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Canine Influenza

Canine influenza is a new virus, first appearing in 2004. The virus evolved from an equine influenza virus and is classified as H3N8 strain of flu. This virus is not contagious to humans or other species.
Nearly all dogs exposed will become infected, with 80% showing some signs of illness such as coughing, nasal discharge, and fever. Only 1-5% will become seriously ill or die from complications such as pneumonia. The symptoms are nearly indistinguishable from other upper respiratory infections and kennel cough. It is spread from dog to dog by aerosol (coughing) or by direct contact with sick dogs or contaminated objects. Almost all dogs that have been infected have been in kennels, shelters, racetracks, or shows. Outbreaks have occurred in about 30 states, including Wisconsin.
A vaccine is available for at-risk dogs over 6 weeks of age. The vaccine is made from a killed virus, so it requires 2 doses, 2-3 weeks apart, and the best protection occurs about a week after the second dose. Annual boosters may be needed if the dog continues to be at risk.
If you suspect your dog has come down with the canine flu, testing can be done to confirm illness (along with other respiratory infections) during the first 4 days of symptoms. Otherwise treatment is usually limited to supportive care (rest, plenty of water, etc.) while the patient’s immune system responds to the virus. In more severe cases, especially where pneumonia or other secondary infection is present, IV fluids and antibiotics may be necessary. Rare cases may require hospitalization for oxygen and/or nebulization. It also important to keep your dog at home and away from other dogs to prevent spread of the virus.

Contact Hallett Veterinary Hospital if you any questions or concerns about canine influenza.

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