Canine Influenza

By Dr. Karen Burgess

What is Canine Influenza?
Canine Influenza is a virus that primarily affects a dog’s respiratory system causing a cough, fever, and in some cases pneumonia. The infection is often difficult to differentiate from other more common causes of respiratory disease in dogs (i.e. kennel cough).

How common is Canine Influenza diagnosed?
First diagnosed at Greyhound racetracks in 2004, Influenza has subsequently been diagnosed sporadically in pockets throughout the United States. The occurrence is much less frequent in nature than other causes of “kennel cough” or infectious respiratory disease. In spring 2015 there was an increase in respiratory disease seen in downtown Chicago; several of these cases tested positive for Canine Influenza. It is important to remember that while the broadcast news may report “thousands affected” this has not been confirmed and many of these cases may in fact be from other more common causes of kennel cough.

How is Canine Influenza spread?
The virus is spread in respiratory secretions that have been aerosolized or landed on objects that another dog then comes in contact with. Canine Influenza is highly infectious with 80% of exposed dogs developing some form of infection. The 20% that do not become infected can however still spread the disease. Group dog situations (daycare, boarding, dog classes, dog parks, veterinary hospitals) are more apt to encourage the spread of the disease. Objects used with or by infected dogs (bowls, grooming utensils, leashes) can also spread infection.

What are the symptoms of Canine Influenza?
Most dogs infected with Canine Influenza develop minimal signs of a persistent cough lasting for two to three weeks. Nasal discharge, loss of appetite, fever, breathing difficulties, and pneumonia may develop in more severely affected patients. It is thought that the very young and very old are more susceptible. In rare cases, infection and its subsequent complications may be fatal. Any pet that develops signs of an upper respiratory infection that has been recently exposed to other dogs in particular in an area where an outbreak is or has occurred would be considered at higher risk for infection.

How is Canine Influenza treated?
For most dogs, at home care with possible antibiotics and cough suppressants is sufficient. For more severely affected patients, hospitalization for fluid therapy, injectable antibiotics, and oxygen therapy may be necessary.

How is Canine Influenza exposure prevented?
The most reliable prevention is not having exposure to other dogs during an outbreak. Avoiding group dog situations for several weeks until the risk has passed or vaccination is performed would be recommended. It is important to remember that even with vaccination disease will likely not be 100% prevented. From a hygiene standpoint, Canine Influenza stays alive on surfaces for forty eight hours, clothing for twenty four hours, and hands for twelve hours. Cleaning with standard disinfectants such as dilute bleach kills the virus. Dogs that have been exposed to the virus can shed or pass the virus on for two weeks after exposure. More importantly, dogs will shed the virus most in the days prior to showing clinical signs. This emphasized the importance of limiting exposure to other dogs if Canine Influenza has been identified in a region.

What about vaccination?
While there is a vaccine for Canine Influenza, it requires two injections and protection is not provided for two weeks minimum after the second dose is administered. This means if the first vaccination is given today, a pet would not be protected for at least four weeks. The vaccine does not 100% prevent disease or the spread of disease. Considered a non-core vaccination (meaning only recommended for at risk dogs), Canine Influenza has not been a vaccine routinely given in this area. With this recent outbreak vaccination of dogs frequently exposed to other dogs may be recommended. In a large degree, this will depend on the extent the disease spreads and the duration of the outbreak. Healthy Paws Animal Hospital is in the process of obtaining the vaccination for owners that are interested. There are no major side effects associated with vaccination.