With West Nile virus spreading across the U.S., many pet owners have shared concern about their pet’s risk of infection. Most West Nile virus infections have been identified in wild birds and horses. Although the virus can infect dogs and cats, the risk of illness is very low.
West Nile virus is an arthropod-borne virus that causes encephalitis (swelling of the brain). The virus is transmitted by blood-feeding insects such as mosquitoes.
West Nile virus is a rare disease that spreads through mosquitoes that have fed on infected birds. Mosquitoes become infected after feeding on birds that are carrying the virus. Infected mosquitoes may then transmit the virus to humans and other animals. The virus cannot be transmitted directly between animals or from animals to people.
The risk West Nile virus poses to pets is very small. Elderly and young dogs, and those with compromised immune systems could be at higher risk. Pets have been exposed, but they have not fallen ill in great numbers. Cases of infection causing disease in pets are very rare and likely only in immunocompromised animals.
Cats may become ill with the virus, but dogs seem to be relatively resistant to developing clinical illness as a result of exposure to West Nile.
Symptoms of the virus in infected dogs are similar to signs exhibited by horses and include depression, decreased appetite, difficulty walking, tremors, abnormal head posture, circling and convulsions.
It is very important to contact your veterinarian if your pet shows any of these signs. There is currently no vaccine available for dogs and cats. The best way to prevent your pet from contracting the virus is to reduce the risk of mosquito bites.
Keep pets indoors during early morning and evening hours to reduce the risk of mosquito bites and possible exposure.
Prevent your pet from coming into contact with dead birds or squirrels that may have been infected with the virus.
Only use mosquito repellent that is approved for use in pets to prevent bites. Check the label to determine if the product is safe for pets, or ask your veterinarian for a recommendation. Many insect repellents that are designed for human use contain a chemical that can cause serious illness in pets.
In the event that pesticides are sprayed in your area, make sure to keep pets indoors during spraying.
Copyright © 2009, American Animal Hospital Association
Reprinted with permission from the American Animal Hospital Association.