GENEALOGY WARNING!! Very contagious to mature adults. NO KNOWN CURE
SYMPTOMS: Mumbles to self. Makes secret calls at night. Hides phone bill from spouse. Has strange far away look in eyes. Has strong compulsions to write letters. Always includes a check in these letters. Swears at mailman when he leaves no mail. Continual complaints for names, dates, and places. Patient has blank expression, sometimes deaf to spouse and children. Has no taste for work of any kind, except feverishly looking through records at libraries and courthouses. Has compulsions to frequently visit strange places, such as cemeteries, ruins, and remote desolate country areas.
TREATMENT:
Medication is useless. Disease is not fatal, but gets progressively worse. Patient should be given a quiet corner of the house where he or she can be left alone. Patient should subscribe to as many societies, newsgroups, surname lists, and genealogical magazines as possible.
REMARKS: The unusual nature of this disease is... The sicker one gets, the more he or she enjoys it.

Author unknown
http://freepages.genealogy.rootsweb.ancestry.com/~parrottreilly/poems.html