You may have heard in the news about a recent outbreak of canine influenza. Here are some commonly asked questions and answers regarding this disease…

Q: What is canine influenza?

A: Canine influenza (CI), or dog flu, is a highly contagious respiratory infection of dogs that is caused by an influenza A virus. The canine influenza virus (CIV) is closely related to the virus that causes equine influenza and it is thought that the equine influenza virus mutated to produce the canine influenza virus. In the U.S., canine influenza has been caused by the H3N8 influenza A virus. A separate canine influenza virus, H3N2, had been reported in Korea, China and Thailand, but not in the U.S. until 2015, when an outbreak in Chicago, IL was determined to be caused by the H3N2 strain.

Two clinical syndromes have been seen in dogs infected with the canine influenza virus—a mild form of the disease and a more severe form that is accompanied by pneumonia.

Mild form — Dogs suffering with the mild form of canine influenza develop a soft, moist cough that persists for 10 to 30 days. They may also be lethargic and have a reduced appetite and fever. Sneezing and discharge from the eyes and/or nose may also be observed. Some dogs have a dry cough similar to the traditional “kennel cough” caused by Bordetella bronchiseptica/parainfluenza virus complex. Dogs with the mild form of influenza may also have a thick nasal discharge, which is usually caused by a secondary bacterial infection.

Severe form — Dogs with the severe form of canine influenza develop high fevers (104ºF to 106ºF) and have clinical signs of pneumonia, such as increased respiratory rates and effort. Pneumonia may be due to a secondary bacterial infection.

Because this is still an emerging disease, almost all dogs, regardless of breed or age, are susceptible to infection and have no immunity. Virtually all dogs that are exposed to the virus become infected and nearly 80% show clinical signs of disease. Fortunately, most affected dogs have the mild form.

Q: Do dogs die from canine influenza?

A: Fatal cases of pneumonia resulting from infection with canine influenza virus have been reported in dogs, but the fatality rate is low (less than 10%). Most dogs with CI recover in 2-3 weeks.

Q: How is a dog with canine influenza treated?

A: As with any disease caused by a virus, treatment is largely supportive. Good animal care practices and nutrition assist dogs in mounting an effective immune response. The course of treatment depends on your pet’s condition, including the presence or absence of a secondary bacterial infection, pneumonia, dehydration, or other medical issues (e.g., pregnancy, pre-existing respiratory disease, compromised immune system, etc.). Your veterinarian might prescribe medications, such as an antibiotic (to fight secondary infections) and/or a nonsteroidal anti-inflammatory (to reduce fever, swelling and pain). Deyhdrated pets may need fluid therapy to restore and maintain hydration.  Other medications, or even hospitalization, may also be necessary for more severe cases.

Q: Is canine influenza virus transmissible from dogs to humans?

A: To date, there is no evidence of transmission of canine influenza virus from dogs to people.

Q: Do I need to be concerned about putting my dog in day care or boarding it at a kennel?

A: 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 of early April, there are no cases that have been identified in Michigan. However, as tourist season approaches the likelihood of this significantly increases. When possible, please avoid taking your dog to areas where many dogs congregate and avoid contact with unfamiliar dogs.

Q: My dog has a cough…what should I do?

A: Consult your veterinarian. Coughing can be caused by many different medical problems, and your veterinarian can examine and evaluate your dog and recommend an appropriate course of treatment. If canine influenza is suspected, treatment will usually focus on maximizing the ability of your dog’s immune system to combat the virus. A typical approach might include administration of fluids if your dog is becoming dehydrated and prescribing an antimicrobial if a secondary bacterial infection is suspected.

Canine influenza virus can be spread via direct contact with respiratory secretions from infected dogs, and by contact with contaminated inanimate objects. Therefore, dog owners whose dogs are coughing or exhibiting other signs of respiratory disease should not participate in activities or bring their dogs to facilities where other dogs can be exposed to them. Clothing, equipment, surfaces, and hands should be cleaned and disinfected after exposure to dogs showing signs of respiratory disease to prevent transmission of infection to susceptible dogs. Clothing can be adequately cleaned by using a detergent at normal laundry temperatures.

Q: What diagnostic tests will tell me whether a dog has canine influenza? What samples do I send? Where do I send the samples? How do I distinguish between canine influenza and kennel cough?

A: Canine influenza cannot be diagnosed solely by clinical signs because the clinical signs (coughing, sneezing and nasal discharge) are similar to those associated with all of the other respiratory pathogens and cannot be differentiated from them. The most reliable and sensitive method for confirmation of infection is blood testing, ideally taken within the first 7 days of illness. If a dog has been ill for less than 4 days, nasal swab may be taken.

Q: Is there a vaccine?

A: The first vaccine for H3N8 canine influenza was approved in 2009, and there are several H3N8 canine influenza vaccines available. At this time, there is not an H3N2 vaccine available in the U.S. It is not known at this time whether the H3N8 vaccine will offer any protection against the H3N2 strain. Vaccination against other pathogens causing respiratory disease may help prevent more common respiratory pathogens from becoming secondary infections in a respiratory tract already compromised by influenza infection.

*Adapted from the AVMA FAQ information sheet.*

 
*Revised 4/20/15. Information is subject to change as more is learned about this influenza virus.*