European brown hare syndrome (EBHS), also called viral hepatitis of hares, is a disease of the hare species Lepus europaeus and Lepus timidus.
The disease was first described in Scandinavia in the 1980s and has since occurred in numerous European countries; several cases have been reported in Germany as well. The causative agent of EBHS is a calicivirus (genus Lagovirus), which only causes the disease in hares. As far as is known, rabbits (and other animal species, too) are not affected. The virus is shed in all secretions and excretions and is very environmentally stable. Transmission presumably occurs directly, particularly faecal-orally or indirectly through contaminated water and feed. The disease is peracute to acute and is characterised by a very high morbidity and mortality rate (up to 100%). If at all possible, signs are rarely observed in free-living wildlife. They include: weakness, apathy, disorientation, loss of shyness and movement disorders (e. g. paralysis of the hind legs). There is no known therapy.