loupingill

Louping ill is an infectious disease affecting sheep and other ruminants, primarily in the United Kingdom. It is caused by the louping ill virus, a type of flavivirus. The virus is transmitted by the sheep tick, Ixodes ricinus, which is common in upland and moorland areas.

The disease is characterized by neurological signs, hence the name "louping ill," which is derived from the Scottish word for leaping or jumping. Infected animals may exhibit tremors, staggering gait, incoordination, and sometimes convulsions or paralysis. The mortality rate can be high, particularly in young or naive animals. Sheep are the most commonly affected species, but the virus can also infect cattle, red grouse, and, rarely, humans. In humans, infection can cause a febrile illness with neurological complications.

Louping ill is endemic in certain parts of the UK, with outbreaks often occurring in late spring and summer when tick populations are most active. Control measures focus on tick control through dipping or pour-on treatments for livestock. Vaccination is also available for sheep and cattle and is a key tool in preventing outbreaks in at-risk areas. Farmers in affected regions often implement vaccination programs as a routine part of flock and herd management. The virus can also circulate in wildlife populations, contributing to its persistence in the environment.