Search Menu

The dog flu has been in the media recently, thanks to increased reports of outbreaks and new strains. While most cases of dog flu are not fatal, the canine influenza virus can make your dog uncomfortably sick, causing him—and you—a lot of stress and time spent at the vet’s office. If you are a dog owner, you don’t need to panic about the dog flu. You should, however, familiarize yourself with the symptoms of dog flu so that you know what to look for in the event of an outbreak in your area.


What Is the Dog Flu?

The dog flu, or canine influenza virus, is an infectious respiratory disease caused by an influenza A virus, similar to the viral strains that cause influenza in people. There are two known strains of dog flu found in the United States:

  • H3N8
  • H3N2

The H3N8 strain actually originated in horses. The virus jumped from horses to dogs to become a canine influenza virus around 2004, when the first outbreaks affected racing Greyhounds at a track in Florida, and the virus is now found in 40 states in the U.S.

H3N2, on the other hand, originated in Asia, where scientists believe it jumped from birds to dogs. H3N2 is the virus responsible for the 2015 and 2016 outbreaks of canine influenza in the Midwest and continues to spread throughout the United States.


How Is Canine Influenza Spread?

Like human forms of influenza, dog flu is airborne. Respiratory secretions escape into the environment in the form of coughing, barking, and sneezing, where they are then inhaled by a new canine host. The dog flu also spreads through contaminated objects and environments, like water bowls, collars, and kennel surfaces, or through contact with people who have had direct contact with an infected dog.

dog flu chihuahuas

Crowded areas like kennels and dog parks are breeding grounds for diseases like canine influenza. The close proximity of the dogs means that a barking, coughing, or sneezing dog can easily infect the dogs around him. This is made more dangerous by the fact that dogs are most contagious during the incubation period before they start exhibiting symptoms.


How Long Are Dogs Infected With Dog Flu Contagious?

The incubation period of canine influenza is approximately two-to-four days from initial exposure to the dog flu virus. Viral shedding starts to decrease after the fourth day, but dogs with H3N8 remain contagious up to 10 days after exposure, and dogs with H3N2 remain contagious for up to 26 days. Most vets recommend isolating dogs with H3N2 for at least 21 days to reduce the risk of transmission.

Almost all dogs that come into contact with the disease will contract it, but not all dogs that become infected show symptoms of the virus. About 20-25 percent of dogs infected are asymptomatic, but these dogs can still spread the disease. If one of your dogs catches the dog flu and the other seems unaffected, remember that he could still have the virus. Talk to your vet about quarantine procedures for all of the dogs in your household.


Symptoms of Dog Flu

So how do you know if your dog has the dog flu? There are several symptoms of dog flu that all owners should be aware of. Dog flu cases range from mild to severe and, unlike human influenzas, are not seasonal. Keep an eye out for the following symptoms year-round:

  • Coughing (both moist and dry)
  • Sneezing
  • Nasal discharge
  • Purulent nasal discharge
  • Runny eyes
  • Fever
  • Lethargy
  • Difficulty breathing

Dog flu symptoms resemble kennel cough symptoms, which is also an illness that you should talk to your veterinarian about as soon as you notice symptoms.

dog flu sick dog

Most cases of dog flu are mild, but severe cases do occur. In these cases, dogs develop pneumonia, difficulty breathing, and a high fever. Luckily, the mortality rate of dog flu is relatively low, with less than 10 percent of dog flu cases resulting in fatalities.

This does not mean that you should refrain from taking your dog to the vet, as secondary infections can develop as a result of the virus. And as anyone who has had the flu can attest, the experience is singularly unpleasant, and your veterinarian can help you keep your dog comfortable during the recovery process.

Learn more about the symptoms of kennel cough


Treating Dog Flu

The canine influenza virus requires the attention of a veterinarian. In some states, vets are required to report cases of canine influenza to the government to help monitor the spread of the disease. Since the canine influenza is still a relatively new virus, you will actually be assisting your veterinarian, as well as your dog, by bringing your sick dog in for a visit. This will help veterinarians study and monitor the disease as it evolves.

There is no cure for dog flu. Treatment is supportive, and your veterinarian can advise you on the best ways to keep your dog comfortable during his illness and recovery. Some dogs may require fluids to aid their recovery, as well as nonsteroidal anti-inflammatory medications to reduce their fevers. Your vet will help you come up with a nutritional plan and may prescribe antibiotics to treat secondary bacterial infections.

Your vet will also inform you about appropriate quarantine procedures to prevent the spread of dog flu, depending on the strain of the virus your dog contracts, and can give you information about disinfectant solutions to use in your home to help kill the virus.

dog flu vet

Call your vet ahead of time to let her know that your dog is showing symptoms of a respiratory infection. Both kennel cough and dog flu are highly contagious, and your vet may request that you keep your dog in the car (with someone keeping the car running to prevent overheating, of course) until your appointment time to prevent the risk of transmission to other patients in the waiting room.


Preventing Dog Flu

The best way to prevent your dog from contracting the dog flu is to keep him away from public places or kennels with recently reported cases of dog flu. If you come into contact with a dog that you suspect has dog flu or has recently been exposed to the dog flu, wash your hands, arms, and clothing before touching your own dog. This will reduce the risk of transmission from you to your dog.

There are vaccines available for both the H3N8 and H3N2 strains of canine influenza. Your vet may recommend the vaccine based on your lifestyle. For instance, if you live in an area with a high incidence of dog flu or if your dog regularly spends time in kennels or travels to shows around the country, then your dog could be at an increased risk of contracting canine influenza and your vet may recommend the vaccine as a precaution.

It is up to us to keep our dogs safe and our dog-friendly community venues free from contagious diseases. The more dog owners who are aware of the symptoms of dog flu, the better the chances are of veterinarians identifying another outbreak before it gets out of control.

Note: The information provided here is not meant as a substitute for veterinary care. If you suspect that your dog has the dog flu or another respiratory infection, contact your veterinarian as soon as possible and refrain from taking your dog to public places where you might expose other dogs to illness.


Our Gift to You

Download Now

Emergency First Aid for Dogs

Even the most responsible pet owner can't always protect their pet from a sudden accident or illness. Getting your pet immediate medical attention can be the difference between life and death. Download this e-book to learn more about what to do in an emergency situation.