@Ichijoe  
Wow. That is… the biggest reach I’ve ever heard in my life.

Vaccines and medicine aren’t transmitted either, so I don’t see your point.

So what would you call… Say a Flu Vaccine then? Surely to some People this too could be some type of Potion. That or indeed any other kind of medicine.

The cutie pox were the result of a potion, though, not an illness. It’s be extremely strange if potion effects could be transmitted like that.

Because Applebloom has, had the Cutipox, and as with such childhood diseases. i.e. The Scoota-pox. She probably passed it on to Sweetie Belle, and Scootaloo. Well, that would be the way I’d explain it, if it were my job to do so. Given that the condition seems to have been both rare, and largely unknown by the mass populous of Ponyville. Generally causing much panic, and mayhem. I’m of my own headcanon that they’re all likely carriers now, and still possibly young enough to still be unstable. Unlike those without the affection. So I almost see it almost like an overly active, ticked off immune system.

@Ichijoe  
But then… why wouldn’t the cutie mark return to Apple Bloom like with the village ponies in the Cutie Map?

This is what I think may happen? Assuming the Cutiemarks as is aren’t the final ones on the Toys yet. But then this Fandom would be in more butthurt over their new Cutiemarks as well.

She’s growing a second Cutie Mark in the first panel! She just has Cutie Pox again!

…but it’s somewhat equal to scootaloo’s and sweetie belle’s…