Answer: Based on your description I would more likely suspect that what you are seeing is a combination of a touch of frost damage combined with some spittle bugs than a virus. The foamy deposit sounds very much like the sort of frothy goop (resembling for all the world spit) produced by the spittlebug larvae -- hence the name. While they suck plant juices, they are not usually numerous enough to damage the plants severely. You can certainly remove the "spittle" by hand or with a strong burst from the hose. If the other damage is unsightly, remove the affected parts and expect normal growth to ensue. If you still suspect a virus, you might wish to take a sample to your County Extension (489-4315) for a more precise diagnosis and suggested remedies.
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