Flu hits dogs, too - Canine influenza virus is a concern in Colorado

Think all of the scary icky things are so last month? Think again. People are lining up for their flu shots. Consider one for your dog, too. Dog flu outbreaks have occurred in Denver and other areas of Colorado.

Dog flu refers to a specific Type A influenza virus that infects dogs, not humans. People are familiar with the notation H1N1 for swine flu; canine influenza virus is represented as H3N8. It originated in horses and spread to dogs; it can now be spread between dogs. Canine influenza virus (CIV) is now considered separate from the H3N8 equine influenza.

The symptoms of canine influenza include a runny nose, cough, loss of appetite, lethargy (tiredness), and fever. A small number of dogs can develop more severe disease, which is characterized by the development of pneumonia. Some dogs can be infected and show no symptoms. While this is a fairly new disease in dogs and all dogs are susceptible to infection, about 80% of those infected develop mild disease.  Only a very small number of those infected die.

Canine influenza virus is spread through respiratory secretions from infected dogs. Dogs can have contact with contaminated objects or with people who move between infected and uninfected dogs. Dog owners whose dogs show symptoms of respiratory illness, such as coughing or runny nose, should keep their dogs away from other dogs and common shared areas to prevent other dogs from being exposed to the virus. Dog day care and boarding facilities should be especially aware of dogs displaying symptoms. All surfaces, equipment, toys, clothing, dishes, and people’s hands should be cleaned and disinfected after contacting dogs that might have CIV to avoid cross-contamination.

If your dog has a cough, especially if it has been around other dogs recently and has been vaccinated for Bordetella, take it to your veterinarian for evaluation. While the Bordetella vaccine does not protect dogs against CIV, it is a reasonable guess that a coughing dog vaccinated against Bordetella is likely to have CIV. There is a test for CIV. One test uses respiratory secretions at the time the dog is sick (showing symptoms). The other test uses two blood samples; one is collected at the time of illness and the other is collected two to three weeks after disease onset. The results will help your veterinarian determine what kind of treatment to give your dog.

Treatment for mild CIV infection consists of keeping the dog comfortable and hydrated (sometimes with intravenous or subcutaneous fluids). This allows the dog’s immune system to mount an attack to the virus. If necessary, your veterinarian might prescribe diuretic medications to drain fluid from the dog’s lungs. Your veterinarian may also recommend broad-spectrum antibiotics to prevent or treat a secondary bacterial infection. If a dog’s immune system is already compromised, such as by fighting the viral infection, it is easier for bacterial infections to set in. The development of secondary bacterial pneumonia is one of the most serious risks of CIV infection.

There is no evidence yet that CIV can be transmitted to humans and there is not a single case reported of a human being infected with CIV. However, the CDC is watching the CIV and new cases of human influenza infection very carefully. It is considered a low risk to humans.

Please read: Canine influenza virus vaccine - what is it and does your dog need it?