What Causes Upper Respiratory Infections in Dogs?

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If you’re a dog owner, one of your worst nightmares is probably the thought of your pet becoming sick. Unfortunately, it’s almost inevitably going to happen at some point or another. The good news is that most illnesses are minor and will be shaken off in no time at all. But that doesn’t mean you can afford to take chances. Even health niggles that start out small can sometimes develop into something altogether more serious. Knowing the symptoms to watch out for, and what to do when they occur, is therefore something of a necessary evil.

One of the most common afflictions to strike dogs is upper respiratory infections. To the untrained eye, they can often look like the canine equivalent of the common cold. But unlike a cold, they can lead to all manner of complications and problems that warrant prompt diagnosis and treatment.

Symptoms of Upper Respiratory Infections in Dogs

The symptoms of an upper respiratory infection in dogs can vary depending on the cause of the infection. That said, in most cases, the symptoms will be remarkably similar to what we experience when we have a cold. As dogtime.com notes, the most common indications of an upper respiratory infection include:

Runny, itchy nose
Eye discharge
Sneezing
Dry nose
Coughing (either dry or productive)
Snorting
Wheezing

Other symptoms can be more dramatic, and will typically occur once the infection has taken a strong hold. If you notice any of the following, it’s a sign to get your pet to the vet, pronto:

Fever
Retching
Drooling
Decreased appetite
Weight loss
Dehydration
Lethargy
Foaming at the mouth
Ulcers

Causes of Upper Respiratory Infection in Dogs

As vin.com notes, there are several different bacterial and viral causes of upper respiratory infections in dogs, some of them more serious than others. Of these, some of the most common include:

Bordetella Bronchiseptica – Commonly known as ‘Kennel Cough’, Bordetella bronchiseptica is one of the most common causes of upper respiratory infections in dogs, especially in puppies. Related to Bordetella pertussis (the primary cause of Whooping Cough), Bordetella bronchiseptica is highly contagious and easily spread through coughing, sneezing, and sharing food or water bowls. It can also be carried on clothing. Once it finds a target, it incubates for between 2 to 7 days before revealing itself in a dry, unproductive, honking cough. The cough will usually worsen during activity. Prompt treatment is necessary to avoid further complications: left to develop, secondary bacterial infections such as Strep, E-Coli, and Staph can quickly set in.
Canine Influenza Virus – Although some causes of upper respiratory infections are bacterial in nature, others are viral. Of these, Canine Influenza Virus is one of the most prevalent. As applevalleyvets.com notes, Canine Influenza Virus (or ‘dog flu’, as it’s commonly known) is a fairly recent phenomenon, with the first recorded case happening as recently as 2004. Believed to be a mutation of equine influenza, it can’t be transmitted to humans but is extremely contagious among dogs. With prompt treatment, most dogs will recover without any lasting ill effect. However, cases that aren’t adequality supported can occasionally lead to far more serious complications, including pneumonia, which can sometimes prove fatal. As the wateringbowl.com notes, most cases of canine influenza present with a loud, hacking cough. The cough will usually become worse during exercise and can last for up to a month. In mild cases, a dog may seem slightly lethargic, but will otherwise appear healthy. More severe cases are typically accompanied with a high fever, decreased appetite, a lack of energy, and labored breathing; rapid treatment is recommended in these cases, as the additional symptoms may suggest the dog has developed a secondary infection.
Pneumonyssoides Caninum – Parasites can get up to all sorts of mischief, including triggering a nasty bout of upper respiratory infection. The most common cause of parasitic infection in dogs is the pneumonyssoides caninum (or canine nasal mite, as it’s more commonly known). Another parasite which’s known to cause upper respiratory infection symptoms is the Lung fluke. Thankfully, they’re only transmitted by eating crayfish so the chances of your dog becoming infected are mercifully slim.

How to Prevent Upper Respiratory Infections in Dogs

An ounce of prevention is worth a pound of cure. Although you can’t always protect your dog from illness, there are certain steps you can take to minimize their risk. Vaccinations are your number one safeguard against disease. To prevent kennel cough (one of the most common causes of upper respiratory infections in young dogs), puppies should receive the Intranasal vaccine at four to five weeks old. As well as protecting against kennel cough, the vaccine can also help ward of other causes of infection by creating antibodies that stop viruses and bacteria making themselves at home in the respiratory tract. You might also want to consider an elective vaccination such as the Nobivac Canine Flu H3N8 to protect your dog against canine influenza virus.

How to Treat Upper Respiratory Infection in Dogs

Providing the dog is otherwise fit and healthy, most canine upper respiratory infections will resolve themselves after a few days. That said, you can never be certain that a secondary infection won’t set in. Given that the secondary infection can often by more serious than the primary cause of your dog’s symptoms, it’s always best to seek prompt medical assistance as soon as possible. As there can be many different explanations for a cough or a nasal discharge, your vet will usually recommend blood work and possibly x-rays to rule out any non-infectious causes or more severe respiratory diseases. If the diagnosis is mild, it’s likely the dog will be prescribed antibiotics as a precaution against secondary bacterial infections. If necessary, an expectorant may be recommended to help a cough become more productive. If the dog is suffering as a result of a persistent or particularly severe cough, a cough suppressant may be prescribed to provide some relief. In most cases, the dog will be treated as an outpatient; hospitalization is generally only required in severe cases that warrant oxygen therapy, intravenous fluid therapy and antibiotics, or other forms of intensive treatment. With prompt treatment and proper support, most dogs will recover without any lasting effects.