Equine Viral Arteritis

Equine Viral Arteritis

1. Infects donkeys, horses and other equids

   • Not humans
   • It is notifiable in
     • Stallions
     • mares that have been inseminated or mated in last 14 days

2. Signs include

   • Conjuctivitis
   • Swelling of testicles and udder
   • depression
   • anorexia
   • leukopenia
   • nasal discharge
   • fever

3. The virus

   • Small
   • enveloped
   • single stranded RNA
   • genus Arterivirus, family Arteriviridae, order Nidovirales
   • outside the body dies quickly
   • in tissue or body can survive freezing for prolonged periods of time
   • common around world except Japan and Icealand

4. pathogenesis

   • Respiratory exposure
     • invades upper and lower respiratory tract
       • replicate in lymph nodes and enter bloodstream
         • day 6-8 enter vascular endothelium
           • causes
             • neutrophilic infiltration
             • enodthelial degredation and swelling
             • necrosis of tunica media
           • also enters the semniferous tubules
           • thyroid
           • liver
           • maximal injury day 10
   • mares easily infected by venereal route
     • leading to abortion from myometrius