This is common. Macoboy (1998) says

"Happily, virus diseases are not a worry. The only one of which I am aware is indeed often welcomed: it is responsible for creating the variegated versions of many red and pink camellias....The virus occasionally shows up in the leaves as yellow mottling, but it rarely affects more than a twig or two. The vigor of the plant won't be noticeably reduced unless practically every leaf comes mottled."

Yes, and you might watch for any blooms on that limb to see if they produce a sport that is different from the others, you may have something interesting happen.

Thanks, that is good info. It is similar to the leaves on a Golden Pothos (Scindapsus aureus), and is here and there over the entire plant.