However, one savvy fan has pointed out on Reddit that there could be solution on the horizon: Quaithe of the Shadow.
If you can't remember the name, you'll probably remember the face: Quaithe made a couple of appearances during Season 2 in a fetching balaclava made of gold coins, predicted the future and told Jorah that yes, she knew he loved Daenerys, and she knew where her dragons were.
What Jorah rebuffed at the time, however, was another useful tip, which can now be seen as a prediction after his fateful journey to Old Valeryia, home of greyscale, in Season 5:
In the books, Quaithe implies that she is capable of shadow magic, like Melisandre. It's unlikely that this could cure Jorah's greyscale, but she does seem to know how to prevent it.
Of course, this is assuming that Jorah will even appear in Season 7. Thankfully, the actor who plays him, Iain Glen, has been spotted on a plane to Belfast, where much of Game of Thrones is filmed, with fellow Thrones actress Gwendoline Christie in June.
While a fan on the plane spotted Glen reading a script, it probably wasn't for Season 7: at Comic-Con at the weekend the cast said they hadn't received those yet.
Instead, Christie and Glen may have been going over for either a costume fitting or some stunt choreography. Either way, he shall appear after the seventh season starts next summer. As for how scaley Jorah will be, however, we'll just have to wait and see.