Canine Distemper Virus - Seeker's Thoughts

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Seeker's Thoughts

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Canine Distemper Virus

Canine Distemper Virus


Canine Distemper Virus is an extremely contagious and fatal disease, once known to be one of the primary killers of shelter dogs prior to widespread vaccination programs. 


The virus spreads either directly through contact, airborne droplets of infectious secretions shed during respiratory infection and shedding, sub-clinically infected animals or through fomites (such as hands or equipment) or environmental surfaces (kennel bedding or dishes). Furthermore, this virus thrives for hours in damp environments and thrives well on nonporous materials like glass or plastic.


CDV can spread among dogs, other carnivores and certain mammals (including humans), most likely through aerosolizing viral body secretions from infected pets. Although highly contagious at all stages, incubation period between exposure to initial symptoms typically ranges from two-three weeks.


Infection with the virus leads to lymphopenia, fever and loss of appetite; symptoms are most pronounced among puppies and younger adult dogs. Replicated tonsils and lymph nodes spread the infection to epithelial tissues of lungs and gastrointestinal tract; after which it affects central nervous system (CNS) where symptoms such as myoclonus, encephalomyelitis, encephaloedema or chorioretinitis develop gradually despite supportive care measures taken against it.


If a dog does not possess adequate cell-mediated immunity, the virus will persist in epithelial cells of their respiratory and gastrointestinal tracts, potentially leading to lesions similar to kennel cough. Should it spread further into their CNS, symptoms could include lethargy, ataxia, vomiting diarrhea and seizures - potentially life threatening conditions for any pet.


Dogs suffering from neurological distemper tend to die. Histopathologic lesions found in infected canines' CNS include demyelination, gliosis and necrosis of neurons as well as demyelination of neurons, ependymal cells, choroid plexus cells, microglia and astrocytes - lesions which often prove fatal for infected dogs.


Europe and Russia have recently come across a mutant strain of canine distemper virus with more than double mortality compared to that seen with vaccine-derived strains. The new virus shares many of its genetic traits with original canine distemper virus, with only a single mutation (H5N1) responsible for increasing severity of disease symptoms.


If a dog displays symptoms of Canine Distemper Virus, his veterinarian will conduct tests to confirm this diagnosis and ensure it's not contagious. These may include taking throat, nose or eye swabs; blood, urine or bone marrow samples; as well as biopsies from footpads in order to test for presence of virus.