Does your dog love to go to doggy daycare, run at the dog park, or play with his friends in the neighborhood? Was she just adopted from the shelter? Do you love taking your best buddy around town, travel across the country, or compete at sporting events? Well, you may have run into a nasty, hacking cough after one of these excursions. Just like kids at daycare, viral and bacterial respiratory infections spread quickly, often prior to the animal showing any symptoms, so they are hard to prevent. These diseases may be spread through direct contact with infected dogs, airborne particles, and fomites (saliva on our clothing, shared dog bowls, etc). Kennel Cough and Canine Influenza both fall under the broad category of Canine Infectious Respiratory Diseases.
Bordetellosis, commonly called Kennel Cough due to rapid spread through multi-dog environments, is caused by a bacteria known as Bordetella bronchiseptica and it is one of the most common agents for causing canine infectious respiratory disease. It affects dogs and cats and can be passed between them. Bordetellosis is a zoonotic disease, meaning it can be passed to people, though this rare report tends to be in an individual with a weakened immune or respiratory system. When a dog contracts Bordetellosis, the symptoms are often mild and self-limiting with a honking type of cough, gagging, and mild lethargy being the most common symptoms that may last 10-14 days. Some patients may have co-infections with other viruses or bacteria, which results in more severe symptoms including fever, lack of appetite, nasal and ocular discharge, sneezing, severe coughing, trouble breathing and pneumonia. Puppies, unvaccinated dogs, and immunocompromised pets will have a higher risk for pneumonia.
Highly contagious Canine Influenza (dog flu) is increasingly more recognized with outbreaks occurring throughout the United States since 2004 due to H3N8 and H3N2 strains. A mild form can cause symptoms of a cough for 10-30 days, reduced appetite, lethargy, eye and nasal discharge, sneezing, and a mild fever. The severe form will cause a high fever and signs of pneumonia, especially if co-infection with a bacteria has occurred. The fatality rate is less than 10%, so most dogs recover with appropriate care over 2-3 weeks. Zoonotic potential for humans contracting dog flu has not been shown, but transmission of H3N2 to cats may be possible.
For the uncomplicated case of a respiratory infection, an exam by your veterinarian and supportive care at home, along with isolation of the dog from others are typically the mainstays of therapy. Antibiotics, though not always needed, may be prescribed by your veterinarian, and occasionally anti-inflammatories or cough suppressants are used. For those pets with more severe symptoms, bloodwork, chest radiographs, PCR testing or culture swabs may be done to determine the severity of disease and identify the type of infection present. Patients who develop severe sequelae such as pneumonia will require hospitalization for more intensive care.
Prevention is the best medicine in these cases. Vaccination cannot prevent disease 100% of the time, but it can significantly reduce the risk, reduce the severity of symptoms, and reduce shedding of the infection to other animals. Bordetella vaccination is done with either an oral, intranasal, or subcutaneous vaccination. For Canine Influenza vaccination, the bivalent vaccine which protects against both strains is recommended. Your veterinarian can best advise you about the risk for your pet based on their lifestyle and the vaccination protocol.