Is Upper Respiratory Infection in Dogs Contagious?

Any dog owner should be concerned if their pet develops an upper respiratory infection. The areas that make up the upper respiratory system are the:

  • throat
  • upper bronchial tree
  • larynx
  • pharynx
  • nasal cavities

Upper respiratory infections are actually quite common in dogs. They are normally caused by various bacteria, viruses, and other pathogens. There are rare cases where the upper respiratory infection is caused by parasites, such as mites and lung flukes.

It is extremely common, though, for a dog to develop an upper respiratory infection after leaving an area where dogs are high in density, such as a pet store, dog park or animal shelter. These kinds of places are breeding grounds for the bacteria and pathogens that cause an upper respiratory infection.

Dogs at Risk

Dogs with weak or compromised immune systems are more likely to develop an upper respiratory infection. Dogs that are not up-to-date with their vaccinations, older or elderly dogs, and puppies are also prone to developing an upper respiratory infection. Any dogs that do not have their Bordetella bronchiseptica vaccine shot are at extreme risk for an upper respiratory infection. This risk is increased when the dog is located in an area that is packed with other dogs.

Upper respiratory infection strains that affect dogs can often be passed to other dogs. The strain cannot be passed to animals other than a dog, such as a cat or a human. You should quarantine the dog until it recovers, or you may face a breakout to other dogs.

Bacterial and Viral Infections

The most common bacterial infection, as stated before, is Bordetella bronchiseptica. This strain is what causes tracheobronchitis, which is often referred to as "kennel cough." The problem is that the signs associated with this strain of bacteria is also associated with a dozen other strains of bacteria, such as Klebsiella, Streptococcus, Pseudomonas, and plenty more.

The list is almost twice as long for viral infections that attack the upper respiratory system. The canine distemper virus, canine influenza, and canine herpes can all develop into an upper respiratory infection. The main difference between a bacterial and a viral infection is that a viral infection can lead to a serious upper respiratory disease.


The most common parasite to affect the upper respiratory system is the nasal mite, which is scientifically called Pneumonyssoides caninum. These mites cause the affected dog to sneeze, have a chronic runny nose, develop a cough, and there is a common chance for nose bleeds to occur. These mites can also open up the chance for a bacterial or viral infection to attack, causing an upper respiratory infection.

These mites are spread through direct dog to dog contact. Your pet must come in contact with an infected animal in order to develop it. Lung flukes, on the other hand, do not have any common signs for you to detect if your dog is infected. The only sign that could potentially be noticed is a chronic cough, but not all dogs develop this symptom. Lung flukes cause pulmonary cysts in the lungs, which can lead to an array of other problems.