Canine Influenza (Dog Flu) Frequently Asked Questions

What is dog flu?

Dog flu is a contagious respiratory disease. It is caused by two specific Type A canine influenza viruses (CIVs): H3N8 and H3N2.

What is the new subtype of CIV?

The “new” CIV, H3N2, was identified in South Korea in 2006 and has been reported in several Asian countries. It was first identified in dogs in the U.S. in April 2015. (CIV H3N8 was first identified in dogs in the U.S. in 2004.) The first CIV H3N2 vaccine in the U.S. was introduced by Zoetis in November 2015.*

What are the symptoms of dog flu?

As with flu in humans, symptoms and symptom severity may vary from dog to dog. Symptoms of CIV H3N2 are similar to those of CIV H3N8. They may include reduced appetite, high fever, cough, runny nose and lethargy. Symptoms can persist for several weeks.

Dogs with CIV H3N2 may show more severe signs than dogs with CIV H3N8—or they may show no signs at all. Only diagnostic testing can distinguish which type is present.

If you have any concerns that your dog may be showing signs of dog flu, contact your veterinarian.

Is dog flu a very serious illness?

Both CIV H3N2 and CIV H3N8 are contagious, and dogs exposed to dog flu may become infected. About 80 percent of infected dogs will show clinical signs. Severity—and the clinical signs themselves—will vary from dog to dog.

Both types can be a more serious illness for certain groups of dogs, including very young, very old or immunocompromised dogs. The mortality rate for dog flu in general is less than 10 percent. Your veterinarian can talk with you about your pet’s individual risk of infection.

Source: Canine Influenza FAQ. American Veterinary Medical Association. Accessed March 21, 2016.

My dog has been vaccinated against CIV H3N8. Does that vaccine also help protect against CIV H3N2?

The CIV H3N8 vaccine will not offer cross-protection against CIV H3N2, which has a separate vaccine. Although flu vaccines greatly reduce the likelihood that a dog will contract flu, just like other canine respiratory vaccines, they cannot eliminate the possibility of infection. Flu shots also can be ineffective against unanticipated CIV types.

How is dog flu transmitted?

Both types of dog flu can be passed from dog to dog in some of the same ways we pass flu among ourselves. Dogs can even spread the virus before they display any clinical signs of disease. Droplets from sneezing or coughing and contact with contaminated objects are the main culprits. The virus also can survive on human skin—and for at least a day on clothing—so we can transmit the virus to dogs, too.

Source: Canine Influenza FAQ and Canine Influenza Backgrounder. American Veterinary Medical Association. Accessed March 21, 2016.

Is there a vaccine available for CIV H3N2?

Yes, Zoetis has released the first vaccine for CIV H3N2,* available through your veterinarian, which helps protect your dog from outbreaks. Indicated for vaccination of healthy dogs 8 weeks of age or older as an aid in the control of disease associated with CIV H3N2 infection, the vaccine is recommended for dogs in regular contact with other dogs at public or private facilities or events.

For veterinarians: vaccine information»

What else can I do to keep my pet safe?

If there is a dog flu outbreak in your area, be aware that risk of exposure to the virus may be increased at dog parks, doggy day care centers, communal water bowls and in other settings where dogs share toys and come into close contact with each other. Wash your dog’s toys, bowls and bedding regularly. When you’ve come into contact with other dogs, wash your hands thoroughly before handling your own pet. Avoid contact with other pets, as the virus can persist on clothing and other surfaces for at least 24 hours. Ask your veterinarian about vaccinating your dog for CIV H3N2.

Source: Canine Influenza Backgrounder. American Veterinary Medical Association. Accessed June 2, 2015.

What can I do to keep other pets safe?

If you are concerned that your dog may be showing signs of dog flu, contact your veterinarian and keep your dog at home. Until you’ve received examination or test results from your veterinarian, keep your dog separated from other pets. Wash your hands thoroughly after handling your own pet. Vaccinating your dog may also help keep other dogs safe if there is a risk of a dog flu outbreak in your area.

Can humans catch dog flu?

There is no evidence that either CIV H3N2 or H3N8 can be transmitted to humans.

What is Canine Infectious Respiratory Disease (CIRD), and what does it have to do with dog flu?

CIRD refers to many different bacteria and viruses that can cause respiratory disease in dogs. On the basis of symptoms alone, it generally is impossible to determine which of those pathogens is causing disease. There are vaccines that help protect against many of the pathogens that can lead to CIRD, including CIV H3N2 and H3N8.

Dog-to-dog contact or contaminated objects can spread CIRD. Environmental factors (such as dog parks) and host-related factors (such as a dog’s overall health) also can play a part in the development of CIRD.

What treatments are available for dog flu?

As a viral infection, dog flu cannot be cured with medication. Supportive care, such as making sure a pet is resting, eating and staying well hydrated, can help ease some symptoms and help prevent worsening of others. Sometimes antibiotics also are given to treat or guard against secondary bacterial infections. Your veterinarian can talk with you about specific treatment options for your pet’s symptoms.

Keep dogs and cats with signs of respiratory infection away from other pets until your veterinarian tells you otherwise.

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