CPD Article | EQUINE
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decrease insect populations.
○ ○ Removal of stagnant water (breeding ground
for midges).
○ ○ Use of fly sheets and hoods for horses.
Disinfection of aircraft, stables or other materials
used in transporting animals to prevent
transportation of insect vectors or infected blood.
Strict quarantine for horses imported from Africa.
Slaughter of infected horses.
Horses with a fever and suspected AHS should be
kept in insect-free stables to prevent potential virus
transmission to the vector.
Movement control.
Expected response to treatment
• Poor response in pulmonary, mixed and some
cardiac forms.
• Resolution of fever, palpebral edema and other
clinical signs in some cardiac and all horse sickness
fever cases.
Reasons for treatment failure
• No vaccine provides full protection, therefore
vaccinated horses can still be clinically and
subclinically infected with AHS.
Further Reading
Prophylaxis
• Vaccination with polyvalent or monovalent
attenuated vaccines, however no vaccination
provides 100% protection due to the presence
of different AHSV strains and in some countries,
vaccination is not allowed.
• Used either in face of outbreak in epizootic areas or
2 months before insect season begins in enzootic
areas.
• Foals acquire passive immunity from vaccinated
mares via ingestion of colostrum. Antibody levels
decline to negligible values by 4-6 months old.
• Vaccination against AHS not currently allowed in
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Outcomes •
Prognosis
• Pulmonary form: invariably fatal.
• Cardiac form: 50% or greater mortality.
• Mixed form: 70-80% mortality.
• Horse Sickness Fever: mortality rare.
• Mortality of up to 95% in susceptible populations.
• Death is rare in donkeys and zebra.
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Recent references from PubMed and VetMedResource.
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Transboundary and emerging diseases. 64(5), 1579-1588
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Diouf N D, Etter E, Lo M M, Lo M & Akakpo A J (2013) Out-
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Aradaib I E (2009) Pcr detection of African Horse Sick-
ness Virus serogroup based on genome segment three
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Fernández J, Fernández-Pacheco P, Rodríguez B, Sotelo
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Agüero M, Gómez-Tejedor C, Angeles Cubillo M, Rubio
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Herholz C, Fussel A E, Timoney P, Schwermer H, Bruckner L
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