What is Rabies? 

Rabies is a fatal viral disease of mammals and occurs infrequently in horses. The Centers for Disease Control and Prevention report that equids account for less than 1% of all rabies cases in the USA; the total number of equine cases has historically ranged from 25–82 annually.

Clinical Signs: The clinical signs of rabies can be highly variable and can include lameness, colic, painful urination (can present as colic, stretching to urinate), and neurologic abnormalities. Insidious onset (slow to develop clinical signs) is extremely common. 

• In unvaccinated horses, rabies is rapidly progressive after onset of clinical signs with death occurring 5-7 days following the onset of clinical signs.
• Physical signs may include:
  • Fever 
  • Loss of appetite 
  • Blindness o Difficulty swallowing
  • Hypersensitivity of the skin- can sometimes present as self-mutilation 
  • Muscle twitching o Lameness 
  • Paresis and/or ataxia- loss of body control
  • Incontinence 
  • Paralysis – beginning in the extremities o Sudden death

Behavioral signs:

• Dumb form: depression/stupor 
• Furious form: mania – excitable, fearful, may exhibit aggression. These horses are extremely dangerous.

Diagnosis: There is no ante-mortem (prior to death) test for rabies. Diagnosis is made by testing brain samples during a necropsy which requires specific biosecurity measures. Veterinarian will attempt rule out other possible causes of disease such as EEE, WNV, EHM, EPM, and other diseases known to cause similar clinical signs.

Treatment: There is no cure for rabies. Rabies is fatal in all horses with clinical signs. 

Prevention: All horses should be vaccinated annually for rabies.