Recently got a sickness infliction from a pool, it seems to last a VERY long time. Still waiting for it to abate but it outlasted 2 blessed stomfillia and probably a lot longer than that too.
Might be related. I ate kobold corpse while starving and got sick for several in-games dates. Fever wasn't striking after initial attempts to fight ot off with first aid.
So I stuck with lowered stats for a while until dead. Not sure for how long.