WEST NILE VIRUS IN DOGS
Knox County Health Department 9/23/2002
There is no documented evidence of animal-to-person transmission of WN virus. Because WN virus is transmitted by infectious mosquitoes, dogs or cats could be exposed to the virus in the same way humans become infected. Veterinarians should take normal infection control precautions when caring for an animal suspected to have this or any viral infection. It is possible that dogs and cats could become infected by eating dead infected animals such as birds, but this is undocumented.
There is no reason to destroy an animal just because it has been infected with WN virus. Full recovery from the infection is likely. Treatment would be supportive and consistent with standard veterinary practices for animals infected with a viral agent.
The dog recently reported to be infected with WNV was immunocompromised and remains the only one in 3 years of WNV in the country where the virus was thought to cause an encephalitis. (All previous reports of such have been found to be lab errors after further study.) In three years of experience, there has not been an increase of encephalitis problems in dogs in areas with heavy and prolonged exposures to WNV circulation. If it occurred to any significant degree, we would have seen many cases by now.
CDC and Illinois consider this to be a sporadic occurrence in a young or immunocompromised individual and not a change in the virus pathology. If enough "samples" are examined of any species, you most certainly would find a few sporadic clinical cases infected with a virus known to produce meningoencephalitis in selected species.
UT College of Veterinary Medicine