Disease is easier to spread in society.

a hunter-gatherer
an agrarian
a nomad
a rural

Disease is easier to spread in a rural society. The people of a rural settlement are depending each other regarding marriage for example. In time, will occur a degeneration that will have as a result an weak imun sistem. 

I say no for the nomad peple because their food, for example, is various, they can married with different persons with are not part of theyr tribe or grup. 

An agrarian society due to his work in agriculture, therefore fresh air, physical effort, can be healthyer than a rural society. 

On the other hand, a hunter- gatherer society is a primitive society and can be exposed to a disease by eating infested meal but this is not quite a danger.

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