Harry är inte en Horcrux.
Som bekräftat av följande citat från JKR (som jag kopierade från detta svar från den enda @ Slytherincess):
"Here is the thing: for convenience, I had Dumbledore say to Harry, "You were the Horcrux he never meant to make," but I think, by definition, a Horcrux has to be made intentionally. So because Voldemort never went through the grotesque process that I imagine creates a Horcrux with Harry, it was just that he had destabilised his soul so much that it split when he was hit by the backfiring curse. And so this part of it flies off, and attaches to the only living thing in the room. A part of it flees in the very-close-to-death limbo state that Voldemort then goes on and exists in. I suppose it's very close to being a Horcrux, but Harry did not become an evil object. He didn't have curses upon him that the other Horcruxes had. He himself was not contaminated by carrying this bit of parasitic soul."
source
Han har bara en del av Voldemorts själ på en eller annan sätt "bifogad", parasitärt, till sin egen. Den kraftfulla Dark Magic som omger en sann Horcrux finns inte i honom: Voldemort gick aldrig igenom den processen med honom, eftersom denna själsuppdelning var oavsiktlig. Det är denna Dark Magic som skyddar Horcrux från skador av låga nivåer, så det finns ingen anledning att Harry borde vara så skyddad från sådana stavningar som de sanna Horcruxesna är. Det är vettigt att ett själfragment utan speciell magi inte har något särskilt skydd. En del av magiken som är inblandad i att skapa en sann Horcrux måste vara att skapa sådant skydd.
Från Muggles Guide till Harry Potter :
A soul fragment bound to an object, a Horcrux, is proof against ordinary magic, even magic as strong as that produced by an extraordinary wand. (At least, evidence is that Dumbledore believed so, and we have seen nothing against that.) The soul fragment within Harry is not actually bound to him, but is merely clinging to his own soul, and as such is only as strong as Harry himself; if Harry's soul is separated from his body, the soul fragment is detached and vanishes.