The reason behind closing of Ghettos was Typhus and typhoid fever (disease). Ghetto can be defined as a part of a city where minority people or groups used to live due to the result of social and economical pressure. The ghetto is often described as a part or specific society which is more financially weaker than other areas of the city.
Versions of the ghetto appear worldwide, each with its own name, classification, and group of people. The term ghettos was originally used for the Venetian Ghetto in Venice, Italy in 1516, to define the specific part of the city where Jews were not allowed to enter and live, thus they differentiate from other people and created their own place.
The Prohibition Party is an example of a party that was created for a single purpose or goal. This party was created in the year 1869. The sole purpose of the Prohibition Party was to stop the manufacturing and sale of alcoholic beverages in the United States of America. I hope the answer helps you.