As a provider of your pet’s care, we would like to highlight the emergence of canine influenza—a highly infectious disease that is occurring with increasing frequency in our area and across the country.

Our objective is to inform and educate pet owners about the sources, symptoms, severity and treatment of this emerging health issue. Our objective is not to be alarmists, but realists by sharing facts and effective preventative measures.

Wellness Focus
Just like people, healthy pets sometimes fall ill. Our priority is to help maintain the wellness of your pet—taking proactive measures to avoid illnesses and to keep your pet happy.


Healthy Pets

In this spirit, it is important that you carefully review this newsletter so you are aware of the risks, symptoms, transmission methods, preventative measures and treatment associated with canine influenza.

Because canine influenza (or dog flu) is relatively new, dogs have no natural immunity and it is therefore highly contagious to them. This flu can cause serious harm and discomfort to your dog, and in certain circumstances, it can be fatal.

Canine influenza is caused by an influenza A virus with two particular strains, H3N8 and H3N2.

The H3N8 strain was first recognized in Florida during 2004 when it appeared to adapt from horses to greyhounds and emerge as a new canine-specific virus. Since 2004, this strain has been documented in a growing number of U.S. states.

The H3N2 strain was first recognized in Asia in 2006 and is believed to have adapted from birds to canines. In 2015 the first U.S. outbreak appeared in Chicago and quickly spread to more than 25 states by the end of the year. This strain is of greater concern given its longer contagion period of up to 24 days.

While highly contagious among dogs, there is no evidence that either strain can be transferred to people, cats or other species.

Similar to the flu that impacts people, a dog infected with canine influenza will likely show respiratory symptoms that may include:

  • Moist or dry cough lasting for several and up to 30 days
  • Sneezing
  • Runny nose or greenish nasal discharge
  • Eye discharge
  • Rapid or labored breathing
  • Lethargy or a desire not to eat (or weight loss)
  • High fever (104-105°F) or pneumonia


Canine Influenza
The incubation period is generally two to four days from exposure (prior to exhibiting symptoms)—and it is this period when they are the most contagious. Dogs can spread the virus for up to 24 days if infected with the H3N2 strain.

Upon onset, a veterinarian can diagnose the disease via a blood test or the use of a nasal or throat swab.

Unless vaccinated, nearly all of the dogs exposed to canine influenza will become infected. And while 80% will show signs of the disease (20% will show no signs), all exposed dogs can help spread the virus. As there is no canine “flu season,” dogs can contract influenza year round.

Canine influenza is highly contagious and is spread via:

  • Coughing, barking and sneezing and other airborne respiratory secretions from an infected dog (even if they themselves are not showing signs)
  • Contaminated objects such as toys, kennel surfaces, food and water bowls, collars and leashes
  • People moving between infected and uninfected dogs

The virus can also be transmitted via surfaces for up to 48 hours, on clothing for 24 hours and on hands for up to 12 hours.


By far, the best approach to reducing the chance of your dog becoming infected with the canine flu is to have them vaccinated—particularly for younger dogs, older dogs or those who tend to visit areas of high potential infection such as dog parks, kennels or areas of high dog concentration. While no vaccine can prevent every dog from being impacted by the flu, vaccinations can help limit the severity if your dog contracts the virus.

Another key to prevention is isolation. As with people, it’s best to keep potentially infected dogs away from each other (in separate rooms) and prevent the sharing of bowls, toys, beds or other items.

Of course, good human and canine hygiene is vital to limit the chance of spreading the disease—washing hands, wiping footwear and washing bedding.

If you believe your dog may be exhibiting any of the flu symptoms above, immediately separate your dog from others and please contact us. As with other health issues, early detection and diagnoses can help lead to a faster and more comfortable recovery.

As for all viral diseases, treatment is largely supportive–meaning there is little that can be done to directly lessen the impact of the disease. Good care and nutrition may assist dogs in mounting an effective immune response to the disease.

Most dogs recover from canine influenza within two to three weeks. However, the presence of secondary bacterial infection, pneumonia, dehydration or other health factors (e.g., pregnancy, pre-existing pulmonary disease, immunosuppression, tracheal collapse, etc.) may require additional tests and treatments including antimicrobials, anti-inflammatory medications and fluids.

Pet Boarding
If you plan to board your pet at a kennel, you should not be surprised if their reservation is only honored if your dog has been vaccinated. There are pet boarding facilities that may require every dog to be vaccinated to help limit the spread of the disease and, of course, to help maintain the health of pets.