaic Virus On Tomato

It may be that your tomato plant has Tobacco Mosaic Virus (TMV). The "mosaic" appearance of the yellow/green tissues of the leaf, and what appears to be a "shoe-string" look (to a few of the leaves, but its really not very clear) is a characteristic symptom of this virus disease. Unfortunately viruses cannot be reversed or cured, however infected plants may produce edible fruit, but yield, size, and quality are reduced. We've included this link for your review. TMV is very easily transmitted when an infected leaf rubs against a leaf of a healthy plant, by contaminated tools, and occasionally by workers whose hands become contaminated with TMV after smoking cigarettes. We've included a web link with more info.
http://www.ipm.ucdavis.edu/PMG/GARDEN/VEGES/DISEASES/tobaccomosvir.html

It appears that your tomato plant has Virus. There are 3 virus possibility. WE have included links below. Two of the viruses are spread by aphids (sounds like the insect that you described). A third, the Tobacco Mosaic Virus, is very easily transmitted when an infected leaf rubs against a leaf of a healthy plant, by contaminated tools, and occasionally by workers whose hands become contaminated with TMV after smoking cigarettes. The "mosaic" appearance of the yellow/green tissues of the leaf, and what appears to be a "shoe-string" or ferny look is a characteristic symptom of a virus disease. Unfortunately viruses cannot be reversed or cured, however infected plants may produce edible fruit, but yield, size, and quality are reduced. Here are a few links that you might find helpful:
http://www.ipm.ucdavis.edu/PMG/r783102811.html
http://www.ipm.ucdavis.edu/PMG/r783102611.html
http://www.ipm.ucdavis.edu/PMG/r783102711.html