Canine influenza is a highly contagious viral infection that affects dogs and cats. Influenza viruses are able to quickly change and give rise to new strains that can infect different species. Of the two strains identified in the US, both of them can be traced to influenza strains known to infect species other than dogs. At some point, these viruses acquired the ability to infect dogs and be transmitted from dog to dog. Virtually all dogs exposed to canine influenza become infected, with approximately 80% developing clinical signs of disease. The other 20% of infected dogs that do not exhibit clinical signs of the disease can still shed the virus and spread the infection.
Canine influenza is transmitted through droplets or aerosols containing respiratory secretions from coughing, barking, and sneezing. Dogs in close contact with infected dogs in places like kennels, groomers, day care facilities, and shelters are at an increased risk of infection. Canine influenza can be spread indirectly through objects like kennels, food and water bowls, collars, and leashes or people who have been in contact with an infected dog to avoid exposing other dogs to the virus. Due to this, people in contact with an infected dog should wash their hands and clean their clothing to avoid spreading the virus. The virus can stay alive and able to infect on surfaces for up to 48 hours, on clothing for 24 hours, and on hands for 12 hours. It is important to implement cleaning and disinfection procedures to reduce the risk of disease transmission.
The majority of infected dogs exhibit the mild form of canine influenza. The most common clinical sign is a cough that persists for 10-21 days despite treatment with antibiotics and cough suppressants. Affected dogs may have a soft, moist cough, or a dry cough similar to that induced by kennel cough. Nasal and/or ocular discharge, sneezing, lethargy, and anorexia may also be observed. Many dogs developed a purulent nasal discharge and fever. Some dogs are more severely affected and exhibit clinical signs of pneumonia, such as a high-grade fever and increased respiratory rate and effort.
Canine influenza cannot be diagnosed solely by clinical symptoms like coughing, sneezing, and nasal discharge because these signs also present with other canine respiratory illnesses. Tests must be done to properly identify strains of canine influenza virus. Contact Dr. Olsen to set up a test if you think that your dog may be infected.
Treatment for canine influenza is largely supportive. Good nutrition helps dogs mount an effective immune response. Most dogs recover from canine influenza within two to three weeks. Secondary bacterial infections, pneumonia, dehydration, or other health factors may require additional diagnostics and treatments.
While canine influenza is a serious threat, vaccines are available against both strands of canine influenza found in the US. Vaccination can reduce the risk of a dog contracting canine influenza and while it may not all together prevent an infection; it may reduce the severity and duration of illness. As always, feel free to contact Dr. Olsen at 618-656-5868 with any questions or to set up an appointment!