Pneumonia in Dogs - Symptoms, Causes and Treatment

Pneumonia is a general term for an inflammatory lung condition. There are different types of pneumonia in dogs, largely depending on the underlying cause. Most commonly, the pneumonia is due to an infection, although it can also be related to foreign bodies, parasites or even allergens. Pneumonia can also be classified by the different area of the lung which they affect, although they primarily affect the alveoli of the lung, i.e. small air sacs where oxygen is converted into carbon dioxide.

Although the cold does not cause pneumonia, it is true that a dog's immune system can be weakened by low temperatures. Other factors which also weaken the immune system can contribute to canine pneumonia development. For this reason, very young dogs, senior dogs and dogs with immunodeficiency conditions are more likely to develop pneumonia.

Canine pneumonia can is often a secondary condition. It can be the result of untreated or very acute viral infections such as influenza, but it may also develop due to medicated-related lowered immunity. We can better understand the causes of pneumonia in dogs by looking at the different types.

There are many different causes of pneumonia in dogs and we cannot name them all here. However, we can group them into general types. The main types of pneumonia in dogs are the following:

• Viral pneumonia: when a virus causes the inflammatory condition. Various viral agents may result in pneumonia, including the cold and influenza viruses. These often develop when the dog is already immunocompromised.
  
  
• Bacterial pneumonia: this is the most common cause of pneumonia in dogs and it may be the result of various bacteria. These include Bordetella bronchiseptica, Pasteurella multocida, Escherichia coli, Streptococcus zooepidemicus, Klebsiella pneumoniae and Pseudomonas aeruginosa. Kennel cough in dogs is associated with B. bronchiseptica infections, a contagious disease which often affects dogs in groups. This bacterial infection can lead to pneumonia. Learn more with our article on Bordetella in dogs.
  
  
• Mycoplasma pneumonia: although also due to bacteria, this is differentiated because the action of infection is often different. Often a Mycoplasma infection somewhere in the respiratory tract will then develop into a secondary bacterial or viral infection which results in pneumonia. For this reason, it is also known as an atypical pneumonia in dogs.
  
  
• Other pneumonias: these pneumonias are caused by less common infectious agents such as fungi.

There is another category of pneumonia which we will need to detail in the next section below. To learn more about breathing-related disease in canines, take a look at our guide to respiratory infections in dogs.

Although pneumonia in dogs is often related to infectious agents, they are not the only cause of this problem. Irritating substances such as smoke, inhaled food, toxins from plants and others can enter the respiratory system and lead to pneumonia. This can often be exacerbated when the dog has issues swallowing, including megaesophagus, impaired neurological function or swelling in the respiratory tract.

Aspiration pneumonia is a type of lung infection which is caused by material from the mouth or stomach entering the lungs. This can include bacteria, but it also includes foreign objects and other foreign bodies mentioned above. It often occurs in puppies which are being fed artificially, something which happens when the mother is unable to feed her puppies.

When feeding the puppy, it is important we use an appropriate bottle and feed them horizontally. This is unlike how you would feed a human baby. This reduces the risk of food being aspired into the lungs and resulting in secondary infections leading to pneumonia.

Aspiration pneumonia can also be caused by complications from surgery. Anesthetized dogs will have relaxed muscles and it is possible foreign bodies may enter the lungs either during an operation or recovering from one. If a dog has an allergic reaction, the allergen can enter the alveoli and also cause inflammation.

Although the clinical picture will vary depending on the degree of pulmonary involvement, the most characteristic symptoms of pneumonia in dogs are the following:

• Fever
• Apathy
• Anorexia
• Wet cough (indicating the presence of fluid in the lungs)
• Rapid breathing in more severe cases
• Rapid breathing during or after moderate exercise in less severe cases
• Occasionally runny nose

The appearance of any of these symptoms in our dog is reason for veterinary consultation. Your vet may use x-rays, blood tests, or bronchoscopy to make a diagnosis of canine pneumonia.

Learn some other reasons why a dog has a wet nose with green mucus in our related article.

The treatment of pneumonia will depend on the severity of the condition and the underlying cause. As most cases of canine pneumonia are caused by bacteria, antibiotic treatment is required to kill the microorganisms. Since the problem lies deep within the lungs, pneumonia infections can be difficult to treat and require prolonged administration of treatment.

Viral pneumonia is not treatable. In these cases, the dog will need symptom management and supportive treatments to restore their immune system. Doing so will help their bodies to fight the virus. This may include fluid therapy and hospitalization is often required. Cough suppressants are usually not administered as coughing helps to clear the lungs, even if it can be painful for the dog. Mucolytics may be administered to help clear airways.

Recovery will depend on the speed of treatment administration as well as the eradication of the underlying non-respiratory cause. Keep in mind that untreated severe pneumonia can lead to chronic disease or even death of the animal.

Learn about one type of antibiotic which is sometimes used to treat pneumonia with our article on bactrim for dogs.

The following basic guidelines should be followed when treating pneumonia in dogs:

• Provide a warm environment.
• Offer adequate food, prioritizing the dog's preferences, as our goal is to make it eat. We can offer them wet food, homemade food or anything they find appetizing.
• If necessary, administer either oral or parenteral fluid therapy, according to veterinary prescription.
• It is recommended to keep the airways humidified. In dry environments we can use room humidifiers. We can also try to get them to inhale steam, but we need to be careful it is not too hot or forceful. For example, we can put them in the bathroom when we have a hot shower so they inhale the steam.
• Treat the causes that predispose to the onset of pneumonia and/or avoid them as much as possible.

Of course, if the pneumonia doesn't improve or gets worse, you have to go back to the veterinarian.

If your dog is suffering from this condition you may wonder if they have contagious pneumonia. This is a little bit of a misnomer. It is not the pneumonia itself which is contagious, but the the underlying pathogen which causes it. When these are infections agents, they can then be passed on to other dogs. These include bacteria, viruses, fungi or parasites.

We also need to point out that many of these pathogens are species-specific. This means they will only be transmissible to other canines, although there are some pathogens which may cross to other small mammals such as cats. For example, a dog with parvovirus will not be able to pass the disease on to a human as the human will not be a host to the virus.

Practically all of the agents which cause pneumonia in dogs are exclusive to that species. One particular exception is a bacteria which may be involved known as Bordetella bronchiseptica. Although it can be found in humans, it is very a relatively rare occurrence. To date, a direct relationship has not been established that would allow us to confirm that there is contagion between dogs and humans.

Find out more about viral infections in canines with our article on how long does a dog live with parvovirus?

This article is purely informative. AnimalWised does not have the authority to prescribe any veterinary treatment or create a diagnosis. We invite you to take your pet to the veterinarian if they are suffering from any condition or pain.

If you want to read similar articles to Pneumonia in Dogs - Symptoms, Causes and Treatment, we recommend you visit our Breathing diseases category.