Bacterial Infection - Rotting, more specifically spoiling
Fungal Infection - Rotting, more specifically nature is trying to recycle you
Viral Infection - A cargo cult has appropriated your systems and has re-purposed you as a tool for their survival.
Cancer - Uncontrolled self cultivation
Fracture (traumatic) - Structural failure, mechanical
Fracture (stress) - Structural failure, engineering related
Seizures - Control system overload
Coma - Control systems failure
Cramps, spasms - Treason, sedition
Bacterial infections definitively feel like rotting.
Yeah they do.