Update 0.5.3 is live!
Epidemics are deadly diseases that spread among citizens. They originate from livestock farms and trading ports. After infecting one or more of its workers it will spread from their homes to neighboring houses.
An epidemic can be contained using purification bonfires. The bonfires can be placed in housing zones that are already getting health effect from a Doctors’ building. There can be as many bonfires as doctors were in the city at the beginning of the epidemic.
After the epidemic ends you will have access to the total number of casualties.
Epidemics and the use of bonfires in ancient Mesopotamia
The idea of adding bonfires to the game comes from reading the article Epidemics in the cradle of civilization by Troels Pank Arbøll:https://sciencenordic.com/denmark-epidemic-history/epidemics-in-the-cradle-of-civilization/1758958.
The author mentions cases of rituals during epidemics in ancient Mesopotamia to prevent further deaths, “which culminated in the burning of a brush pile. Whether or not this incineration was an act of purification, or a means to handle large amounts of casualties, remains unknown.”
So, we may not know all the details about these rituals but we do know that they use fire, and that large pyres would have been burned at times during epidemics in ancient Mesopotamia.
Anyway, if you just want to get rid of all epidemics in your cities there is no need to perform purification rituals to appease the gods. They can be can be switched off from the Settings screen.