Also, there is...

 Geneology Pox
Author UNKNOWN

 WARNING:  Very Contagious to Adults!!

 Symptoms:  Continual complaint as to need for names, dates, and
 places.  Patient has blank expression, some times deaf to spouse
 and children and grandchildren.  Has no taste for work of any kind
 except feverishly looking through records at libraries and court houses.
 Has compulsion to write letters.  Swears at mailman when he doesn't
 leave mail.  Frequents strange places, such as cemeteries, ruins, and
 remote desolate country areas. Makes secret night calls.  Hides phone
 bill from spouse.  Mumbles to self.  Has strange faraway look in eyes.

 NO KNOWN CURE:  Medication is useless   Disease is not fatal but
 gets progressively worse.  Patient should attend genealogy work-shops,
 subscribe to genealogy magazines and be given a quiet corner in the
 house where they can be alone.

 REMARKS:  The usual nature of this disease is  "The Sicker the patient
 gets, the more they enjoy it".