Louping-ill () is an acute viral disease primarily of

sheep Sheep or domestic sheep (''Ovis aries'') are domesticated, ruminant mammals typically kept as livestock. Although the term ''sheep'' can apply to other species in the genus ''Ovis'', in everyday usage it almost always refers to domesticated s ...

that is characterized by a biphasic

fever Fever, also referred to as pyrexia, is defined as having a body temperature, temperature above the human body temperature, normal range due to an increase in the body's temperature Human body temperature#Fever, set point. There is not a single ...

, depression,

ataxia Ataxia is a neurological sign consisting of lack of voluntary coordination of muscle movements that can include gait abnormality, speech changes, and abnormalities in eye movements. Ataxia is a clinical manifestation indicating dysfunction of ...

muscular Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much longer than in the other types of muscle ...

incoordination,

tremor A tremor is an involuntary, somewhat rhythmic, muscle contraction and relaxation involving oscillations or twitching movements of one or more body parts. It is the most common of all involuntary movements and can affect the hands, arms, eyes, fa ...

s, posterior

paralysis Paralysis (also known as plegia) is a loss of motor function in one or more muscles. Paralysis can also be accompanied by a loss of feeling (sensory loss) in the affected area if there is sensory damage. In the United States, roughly 1 in 50 ...

coma A coma is a deep state of prolonged unconsciousness in which a person cannot be awakened, fails to respond normally to painful stimuli, light, or sound, lacks a normal wake-sleep cycle and does not initiate voluntary actions. Coma patients exhi ...

, and death. Louping-ill is a

tick Ticks (order Ixodida) are parasitic arachnids that are part of the mite superorder Parasitiformes. Adult ticks are approximately 3 to 5 mm in length depending on age, sex, species, and "fullness". Ticks are external parasites, living by ...

-transmitted disease whose occurrence is closely related to the distribution of the primary vector, the sheep tick ''

Ixodes ricinus ''Ixodes ricinus'', the castor bean tick, is a chiefly European species of hard-bodied tick. It may reach a length of when engorged with a blood meal, and can transmit both bacterial and viral pathogens such as the causative agents of Lyme disea ...

''. It also causes disease in

red grouse The red grouse (''Lagopus lagopus scotica'') is a medium-sized bird of the grouse family which is found in heather moorland in Great Britain and Ireland. It is usually classified as a subspecies of the willow ptarmigan but is sometimes consider ...

, and can affect humans. The name 'louping-ill' is derived from an old Scottish word describing the effect of the disease in sheep whereby they 'loup' or spring into the air.

Cause

Louping ill is caused by

RNA Ribonucleic acid (RNA) is a polymeric molecule essential in various biological roles in coding, decoding, regulation and expression of genes. RNA and deoxyribonucleic acid ( DNA) are nucleic acids. Along with lipids, proteins, and carbohydra ...

virus called Louping ill virus. Louping ill virus belongs to genus ''

Flavivirus ''Flavivirus'' is a genus of positive-strand RNA viruses in the family ''Flaviviridae''. The genus includes the West Nile virus, dengue virus, tick-borne encephalitis virus, yellow fever virus, Zika virus and several other viruses which may caus ...

'', family Flaviviridae. There are four subtypes: British, Irish, Spanish and Turkish.

Prevention

According to a ProMED article, disease in sheep has been controlled in the UK by a vaccine (

ATCvet The Anatomical Therapeutic Chemical (ATC) Classification System is a drug classification system that classifies the active ingredients of drugs according to the organ or system on which they act and their therapeutic, pharmacological and chemical p ...

code: QI04AA01), originally developed by Scotland's

Moredun Research Institute The Moredun Research Institute is a scientific research institution based at the Pentlands Science Park, in the Bush Estate area of Midlothian, Scotland. It conducts research into diseases of farm livestock and the promotion of animal health and ...

by Prof

John Russell Greig John McDougal Russell Greig CBE FRSE MRCVS (September 1889-1 May 1963) was a Scottish veterinarian who was Director of the Moredun Research Institute from 1930 to 1954. He is noted for the development of several important animal vaccines: Enzoo ...

. In 2009, however, a shortage of vaccine combined with an increase in the number of ticks found in sheep pasture areas cause an increased risk of this disease.

References

* *

External links

Moredun Research Institute vaccine article
* WHO vaccine listing: ) {{Zoonotic viral diseases Sheep and goat diseases Animal viral diseases Viral encephalitis Flaviviridae