I destroy everything with a suspected virus. I didn't build a collection for 17 years to have them destroyed by a virus.
Mary it's not easy to tell the difference. The Virus splash is always a darker color than the petal (see Mark's post) and is uneven in appearance. It can sometimes distort the petal. If a 'color break' as it is usually referred to is white we call them chimeras and the cause is unknown, but considered to be harmless.
For a long time people would pay crazy prices for virus infected plants but eventually most of them have realized that it's not pretty. You can see many of them being sold on Ebay. Even if you wanted one, you would have no guarantee that it would repeat. From way back when, 'Princess Victoria' was always thought to have the color break. I've had a tree of this variety for many years and it has never displayed the phenomenon.
If a 'pattern' on a petal is even and repeats, it is not a virus induced one but part of the color of the flower. For instance in this variety (Madame Poni):
