RHDV2: What Rabbit Owners Need to Know
Rabbit Hemorrhagic Disease (RHDV)is a highly contagious and fatal calicivirus. This deadly virus affects both pet and wild rabbits. RHDV kills quickly, giving little warning. A safe and effective RHDV2 vaccine is available. We strongly recommend that all rabbit caregivers (including fosterers and shelters) vaccinate their companion bunnies ASAP.
Any sudden death, especially in an otherwise healthy rabbit, is suspicious and should be reported to your veterinarian as a possible case of RHD.
RHDV2 regulations by US state from Wabbitwiki.com