Canine influenza is a potentially deadly disease that causes high fever, coughing, and pneumonia in severe cases in dogs, and sometimes, even cats. At this point, it is not known to cause infection in humans, although it is somewhat similar to human influenza viruses. The newest strain, called H3N2, has been diagnosed in dogs in North Carolina, and while not common, poses a significant threat if your dog happens to become exposed.
Dogs that travel for competition, work, or other activities, dogs adopted from shelters, and dogs that stay in boarding kennels or dog day care facilities may also be more at risk for this reason. Your dog does not have to come in direct contact with other dogs to become exposed as the virus can travel in the air and on objects such as clothing, shoes, leashes, and other training equipment.
Two strains of influenza have been recognized in dogs the United States over the past 15 years. The first, H3N8 strain was first recognized in racing Greyhounds in Florida around 2004 and while causing an initial scare in the canine sports and competition fields, eventually decreased in occurrence to the point where it occurs very infrequently now. Because of this, when the newer and more dangerous strain H3N2 was introduced to the U.S. in 2015, many people were less alarmed because the term “canine influenza” had essentially lost it’s fear factor. There was a thought among dog owners that since H3N8 had not caused the country-wide problems they had feared, that this was just another round of the same thing, and no cause for worry. In fact, the H3N2 strain is thought to be more virulent (causing worse disease), and sheds longer in infected dogs than the H3N8 strain. In short, it’s not something to dismiss as “not really a problem!”
The first reported outbreak of the H3N2 strain in the United States occurred in Chicago, and was traced to dogs imported from South Korea by a canine rescue group. From there, it has spread to dogs across the United States, including North Carolina. Many North Carolina Boarding Kennels and canine event locations are now requiring proof of vaccination against canine influenza in order to use their services.
Best practices for prevention include having your dog vaccinated against canine influenza virus (CIV) using a “bivalent” vaccine that covers both H3N8 and the newer, more dangerous H3N2 strain. Older vaccines only offered protection against the less threatening H3N8 strain. When seeking out vaccination for your dog, ask your veterinarian to make sure they have the “bivalent” vaccine. Dogs as young as 7-8 weeks can safely receive this vaccination. As with any medication, there can be minor side effects such as soreness at the injection site for a day or two, but major side effects have not been commonly reported. Dogs receive an initial vaccination and one booster two to four weeks later, then a vaccination once a year after that. In some dogs, vaccination does not completely prevent them from getting the disease, but can significantly lessen the seriousness of the infection. That is, they may show some signs of infection, but not nearly as bad as if they had not been vaccinated, and the chances of dying from the infection are also significantly reduced. And unlike the human influenza vaccines, there are far fewer known strains in dogs compared to people so the strain the vaccination protects against does not have to be predicted each year. That means the chance of your dog being vaccinated against the “right” strain is almost guaranteed with the bivalent vaccine.
Other best practices include isolating newer dogs in quarantine in kennels for 2-4 weeks prior to introducing them to the general kennel area if possible, which we understand is not practical in many cases. Seek veterinary care for any dog that shows signs of coughing, lack of appetite, or decrease in their normal amount of energy or enthusiasm for work or play. Wash bowls and equipment frequently with soap and hot water to inactivate the virus, and if possible, after handling any sick dog, change clothes and wash your hands before handling other dogs.
Unless there is a known current outbreak in your area, threat of canine influenza virus should not make you avoid enjoying competitive or recreational activities with your dog, or concerned about boarding in facilities that practice good sanitation and require vaccination for their boarders. But since outbreaks cannot easily be predicted and early signs of illness may be missed in some dog at these locations, vaccination against both strains of canine influenza virus is your best method of prevention at this time. And if you are planning on adopting a new dog from a shelter or rescue organization, protect your current dogs with vaccination 3-4 weeks before bringing your new dog into your home to ensure they are well protected.