Protecting Pets from West Nile Virus

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Can West Nile Virus cause illness in dogs or cats?

West Nile Virus (WNV) can infect pets but they rarely exhibit noticeable symptoms. The Center for Disease Control has isolated the virus from both dogs and cats. Most dogs and cats infected with the virus fully recover. There is no specific treatment.

How do dogs and cats become infected with WNV?

Dogs and cats become infected the same way humans become infected, by the bite of an infected mosquito.

Can infected dogs or cats be carriers and transmitters of WNV to humans?

There is no documented evidence of person-to-person, animal-to-animal or animal-to-person transmission of the virus. Preliminary studies do not indicate that the virus is transmitted in the saliva of infected pets. Therefore, if bitten by an infected pet there is little risk for the spread of WNV. However, other diseases may be spread through your pet’s saliva. Veterinarians should take normal infection control precautions when caring for an animal suspected to have this or any other viral infection.

What are the symptoms in cats and dogs?

It is unlikely that WNV symptoms will be noticeable in your pet. However, there are certain clinical signs that may indicate disease, such as coordination loss, depression, decreased appetite, difficulty walking, tremors, abnormal head posture, circling, and convulsions. It is important to remember that these signs may indicate other very serious neurological conditions and may not necessarily mean that your pet has WNV.

Should a dog or cat infected with West Nile Virus be put down? What is the treatment for an animal infected with West Nile Virus?

There is normally no reason to put down an animal that is infected with WNV. Full recovery from the infection is likely. Treatment would be supportive and consistent with standard veterinary practices for animals infected with any virus. Be sure to consult your veterinarian to ensure an accurate diagnosis. Confirmation of a WNV diagnosis is usually accomplished with a blood test.

How can I protect my pet?

There is currently no vaccine available for household pets. Pet owners should not apply human products to pets. Pets may suffer serious side effects by ingesting human-labelled products. Consult your veterinarian for additional information on pet protection. If you are concerned about high mosquito populations in your area, use products specifically designed for safe use on companion animals and reduce mosquito breeding grounds around your home. Mosquitoes are most active between dusk and dawn so keep pets indoors during these periods.

Source: Centers for Disease Control