In episode S5E09 of Game of Thrones we saw Jorah give a hand to help Dany from the Sons of the Harpy, given the fact that Greyscale infection spreads by touch, does this mean Dany is infected?
A quick google image search shows that Jorah's grayscale is on his left forearm:
He takes Dany's hand with his right hand, while both his forearms are covered by leather bracers:
I guess it's possible that whatever drives the disease could exist elsewhere on the skin without being visible, or might be like systemic viruses that cause rashes to develop in random places - but I don't see any reason to believe that.
Neither Jorah nor Shireen developed theirs anywhere but where the source touched, and it spreads slowly from where it starts rather than appearing in blotches - suggesting it needs direct contact to spread.
So Dany's safe - unless Jorah scratched and forgot to wash his hands...