How to Know If My Dog Has Fleas?

Fleas are those unpleasant jumping insects that can attack our dog. They feed on its blood, and it's their bites that cause itching and even an allergic reaction that can cause considerable skin damage.

In addition, part of the flea's cycle takes place outside the dog, in the environment. This makes them harder to eradicate and easier for them to become a problem, even for us, since they bite humans too. Below, we'll explain how to detect them.

How to Identify a Flea?

The first step is knowing what a flea looks like so we can identify it if we see one. It's a perfectly visible insect without needing any magnification. It has a flattened body to move through fur and well-developed hind legs. They're black or have a brownish-red abdomen. They can be seen on the dog or in the environment.

Normally, if we try to catch them, they'll quickly slip away through the fur or jump. Either way, there will be no doubt it's a flea. Sometimes it's possible to find their larvae, which look like very small white worms, in cracks on the floor, since only adults will be found on the animal.

If we see one of these parasites, there will be no doubt our dog has fleas. Even if it's just one, remember there will be eggs and larvae developing in the environment. See your vet quickly to schedule the most suitable deworming for your dog.

Actual appearance of a flea (enlarged)

What Do Flea Droppings Look Like?

Sometimes we suspect fleas are present but can't manage to see any. In that case, we have another option, which is to look for their traces. Fleas bite the dog to feed on its blood. The bites can be visible as small red marks in areas of the body with less fur, such as the abdomen.

In addition, fleas release their droppings onto the dog. These contain digested blood and look like very small black dots. Like grit. If they're white, they may be eggs. They're found on the dog's body or in its resting spots, since they tend to fall to the ground, being food for the larvae growing in the environment.

Lifting the fur, they can be observed, especially over the back, near the base of the tail. It's also possible to run a comb through the fur to collect them. The way to make sure they're flea droppings is by wetting them. With water they dissolve, and the blood becomes perfectly visible. In that case, there will be no doubt our dog has fleas.

Symptoms of Flea Infestation in a Dog

A dog with fleas can show some clinical signs that should put us on alert. Besides the marks corresponding to the bites, not always visible, the main symptom is itching, which can be more or less intense. A dog may scratch occasionally, just like us. But if it scratches more than normal, we need to be suspicious.

Regular scratching and licking eventually damage the skin, causing wounds of varying severity. In addition, the fur in these areas will also fall out. Without treatment, the skin can become infected. So, regardless of finding fleas or their traces, a dog scratching a lot and showing bald patches and wounds points to the presence of fleas.

Either way, keep in mind that the intensity of the itching or any other sign isn't always related to the number of fleas. The picture varies a lot between individual dogs. Some heavily infested dogs can still seem completely normal, while others, with just a single bite, develop a considerable allergy.

Allergic Dermatitis From Flea Bites

And the allergic reaction angle is very important for figuring out whether our dog has fleas or not. Many dogs suffer from what's known as flea allergy dermatitis, or FAD. It occurs in dogs with hypersensitivity to a component of flea saliva. That's why a single bite is enough to trigger it.

Affected dogs will show very characteristic clinical pictures. These can make us think it's very likely they have fleas. But other conditions could present similarly. That's why it's best to see the vet so they can diagnose and treat it. The signs fleas usually cause in FAD are:

1. Skin lesions from scratching, such as redness, erosions, hair loss, or reddish-brown fur in areas the dog licks frequently.
2. The damage is mainly located in the lumbosacral area, which covers the end of the back and the base of the tail. But it can also be seen in the abdominal and perineal region.
3. This symptomatology is more likely to appear during flea season, though in homes with heating, the period during which they're active extends year-round.
4. If time passes without treatment, the affected skin eventually thickens and darkens.
5. This allergy usually appears between 3-6 years of age. Another detail worth considering when thinking about the presence of fleas in our dog.