When one spends hours and hours of days adding the album art to their iPod or iPhone because they downloaded music and it didn't come with album artwork.
Then making sure that each album has the appropriate song in the right album.
Symptoms usually include countless hours of sleep loss, drinking dangerous amounts of energy drinks, punching people in the face who question your awesome skills of album arting, urges to smoke meth to stay awake to cure "the plague", then showing off your progress to everyone in sight and making them admire your work before you Falcon Punch them in their jealous face!!
AHHHHHHH!!!! The Album Art Plague has my iCOD feeling like a crack baby in rehab, atleast I only have 600 more songs to do, the 400 i have done only took me a week.