Respiratory disease presents as fever, nasal discharge, cough, lethargy and anorexia. Abortions associated with EHV type I infection tend to occur in the trimester and tend to epidemic in a herd. The aborted fetus is , not autolyzed, and is seen to have extensive liver damage upon necroscopy. Signs of myeloencephalopathy tend to begin after a six to ten-day incubation, then progress rapidly. Neurological signs include ataxia, muscle weakness, decreased tone of the tail, anus and vulva, paresis of the bladder, inability to urinate or retract the penis, orchitis, limb edema, deficits in cranial nerve five and other cranial nerves, vestibular signs, UMN signs and CNS signs. Diagnosis can be made through clinical signs and symptoms, case history of epidemic disease, nasal swab, serology and CSF analysis. . Expectorants (Sputolysine) and bronchodilators (Ventipulmin) help reduce the nasal discharge and cough associated with rhinopneumonitis and help to reduce aerosol transmission of the disease. Treatment for the respiratory form is The treatment for myeloencephalopathy is supportive including antiviral medications, NSAID’s, DMSO, CS, IV fluids, slings, catheters and feeding tubes. Prognosis for EHV type I infection is dependent on the type of disease. The respiratory form has a good prognosis for recovery while the prognosis for the neurological form is poor. Though there is recovery from the physical manifestations of disease there is the likelihood that the animal will have a relapse to the acute form of disease during times of high stress. Prevention of EHV infection is possible through vaccination for rhinopneumonitis. It has been demonstrated that individuals vaccinated against rhinopneumonitis are less likely to develop neurological disease associated with EHV type I, or to have less severe neurologic dysfunction if they are infected with a mutated strain of EHV type I.
Rabies
Rabies is caused by the zoonotic, neurotropic virus lyssavirus of the Rhabdovirus family.
The virus is transmitted from individual to individual through contact between the of an infected animal and the blood of another individual. Generally, this occurs when an infected animal bites another animal. Skunks, racoons, foxes and bats are the reservoirs. Once the virus is in the blood stream it travels to the nearest nerve. The virus enters the neuron and travels towards the within the cytoplasm of the nerve axon at a rate of three to four millimetres per hour. Once inside the spinal cord the virus enters the neurons of the spine to travel to the brain where it replicates rapidly causing damage and signs of cerebral lesions. Once infection has been established in the cerebrum some of the virus leaves the CNS to travel
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