Okay maybe its even a bug. But i never saw it otherwise. Rats dont attack from themselve-
So the plague doesnt seem as a threat at all. If it is intended would it be great if there was a config option to make them aggressive.

Rats are already classed as hostile, but I can try and toy around with making them attack certain things anyways.

I have made them more aggressive by default in this current update. Please report any bugs here.