Canine influenza virus (CIV) is one of the viral causes of kennel cough, and this highly contagious respiratory disease has recently affected thousands of dogs in the U.S., particularly the Midwest region where dog parks, groomers, and pet daycare/boarding facilities have been forced to close temporarily to decrease the spread of infection. Because there have been no reported cases of CIV in the country until this year, canines here have never been exposed, putting dogs of all ages, breeds, and with previous immunizations at risk.


While most dogs will show typical signs of kennel cough, for some it could develop into secondary complications such as pneumonia. When treated quickly, the fatality rate of CIV is low, however the levels of severity can vary. Seek immediate veterinary care if your dog shows any of these symptoms:

  • Persistent coughing
  • Sneezing
  • Variable fever
  • Clear nasal discharge that progresses to thick, yellowish-green mucus
  • Rapid/difficult breathing
  • Loss of appetite
  • Lethargy
Testing & Diagnosis:

To identify the cause of the infectious disease, Merck Animal Health sponsored a diagnostic sampling program. Nasal and pharyngeal swabs were sent to Cornell University Veterinary Diagnostic Laboratory. From March 16 through April 7, 131 dogs tested positive for Canine Influenza through PCR. Many samples are still pending final results.

Preliminary reports on the gross necropsy of a confirmed Canine Influenza case showed widespread and severe damage to the lung tissue and hemorrhagic pneumonia. Histopathology is pending in that case.


The Nobivac Canine Flu H3N8 vaccine has been shown to protect dogs against CIV infection by significantly decreasing clinical signs, reducing viral shedding, and reducing CIV-induced lung consolidation. The vaccine is given subcutaneously and a booster is needed two to four weeks after the initial dose.

Consult your veterinarian once symptoms occur to discuss the best treatment approach for your dog’s condition.

In addition, good nutrition to raise immunity and a warm, comfortable place to rest will aid in a quick recovery.

If your dog is showing signs of canine influenza virus, seek veterinary treatment immediately. VETMED’s emergency services are available 24 hours a day, 7 days a week. Call (602) 697-4694 to make an appointment or to let us know you’re on the way.