European rabbits face two introduced viral diseases that cause mass mortality events, affecting both wild populations and the predators and ecosystems that depend on them.
Myxomatosis causes severe swelling of the eyes, nose, and genitals with progressive blindness and secondary infections before death over days to weeks. Affected rabbits suffer intensely. RHD causes acute hemorrhagic disease with rapid death in some cases, but also chronic suffering in resistant strains. Population crashes leave surviving predators facing food shortages with cascading ecosystem effects.