IPA: /əˈflɪktɪvli/
KK: /əˈflɪktɪvli/
In a way that causes pain, suffering, or distress.
The disease spread afflictively, causing widespread suffering.
Afflictively is formed from "afflict" (from Latin "afflictus", meaning to strike down or trouble) and "-ively" (a suffix forming adverbs meaning in a manner of). The word describes an action done in a manner that causes distress or suffering.
Think of the word 'afflict' meaning to cause trouble or distress, and remember that 'afflictively' means doing something in a way that brings about that distress.