Pokémon X and Y Playthrough Discussion

Just bred an Electrike with 31 IVs in SpA/Speed, and a Modest nature. I began trying to pass Pokerus on to him from a Skrelp, but had to afk for a few hours, and the Skrelp's Pokerus disappeared and the Electrike was already immune. Does this crap only last a few hours now compared to days (I think) in the past?

Apparently it disappears once your clock hits midnight. or at least it did, I can confirm that a few of my pokemon with Pokerus were cured when they were left in my party and it hit midnight.