Rabbit haemorrhagic disease virus (RHDV) is a calicivirus of the genus Lagovirus that causes rabbit haemorrhagic disease (RHD) in adult European rabbits (Oryctolagus cuniculus). RHD primarily spreads between rabbits through ingestion and inhalation of the virus. The virus is present in the urine and feces of infected rabbits, making contaminated bedding, food, or forage potential sources of infection.