I think, when the target of the spell gets diseased, its max HP should decrease -- you know, because it's CON gets reduced.

But I'm observing the opposite effect -- after disease sets in, the target gains HP and its max AP stays intact.

Anyone else having this problem?

As posted by someone on fextralife on Infect's page:

"This Skill appears to be bugged. If you Infect an enemy who has previously had damage dealt directly to his Vitality/Health bar, he will actually REGAIN HP up to the new maximum amount of Vitality that is determined by his reduced Constitution level set by the Diseased Status."

EDIT: wow. Just wow.

This happened to me just yesterday and I couldn't figure out why until I read this!