Canine Influenza - a Highly Contagious Upper Respiratory Disease

Canine Influenza, known as H3N8, a particular sub-type of the influenza A virus, was discovered in 2004 in Florida stemming from a large viral outbreak affecting the racing greyhound population in January of that year. By the end of 2005, H3N8 was identified as an emerging viral pathogen also known as the dog flu. The H3N8 virus has since become somewhat established in the domestic dog population in at least 30 states.

Prior to the outbreak at the Florida racetrack, the H3N8 influenza strain had been an equine influenza and was well known for at least the last 40 years. The jump of the H3N8 influenza stain from horse to dog took some detective work to uncover, but was accomplished rather quickly due to the collaborations by individuals and colleagues from the Influenza Branch of the CDC, Cornell University, the University of Wisconsin College of Veterinary Medicine, and the Auburn University College of Veterinary Medicine. Dr. Ed Dubove from Cornell is widely respected as a main contributor to the discovery of the new dog influenza virus.

Fortunately, the H3N8 virus has a low mortality rate in our canine population, but it can cause more serious problems if left untreated. The disease mimics the bacterial respiratory disease known as the 'kennel cough' syndrome, which could delay a diagnosis of the influenza. Our dog population has not built up any immunity to this new disease yet, so it is highly contagious and can spread very rapidly. The dog flu also spreads much the same way as human flu.

Symptoms of the dog flu consist of a cough with nasal discharge, and very likely a temperature which can reach up to 106 degrees. It is a good idea to suggest checking for the canine influenza to your veterinarian if these symptoms emerge and kennel cough is the single diagnosis. Only a small percentage of dogs have more serious complications such as pneumonia from the dog flu, leading to hospitalization and possibly death. The disease can retreat completely with early detection, which is critical, and treatment with the appropriate antibiotics and fluids

The CDC also stresses that the dog flu does not cross over to humans, as has been rumored on the internet. However, if you have a multiple dog family, lots of dogs in your neighborhood or a lot of social dog events, it is extremely important to identify the canine flu early and isolate the patient to keep from infecting the other dogs in the household.

In June of this year, the first canine influenza vaccine was approved by the United States Department of Agriculture (USDA) Animal and Plant health Inspection Service (APHIS). At this time the vaccine is not considered a requirement for all dogs and it does not prevent the dog flu, but it is successful at reducing the severity of the symptoms, which aids in slowing down the spread of the disease. It is extremely useful for dogs kept in the 'high density' situations such as shelters, racing kennels, dog shows, boarding kennels and doggie daycare, where the dog flu is most likely to occur. The vaccine requires two shots 2-4 weeks apart and it's now available at veterinary offices.

1. Center for Disease Control
2. Wikipedia
3. http://eamuskogee.com