Canine influenza, also known as dog flu, has been in the news lately, following an outbreak of the virus that has affected over 1000 dogs in the Chicago area, killing 5 dogs. Canine Influenza Virus (CIV) is a very contagious virus that began in horses before spreading to dogs. Canine influenza, caused by this virus, is not typically fatal, and with treatment, the dog can recover fully within a week to a month. However in most severe cases (less than 10% of dogs who contract it), CIV can lead to high fever, pneumonia and death. Similar to our previous post on Parvovirus, we have pulled together some facts about canine influenza, how it’s spread, symptoms and treatment.

How is canine influenza spread?

As mentioned above, CIV is very contagious, and can spread from dog to dog through shared food bowls, toys or even the air around them. As a result, outbreaks often occur in places where numerous dogs come in contact with each other, including kennels, dog day cares and dog parks. Even though it is highly contagious, CIV does not live long in the environment, so isolation of infected dogs and a thorough cleaning of the shared area can help limit its spread. (Note: According to the CDC, “there is no evidence of transmission of canine influenza virus from dogs to people.”)

What are the symptoms of canine influenza? How is it treated?

Symptoms of canine influenza include:

  • Coughing
  • Sneezing
  • Runny nose, with a yellow-green discharge
  • Lethargy
  • Loss of Appetite
  • In rare cases, fever and onset of pneumonia

It may take up to 10 days after exposure to CIV for symptoms to manifest. Some of these symptoms are similar to bordetella or kennel cough, however canine influenza often results in a “more moist cough than bordetella’s dry cough.” If your dog develops these symptoms, a visit to vet is recommended as soon as possible.  The vet will also recommend that you keep your door indoors and away from other dogs until they can determine the cause and begin treatment.

Treatment of the milder form of canine influenza (again, this is the form that most cases take) includes rest, fluids and sometimes medication. The severe form often requires hospitalization. Again, dogs with canine influenza should be isolated from other dogs until they recover.

How can you prevent canine influenza?

“Preventing canine influenza or any other “kennel cough” relies on the same principles as humans trying to avoid the common cold,” writes veterinarian Dr. Ingrid Pyka. “Prevention depends on minimizing exposure to the virus.” This is not an easy thing to do, especially due to the fact that an infected dog may not show symptoms right away.

So should you avoid all possible hot spots like kennels, groomers and dog parks at all times? That doesn’t seem feasible, nor acccording to the AVMA, it is required, unless there is an established outbreak (like the one taking place in Chicago this month). The AVMA writes:

Dog owners should be aware that any situation that brings dogs together increases the risk of spread of communicable illnesses. Good infection control practices can reduce that risk, so dog owners involved in shows, sports, or other activities with their dogs or who board their dogs at kennels should ask whether respiratory disease has been a problem there, and whether the facility has a plan for isolating dogs that develop respiratory disease and for notifying owners if their dogs have been exposed to dogs with respiratory disease.

As long as good infection control practices are in place, pet owners should not be overly concerned about putting dogs in training facilities, dog parks, kennels, or other areas frequented by dogs.

There is also a canine influenza vaccine available, in addition to the “core” vaccines provided by your vet. Your vet may recommend this vaccine if your dog is at increased risk for the disease due to various factors (frequent kennel boarding, recent outbreak in the area, and others).

UPDATE: On April 12, 2015, researchers at Cornell University reported:

“The canine influenza outbreak afflicting more than 1,000 dogs in Chicago and other parts of the Midwest is caused by a different strain of the virus than was earlier assumed, according to laboratory scientists at Cornell University and the University of Wisconsin. Researchers at Cornell say results from additional testing indicate that the outbreak is being caused by a virus closely related to Asian strains of influenza A H3N2 viruses, currently in wide circulation in southern Chinese and South Korean dog populations since being identified in 2006.”

One key difference between the two strains is that H3N2 has caused infection and respiratory illness in cats. For more information about these new findings, read this article from Cornell University.

For more information about canine influenza, contact your veterinarian. To read more about canine influenza, its history and how it’s treated, here are some online resources:

Canine Influenza FAQs from the American Veterinary Medical Association (AVMA)

Key Facts about Canine Influenza (Dog Flu) from the Centers for Disease Control and Prevention (CDC)

Canine Influenza Virus/Canine Flu article from ASPCA


Image Credit: “Hans” by Aaron Jacobs is licensed under CC BY-SA 2.0. Image is cropped.