I was testing out the interaction between Nix Informer and Venedon (which seems to work fine), and wondered if the same trick would work with the Defiler perk Lingering Sickness, since it uses the same verbiage.
Unfortunately, not only did it not work, but further testing also revealed that Lingering Sickness actually doesn’t affect any debuff. Venedon’s trait works as expected.
Short video of this:
I doubt that it matters, but for the record I’m playing on Windows.