Three Symptoms of Infection in Dogs

Written and verified by biochemistry Luz Eduviges Thomas-Romero

Last update: 22 December, 2022

Being the attentive dog owner that you are, you may want to know what the three symptoms of infection are in your animal. This is the right attitude because dogs, just like humans, can become infected throughout their lives.

Generally, there’s no reason for alarm. However, you must be aware of any epidemics lurking around your neighborhood.

Thus, if you know what to look for you’ll be able to detect infection early on before it progresses.

What exactly is an infection?

Infection is the invasion of disease-causing microorganisms in body tissues. However, there are “good” microorganisms that inhabit our bodies and don’t cause infections.

Every creature on the planet has millions of microorganisms living in symbiosis with us. We’re in balance, thanks to them, because they’re essential for many of our vital processes. Scientists refer to this set of “good” microorganisms as a microbiome.

On this note, the causative agents of infectious diseases aren’t normally present in our bodies. As for their nature, they may show up as bacteria, viruses or parasites.

Infectious diseases are contagious and caused by the multiplication of a causative agent. Also, another characteristic of infections is the reaction of host tissues to either the pathogen or the toxins they produce.

Even though an infectious process usually brings a series of symptoms along, there are asymptomatic infections. That is, infections that occur without any visible symptoms, commonly referred to as subclinical infections.

1. Fever

Fever is one of the protective mechanisms that the body puts in place to protect itself. As the temperature rises, the body alerts your immune system to defend itself against infection.

You might have heard that you can tell if your dog has a fever by touching their nose. If it’s hot and dry, then that means fever. However, this isn’t true. In fact, people seldom recognize or detect fever in their dogs.

The only accurate way to know if your dog’s temperature is too high is through rectal temperature reading.

A temperature higher than 103.5º F means a dog has a fever. Do keep in mind they can also be this hot when they’re excited or stressed out. Commonly, the fever comes with lethargy, depression, tremors, loss of appetite, vomiting, cough, or a runny nose.

2. An enlargement of the lymph nodes is one of the symptoms of infection

Lymph nodes are small oval-shaped organs. In addition, they contain immune system cells that attack and kill pathogens, such as viruses.

When a dog has an infection, their lymph nodes become active and send disease-fighting cells so they’ll swell up and hurt. The condition of having swollen lymph nodes is known as lymphadenitis.

Even though there are lymph nodes in many areas of your dog’s body, the easiest ones to detect when they swell up are the submandibular ones. You can find them on each side of the head, near the back of the jaws. Right where these meet the neck. There are also axillary and popliteal nodes, and you can find these at the back of their knees.

3. Secretions

Keep in mind that, in general, the symptoms of bacterial infections depend on their location. Visible infections are often subcutaneous, but they can also affect the surface of the skin. The lesions may appear as wounds and swollen areas.

Swelling may appear as a hard and firm, or soft area. Infected areas may or may not have ulcers on the surface and there may also be a discharge of secretion.

The consistency and color of the secretion vary from watery and pink or red, to thick and yellow or green (what we know as pus). These secretions usually have an unpleasant smell, especially pus.

If the infection takes place inside the animal’s body and out of your sight, then the dog may show other symptoms of illness. For example, there may be lethargy, loss of appetite and weight loss.

If the problem is due to a respiratory tract infection, you may notice signs such as coughing, sneezing, or abnormal breathing. In these situations, secretions may also come out of the nose or mouth or eyes. In addition, your dog may have trouble eating or swallowing.

What if your dog has symptoms of infection

Infections in dogs worry people because they could be fatal if they’re not treated in a timely manner. The seriousness of any type of infection will depend on the type of wound and its location. It also depends on how much time went by before the beginning of treatment, and on the dog’s immune system.

Infection can occur in any part of the body, such as the lungs (pneumonia), the kidneys (pyelonephritis), the brain (encephalitis) and even the skin.

You must contact your veterinarian immediately if you notice that your dog is particularly itchy and has redness, inflammation, and a bad smell. Also if you notice that your dog is scratching, licking or biting their skin excessively. Finally, diarrhea and vomiting might also be symptoms of infection in your dog.