I wanted to see how far I can push the game while staying T1 Town Center.
Is there any way to get rid of rats without the Rat Catcher? At some point the plague starts killing like 15-25% of your population.
The only way to deal with it I’ve found is to literally move all of your houses somewhere else (the rats just stay on the old ground…). Obviously - not a good long term solution 
EDIT: Changed the title because it wasn’t really obvious on a first glance that it’s a question.
How many in-game years have passed?
I mean I’m at Y30, the rats started spawning at like Y15.
The best I could get to was 210 population.
Anyone has any idea what’s the … radius of a rat? Like from what I could see if a house gets infected it will spread to the other houses, but there seemed to be some sort of a radius of infection.
I want to retry my T1 run and I guess if I build the houses spread enough I can just remove the infected ones.
My current hypothesis is that the number/frequency of the rats that you get is tied directly to how much grain you produce, meaning more grains = more rats.
I didn’t have any rats (or at least I didn’t get the little bubble pop up on my screen) until I made it to T3, built the brewery, and started growing wheat. After that point I was getting rats popping up out of nowhere and had to quickly build some rat catchers to deal with the problem.
I haven’t tried this yet but I bet if you got your wheat number to 0 the rat problem would go away.
Got 0 grains - no use for them at T1.
It’s fish, beans/peas and meat.
I think it’s probably more tied to the years than that.