1,454
edits
Changes
Jump to navigation
Jump to search
no edit summary
Also Known As: ''''' BEF — Dengue Fever — Lazy Man’s Disease — Stiff Sickness — 3 day Sickness — Dragon Boat Disease — Vil — Bovine Epizootic Fever — Stiffsiekte (South Africa)'''''
Also Known As: ''''' BEF — Lazy Man’s Disease — Stiff Sickness — 3 day Sickness — Dragon Boat Disease — Vil — Bovine Epizootic Fever — Stiffsiekte (South Africa)'''''
Caused By: '''''Bovine Ephemeral Fever Virus — BEFV'''''
Caused By: '''''Bovine Ephemeral Fever Virus — BEFV'''''
==Introduction==
==Introduction==
Bovine Ephemeral Fever is a '''[[Viruses|viral]] disease''' causing fever, dehydration, [[:Category:Alimentary Diseases - Cattle|gastrointestinal]], [[:Category:Reproductive Diseases - Cattle|reproductive]] and [[:Category:Neurological Diseases - Cattle|neurological]] disease in '''cattle'''. The pathogen involved is a [[Rhabdoviridae|rhabdovirus]].
Bovine Ephemeral Fever is caused by an RNA virus – a [[Rhabdoviridae|rhabdovirus]]. Typically there is a sudden onset of fever with a sudden milk drop. It is transmitted rapidly with evident lameness, depression and often anorexia. Recovery is often rapid – 3 day fever. Morbidity can be up to 100% but mortality is low (1-2%).
Due to its geographical distribution and association with heavy precipitation, BEF often occurs simultaneously with '''epizootics of [[Rift Valley Fever]].'''
Due to its geographical distribution and association with heavy precipitation, BEF can occur simultaneously with '''epizootics of [[Rift Valley Fever]].'''
BEF is not zoonotic.
BEF is not zoonotic.
Lymphadenopathy may be a feature as well as '''stiffness and lameness''' in the limbs with tremors/spasms and possible recumbency.
Lymphadenopathy may be a feature as well as '''stiffness and lameness''' in the limbs with tremors/spasms and possible recumbency.
Gastrointestinal disease may present as '''hypomotility''' and constipation or [[Diarrhoea|diarrhoea]]. Pregnant cattle may '''abort and infertility''' can occur in either sex. Cows may develop agalactia.
Gastrointestinal disease may present as '''hypomotility''' and constipation but occasionally there can be [[Diarrhoea|diarrhoea]]. Pregnant cattle may '''abort''' whilst '''infertility''' can occur in either sex. Cows may develop agalactia.
Other signs may include dullness, depression, lethargy and coma in severe cases. Some animals develop '''respiratory''' disease and '''subcutaneous emphysema, oedema and crepitation'''.
Other signs may include dullness, depression, lethargy and coma in severe cases. Some animals develop '''respiratory''' disease and '''subcutaneous emphysema, oedema and crepitation'''.
Hot weather increases mortality in epidemics.
Hot, moist weather increases mortality in epidemics.
'''''Severe''''' – lateral recumbency, paralysis, reflex loss, subcutaneous emphysema, tachycardia and tachypnoea, mortalities. Residual paralysis may remain after resolution of fever.
'''''Severe''''' – lateral recumbency, paralysis, reflex loss, subcutaneous emphysema, tachycardia and tachypnoea, mortalities. Residual paralysis may remain after resolution of fever.
Viraemia usually lasts '''3-5 days''' after which recovery and natural immunity are life-long.
Viraemia usually lasts '''3-5 days''' after which recovery is rapid and natural immunity is long lasting.
==Diagnosis==
==Diagnosis==
Diagnosis is often based on '''clinical observations''' of various stages of disease present simultaneously and '''history''' of sudden onset outbreaks on the farm or neighbouring units.
Diagnosis is often based on '''clinical observations''' of various stages of disease present simultaneously and '''history''' of sudden onset outbreaks on the farm or neighbouring units.
'''Isolation of virus from blood''' taken during '''pyrexic phase''' is most efficient laboratory method of diagnosis. The virus can be identified by '''[[immunofluorescence]] or immunostaining.'''
'''Isolation of virus from blood''' taken during '''pyrexic phase''' is the gold standard laboratory method of diagnosis, but is demanding. Molecular diagnosis is preferred these days. The virus can also be identified by '''[[immunofluorescence]] or immunostaining.'''
A '''rising antibody titre''' when sampled during fever and 2 weeks later is also confirmatory.
A '''rising antibody titre''' when sampled during fever and 2 weeks later is also confirmatory.
On post-mortem, only generalised inflammatory changes are evident with neutrophilic infiltration of tissues and muscle necrosis. Straw coloured fibrinous fluid is often present in several cavities.
On post-mortem, generalised inflammatory changes are evident with neutrophilic infiltration of tissues and muscle necrosis. Straw coloured fibrinous fluid is often present in several cavities.
==Treatment==
==Treatment==
==Control==
==Control==
'''Vaccines''' are available in Japan, Australia and South Africa. Annual boosters are essential to maintain immunity. All are too '''expensive''' for use in developing countries.
'''Vaccines''' are available in Japan, Australia and South Africa. Annual boosters are essential to maintain immunity. All are '''expensive''' for use in developing countries.
Vector control is theoretical and almost impossible. Quarantine also has no impact upon local spread due to vector transmission. '''Movement regulations''' vary with country and time and should be adhered to.
Vector control is theoretical and almost impossible. Quarantine also has no impact upon local spread due to vector transmission. '''Movement regulations''' vary with country and time and should be adhered to.
Cattle in good health usually recover quickly and have a long lasting immunity.
[[Category:Rhabdoviridae]][[Category:Cattle Viruses]]
[[Category:Rhabdoviridae]][[Category:Cattle Viruses]]
[[Category:CABI Expert Review]]
[[Category:CABI Expert Review]]
[[Category:Expert Review Completed]]