to let you see the final stage of the infection in the icewings bodies I will drop a image I found the unique icewings stages are and there will be multiple entrances depending on which character you want to start with

Stage one infection: The subject has had a injury caused by an infected: the area will swell and wont bleed much but the icewings blood goes from blue to black

Stage two: subject becomes restless, the affected area grows worse with visible rotting, they have a intense urge to stay away from groups of dragons and become aggressive when approached

Stage three: the area around the affected area has rotted and is leaking Black blood constantly, flesh inside the mouth of the infected dragon becomes as black as a Black mamba's, they start to grow more teeth from the inside of the throat, gums, and tongue, and they loose the ability to string together thoughts when speaking

Stage four: At this stage, a white bile coats the teeth of the infected dragon, claws and teeth grow larger as they grow emaciated and, the area around the affected area has completely rotted exposing bones and depending on the location, organs. the infected individual dragon will be hostile to all dragons, the dragon's mind is tricked into believing any dragon who approaches it means it harm

(the image does act like a hint to where it comes from)