In researching genealogy, you may find ancestors who were considered idiotic or blind. In many cases these symptoms were the result of some childhood illness such as Measles.
German measles is a mild viral illness caused by the rubella virus.
Rubella, also called German Measles or three-day Measles, and highly contagious disease caused by the rubella virus. It begins with a rash on the face and spread all over the body. Most children are immunized beginning at 12 months of age. Years ago, before effective prevention, Measles, Mumps, and Rubella were common, serious childhood diseases. A virus that wasn t identified until 1962 caused rubella, the disease itself was first described late in the 18th century.