How does William Shakespeare use imagery in Coriolanus?

In Act III, Scene I, the imagery of the state as a diseased body becomes dominant.
Coriolanus calls the people "measles" that "tetter us", speaks of the wars they
fear as touching "the navel of the state", and refers to the common people as a
"bosom" (stomach), so reversing the allegory of Menenius; they are a
"multitudinous tongue" licking up a poison that will kill the state. Meanwhile
Coriolanus himself appears to the tribunes as "a disease that must be cut away"
and as "a gangrened foot".